debug: track expression parse time

clean up all warnings by using new Environment

.github/workflows/liquid.yml

@@ -1,39 +1,36 @@
 name: Liquid
 on: [push, pull_request]
+
+env:
+  BUNDLE_JOBS: 4
+  BUNDLE_RETRY: 3
+
 jobs:
   test:
     runs-on: ubuntu-latest
     strategy:
       matrix:
         entry:
-          - { ruby: 2.7, allowed-failure: false } # minimum supported
-          - { ruby: 3.1, allowed-failure: false } # latest
-          - { ruby: ruby-head, allowed-failure: true }
-    name: test (${{ matrix.entry.ruby }})
+          - { ruby: 3.0, allowed-failure: false } # minimum supported
+          - { ruby: 3.2, allowed-failure: false }
+          - { ruby: 3.3, allowed-failure: false } # latest
+          - { ruby: ruby-head, allowed-failure: false }
+    name: Test Ruby ${{ matrix.entry.ruby }}
     steps:
       - uses: actions/checkout@v3
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.entry.ruby }}
-      - uses: actions/cache@v1
-        with:
-          path: vendor/bundle
-          key: ${{ runner.os }}-gems-${{ hashFiles('Gemfile') }}
-          restore-keys: ${{ runner.os }}-gems-
-      - run: bundle install --jobs=3 --retry=3 --path=vendor/bundle
+          bundler-cache: true
+          bundler: latest
       - run: bundle exec rake
         continue-on-error: ${{ matrix.entry.allowed-failure }}
+
   memory_profile:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 2.7
-      - uses: actions/cache@v1
-        with:
-          path: vendor/bundle
-          key: ${{ runner.os }}-gems-${{ hashFiles('Gemfile') }}
-          restore-keys: ${{ runner.os }}-gems-
-      - run: bundle install --jobs=3 --retry=3 --path=vendor/bundle
+          bundler-cache: true
       - run: bundle exec rake memory_profile:run

.gitignore

@@ -4,7 +4,6 @@
 pkg
 *.rbc
 .rvmrc
-.ruby-version
-Gemfile.lock
 .bundle
 .byebug_history
+Gemfile.lock

.rubocop.yml

@@ -10,8 +10,8 @@ Performance:
   Enabled: true
 
 AllCops:
-  TargetRubyVersion: 2.7
   NewCops: disable
+  SuggestExtensions: false
   Exclude:
     - 'vendor/bundle/**/*'
 
@@ -19,6 +19,10 @@ Naming/MethodName:
   Exclude:
     - 'example/server/liquid_servlet.rb'
 
-# Backport https://github.com/Shopify/ruby-style-guide/pull/258
-Layout/BeginEndAlignment:
-  Enabled: true
+Style/ClassMethodsDefinitions:
+  Enabled: false
+
+# liquid filter calls were being mistaken to be calls on arrays
+Style/ConcatArrayLiterals:
+  Exclude:
+    - 'test/integration/standard_filter_test.rb'

.ruby-version

@@ -0,0 +1 @@
+3.3.4

Gemfile

@@ -7,6 +7,8 @@ end
 
 gemspec
 
+gem "base64"
+
 group :benchmark, :test do
   gem 'benchmark-ips'
   gem 'memory_profiler'
@@ -18,10 +20,11 @@ group :benchmark, :test do
 end
 
 group :test do
-  gem 'rubocop-shopify', '~> 2.7.0', require: false
+  gem 'rubocop', '~> 1.61.0'
+  gem 'rubocop-shopify', '~> 2.12.0', require: false
   gem 'rubocop-performance', require: false
 
   platform :mri, :truffleruby do
-    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'master'
+    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'main'
   end
 end

History.md

@@ -1,5 +1,9 @@
 # Liquid Change Log
 
+## 5.5.0 2024-03-21
+
+Please reference the GitHub release for more information.
+
 ## 5.4.0 2022-07-29
 
 ### Breaking Changes

README.md

@@ -1,11 +1,11 @@
-[![Build Status](https://api.travis-ci.org/Shopify/liquid.svg?branch=master)](http://travis-ci.org/Shopify/liquid)
+[![Build status](https://github.com/Shopify/liquid/actions/workflows/liquid.yml/badge.svg)](https://github.com/Shopify/liquid/actions/workflows/liquid.yml)
 [![Inline docs](http://inch-ci.org/github/Shopify/liquid.svg?branch=master)](http://inch-ci.org/github/Shopify/liquid)
 
 # Liquid template engine
 
 * [Contributing guidelines](CONTRIBUTING.md)
 * [Version history](History.md)
-* [Liquid documentation from Shopify](https://shopify.dev/api/liquid)
+* [Liquid documentation from Shopify](https://shopify.dev/docs/api/liquid)
 * [Liquid Wiki at GitHub](https://github.com/Shopify/liquid/wiki)
 * [Website](http://liquidmarkup.org/)
 
@@ -52,6 +52,47 @@ For standard use you can just pass it the content of a file and call render with
 @template.render('name' => 'tobi')                # => "hi tobi"
 ```
 
+### Concept of Environments
+
+In Liquid, a "Environment" is a scoped environment that encapsulates custom tags, filters, and other configurations. This allows you to define and isolate different sets of functionality for different contexts, avoiding global overrides that can lead to conflicts and unexpected behavior.
+
+By using environments, you can:
+
+1. **Encapsulate Logic**: Keep the logic for different parts of your application separate.
+2. **Avoid Conflicts**: Prevent custom tags and filters from clashing with each other.
+3. **Improve Maintainability**: Make it easier to manage and understand the scope of customizations.
+4. **Enhance Security**: Limit the availability of certain tags and filters to specific contexts.
+
+We encourage the use of Environments over globally overriding things because it promotes better software design principles such as modularity, encapsulation, and separation of concerns.
+
+Here's an example of how you can define and use Environments in Liquid:
+
+```ruby
+user_environment = Liquid::Environment.build do |environment|
+  environment.register_tag("renderobj", RenderObjTag)
+end
+
+Liquid::Template.parse(<<~LIQUID, environment: user_environment)
+  {% renderobj src: "path/to/model.obj" %}
+LIQUID
+```
+
+In this example, `RenderObjTag` is a custom tag that is only available within the `user_environment`.
+
+Similarly, you can define another environment for a different context, such as email templates:
+
+```ruby
+email_environment = Liquid::Environment.build do |environment|
+  environment.register_tag("unsubscribe_footer", UnsubscribeFooter)
+end
+
+Liquid::Template.parse(<<~LIQUID, environment: email_environment)
+  {% unsubscribe_footer %}
+LIQUID
+```
+
+By using Environments, you ensure that custom tags and filters are only available in the contexts where they are needed, making your Liquid templates more robust and easier to manage.
+
 ### Error Modes
 
 Setting the error mode of Liquid lets you specify how strictly you want your templates to be interpreted.
@@ -62,9 +103,10 @@ Liquid also comes with a stricter parser that can be used when editing templates
 when templates are invalid. You can enable this new parser like this:
 
 ```ruby
-Liquid::Template.error_mode = :strict # Raises a SyntaxError when invalid syntax is used
-Liquid::Template.error_mode = :warn # Adds strict errors to template.errors but continues as normal
-Liquid::Template.error_mode = :lax # The default mode, accepts almost anything.
+Liquid::Environment.default.error_mode = :strict
+Liquid::Environment.default.error_mode = :strict # Raises a SyntaxError when invalid syntax is used
+Liquid::Environment.default.error_mode = :warn # Adds strict errors to template.errors but continues as normal
+Liquid::Environment.default.error_mode = :lax # The default mode, accepts almost anything.
 ```
 
 If you want to set the error mode only on specific templates you can pass `:error_mode` as an option to `parse`:
@@ -111,4 +153,4 @@ template.render!({ 'x' => 1}, { strict_variables: true })
 
 To help track usages of a feature or code path in production, we have released opt-in usage tracking. To enable this, we provide an empty `Liquid:: Usage.increment` method which you can customize to your needs. The feature is well suited to https://github.com/Shopify/statsd-instrument. However, the choice of implementation is up to you.
 
-Once you have enabled usage tracking, we recommend reporting any events through Github Issues that your system may be logging. It is highly likely this event has been added to consider deprecating or improving code specific to this event, so please raise any concerns.
+Once you have enabled usage tracking, we recommend reporting any events through Github Issues that your system may be logging. It is highly likely this event has been added to consider deprecating or improving code specific to this event, so please raise any concerns.

Rakefile

@@ -5,7 +5,7 @@ require 'rake/testtask'
 $LOAD_PATH.unshift(File.expand_path("../lib", __FILE__))
 require "liquid/version"
 
-task(default: [:test, "test:migrator_integration", :rubocop])
+task(default: [:test, :rubocop])
 
 desc('run test suite with default parser')
 Rake::TestTask.new(:base_test) do |t|
@@ -33,23 +33,6 @@ task :rubocop do
   end
 end
 
-namespace :test do
-  task :migrator_integration do
-    ENV['LIQUID_MIGRATOR'] = '1'
-    original_parse_mode = ENV['LIQUID_PARSER_MODE']
-    begin
-      Rake::Task['integration_test'].reenable
-      ["lax", "strict"].each do |parse_mode|
-        ENV['LIQUID_PARSER_MODE'] = parse_mode
-        Rake::Task['integration_test'].invoke
-        Rake::Task['integration_test'].reenable
-      end
-    ensure
-      ENV['LIQUID_PARSER_MODE'] = original_parse_mode
-    end
-  end
-end
-
 desc('runs test suite with both strict and lax parsers')
 task :test do
   ENV['LIQUID_PARSER_MODE'] = 'lax'
@@ -98,6 +81,14 @@ namespace :benchmark do
   task :strict do
     ruby "./performance/benchmark.rb strict"
   end
+
+  desc "Run unit benchmarks"
+  task :unit do
+    Dir["./performance/unit/*_benchmark.rb"].each do |file|
+      puts "🧪 Running #{file}"
+      ruby file
+    end
+  end
 end
 
 namespace :profile do

example/server/example_servlet.rb

@@ -30,14 +30,18 @@ class Servlet < LiquidServlet
   private
 
   def products_list
-    [{ 'name' => 'Arbor Draft', 'price' => 39900, 'description' => 'the *arbor draft* is a excellent product' },
-     { 'name' => 'Arbor Element', 'price' => 40000, 'description' => 'the *arbor element* rocks for freestyling' },
-     { 'name' => 'Arbor Diamond', 'price' => 59900, 'description' => 'the *arbor diamond* is a made up product because im obsessed with arbor and have no creativity' }]
+    [
+      { 'name' => 'Arbor Draft', 'price' => 39900, 'description' => 'the *arbor draft* is a excellent product' },
+      { 'name' => 'Arbor Element', 'price' => 40000, 'description' => 'the *arbor element* rocks for freestyling' },
+      { 'name' => 'Arbor Diamond', 'price' => 59900, 'description' => 'the *arbor diamond* is a made up product because im obsessed with arbor and have no creativity' }
+    ]
   end
 
   def more_products_list
-    [{ 'name' => 'Arbor Catalyst', 'price' => 39900, 'description' => 'the *arbor catalyst* is an advanced drop-through for freestyle and flatground performance and versatility' },
-     { 'name' => 'Arbor Fish', 'price' => 40000, 'description' => 'the *arbor fish* is a compact pin that features an extended wheelbase and time-honored teardrop shape' }]
+    [
+      { 'name' => 'Arbor Catalyst', 'price' => 39900, 'description' => 'the *arbor catalyst* is an advanced drop-through for freestyle and flatground performance and versatility' },
+      { 'name' => 'Arbor Fish', 'price' => 40000, 'description' => 'the *arbor fish* is a compact pin that features an extended wheelbase and time-honored teardrop shape' }
+    ]
   end
 
   def description

lib/liquid.rb

@@ -41,16 +41,23 @@ module Liquid
   AnyStartingTag              = /#{TagStart}|#{VariableStart}/o
   PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/om
   TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/om
-  VariableParser              = /\[[^\]]+\]|#{VariableSegment}+\??/o
+  VariableParser              = /\[(?>[^\[\]]+|\g<0>)*\]|#{VariableSegment}+\??/o
 
   RAISE_EXCEPTION_LAMBDA = ->(_e) { raise }
-
-  singleton_class.send(:attr_accessor, :cache_classes)
-  self.cache_classes = true
 end
 
 require "liquid/version"
+require "liquid/deprecations"
+require "liquid/const"
+require 'liquid/standardfilters'
+require 'liquid/file_system'
+require 'liquid/parser_switching'
+require 'liquid/tag'
+require 'liquid/block'
 require 'liquid/parse_tree_visitor'
+require 'liquid/interrupts'
+require 'liquid/tags'
+require "liquid/environment"
 require 'liquid/lexer'
 require 'liquid/parser'
 require 'liquid/i18n'
@@ -61,32 +68,21 @@ require 'liquid/extensions'
 require 'liquid/errors'
 require 'liquid/interrupts'
 require 'liquid/strainer_template'
-require 'liquid/strainer_factory'
 require 'liquid/expression'
 require 'liquid/context'
-require 'liquid/parser_switching'
 require 'liquid/tag'
-require 'liquid/tag/disabler'
-require 'liquid/tag/disableable'
-require 'liquid/parse_context'
-require 'liquid/block'
 require 'liquid/block_body'
 require 'liquid/document'
 require 'liquid/variable'
 require 'liquid/variable_lookup'
 require 'liquid/range_lookup'
-require 'liquid/file_system'
 require 'liquid/resource_limits'
 require 'liquid/template'
-require 'liquid/standardfilters'
 require 'liquid/condition'
 require 'liquid/utils'
 require 'liquid/tokenizer'
+require 'liquid/parse_context'
 require 'liquid/partial_cache'
 require 'liquid/usage'
 require 'liquid/registers'
 require 'liquid/template_factory'
-
-# Load all the tags of the standard library
-#
-Dir["#{__dir__}/liquid/tags/*.rb"].each { |f| require f }

lib/liquid/block.rb

@@ -36,13 +36,17 @@ module Liquid
     # @api private
     def self.raise_unknown_tag(tag, block_name, block_delimiter, parse_context)
       if tag == 'else'
-        raise SyntaxError, parse_context.locale.t("errors.syntax.unexpected_else",
-          block_name: block_name)
+        raise SyntaxError, parse_context.locale.t(
+          "errors.syntax.unexpected_else",
+          block_name: block_name,
+        )
       elsif tag.start_with?('end')
-        raise SyntaxError, parse_context.locale.t("errors.syntax.invalid_delimiter",
+        raise SyntaxError, parse_context.locale.t(
+          "errors.syntax.invalid_delimiter",
           tag: tag,
           block_name: block_name,
-          block_delimiter: block_delimiter)
+          block_delimiter: block_delimiter,
+        )
       else
         raise SyntaxError, parse_context.locale.t("errors.syntax.unknown_tag", tag: tag)
       end
@@ -60,21 +64,6 @@ module Liquid
       @block_delimiter ||= "end#{block_name}"
     end
 
-    def self.migrate_body(start_tag_name, tokenizer, parse_context)
-      new_body, unknown_tag = BlockBody.migrate(tokenizer, parse_context)
-
-      raise SyntaxError unless unknown_tag
-
-      block_delimiter = "end#{start_tag_name}"
-      if unknown_tag.tag_name == block_delimiter
-        new_body << unknown_tag.replaced_markup("") # markup was ignored on end tags
-        return [new_body, nil]
-      end
-
-      # handle the delimiter tag in the caller
-      [new_body, unknown_tag]
-    end
-
     private
 
     # @api public

lib/liquid/block_body.rb

@@ -6,6 +6,7 @@ module Liquid
   class BlockBody
     LiquidTagToken      = /\A\s*(#{TagName})\s*(.*?)\z/o
     FullToken           = /\A#{TagStart}#{WhitespaceControl}?(\s*)(#{TagName})(\s*)(.*?)#{WhitespaceControl}?#{TagEnd}\z/om
+    FullTokenPossiblyInvalid = /\A(.*)#{TagStart}#{WhitespaceControl}?\s*(\w+)\s*(.*)?#{WhitespaceControl}?#{TagEnd}\z/om
     ContentOfVariable   = /\A#{VariableStart}#{WhitespaceControl}?(.*?)#{WhitespaceControl}?#{VariableEnd}\z/om
     WhitespaceOrNothing = /\A\s*\z/
     TAGSTART            = "{%"
@@ -30,16 +31,6 @@ module Liquid
       end
     end
 
-    def self.migrate(tokenizer, parse_context, &block)
-      parse_context.line_number = tokenizer.line_number
-
-      if tokenizer.for_liquid_tag
-        migrate_for_liquid_tag(tokenizer, parse_context, &block)
-      else
-        migrate_for_document(tokenizer, parse_context, &block)
-      end
-    end
-
     def freeze
       @nodelist.freeze
       super
@@ -55,7 +46,13 @@ module Liquid
           end
           tag_name = Regexp.last_match(1)
           markup   = Regexp.last_match(2)
-          unless (tag = registered_tags[tag_name])
+
+          if tag_name == 'liquid'
+            parse_context.line_number -= 1
+            next parse_liquid_tag(markup, parse_context)
+          end
+
+          unless (tag = parse_context.environment.tag_for_name(tag_name))
             # end parsing if we reach an unknown tag and let the caller decide
             # determine how to proceed
             return yield tag_name, markup
@@ -70,57 +67,6 @@ module Liquid
       yield nil, nil
     end
 
-    class UnknownTagMigrator
-      attr_reader :tag_name, :markup
-
-      def initialize(match:, markup_capture_number:, tag_name:, markup:)
-        @match = match
-        @tag_name = tag_name
-        @markup = markup
-        @markup_capture_number = markup_capture_number
-      end
-
-      def original_tag_string
-        @match[0]
-      end
-
-      def replaced_markup(new_markup)
-        Utils.match_capture_replace(@match, @markup_capture_number, new_markup)
-      end
-    end
-
-    private_class_method def self.migrate_for_liquid_tag(tokenizer, parse_context)
-      result = +""
-      while (token = tokenizer.shift)
-        token += "\n" if tokenizer.more?
-        if token.empty? || token.match?(WhitespaceOrNothing)
-          result << token
-        else
-          # modified version of LiquidTagToken with following changes:
-          # * TagName is optional, to continue supporting its absence in the comment tag
-          # * trailing spaces is allowed to support the newline appended above and so the tag
-          #   migrate method doesn't have to handle trailing whitespace
-          match = token.match(/\A\s*(#{TagName})?\s*(.*?)\s*\z/o)
-          tag_name = match[1]
-          markup   = match[2]
-          unless (tag = Template.tags[tag_name])
-            # delegate handling of unknown tags to the caller, where a block tag may treat
-            # it as an end tag or body delimiter.
-            unknown_tag = UnknownTagMigrator.new(
-              match: match, markup_capture_number: 2, tag_name: tag_name, markup: markup
-            )
-            return [result, unknown_tag]
-          end
-          new_markup, new_tag_body = tag.migrate(tag_name, markup, tokenizer, parse_context)
-          result << Utils.match_capture_replace(match, 2, new_markup)
-          result << new_tag_body.to_s
-        end
-        parse_context.line_number = tokenizer.line_number
-      end
-
-      [result, nil]
-    end
-
     # @api private
     def self.unknown_tag_in_liquid_tag(tag, parse_context)
       Block.raise_unknown_tag(tag, 'liquid', '%}', parse_context)
@@ -170,15 +116,6 @@ module Liquid
       end
     end
 
-    private_class_method def self.migrate_liquid_tag(markup, parse_context)
-      liquid_tag_tokenizer = parse_context.new_tokenizer(
-        markup, start_line_number: parse_context.line_number, for_liquid_tag: true
-      )
-      result, unknown_tag = migrate_for_liquid_tag(liquid_tag_tokenizer, parse_context)
-      raise SyntaxError if unknown_tag
-      result
-    end
-
     private def handle_invalid_tag_token(token, parse_context)
       if token.end_with?('%}')
         yield token, token
@@ -210,7 +147,7 @@ module Liquid
             next
           end
 
-          unless (tag = registered_tags[tag_name])
+          unless (tag = parse_context.environment.tag_for_name(tag_name))
             # end parsing if we reach an unknown tag and let the caller decide
             # determine how to proceed
             return yield tag_name, markup
@@ -236,58 +173,6 @@ module Liquid
       yield nil, nil
     end
 
-    private_class_method def self.migrate_for_document(tokenizer, parse_context, &block)
-      result = +""
-      while (token = tokenizer.shift)
-        next if token.empty?
-
-        case
-        when token.start_with?(TAGSTART)
-          raise SyntaxError unless token.end_with?('%}')
-          # modified FullToken regex with optional tag name, to allow its absence in a comment tag
-          match = token.match(/\A#{TagStart}#{WhitespaceControl}?(\s*)(#{TagName})?(\s*)(.*?)#{WhitespaceControl}?#{TagEnd}\z/om)
-          tag_name = match[2]
-          markup   = match[4]
-
-          if parse_context.line_number
-            # newlines inside the tag should increase the line number,
-            # particularly important for multiline {% liquid %} tags
-            parse_context.line_number += Regexp.last_match(1).count("\n") + Regexp.last_match(3).count("\n")
-          end
-
-          if tag_name == 'liquid'
-            new_markup = Utils.migrate_stripped(markup) do |stripped_markup|
-              migrate_liquid_tag(stripped_markup, parse_context)
-            end
-            result << Utils.match_capture_replace(match, 4, new_markup)
-            next
-          end
-
-          unless (tag = Template.tags[tag_name])
-            # delegate handling of unknown tags to the caller, where a block tag may treat
-            # it as an end tag or body delimiter.
-            unknown_tag = UnknownTagMigrator.new(
-              match: match, markup_capture_number: 4, tag_name: tag_name, markup: markup
-            )
-            return [result, unknown_tag]
-          end
-          new_tag_body = nil
-          new_markup = Utils.migrate_stripped(markup) do |stripped_markup|
-            new_stripped_markup, new_tag_body = tag.migrate(tag_name, stripped_markup, tokenizer, parse_context)
-            new_stripped_markup
-          end
-          result << Utils.match_capture_replace(match, 4, new_markup) << new_tag_body.to_s
-        when token.start_with?(VARSTART)
-          result << migrate_variable(token, parse_context)
-        else
-          result << token
-        end
-        parse_context.line_number = tokenizer.line_number
-      end
-
-      [result, nil]
-    end
-
     def whitespace_handler(token, parse_context)
       if token[2] == WhitespaceControl
         previous_token = @nodelist.last
@@ -361,21 +246,17 @@ module Liquid
     end
 
     def create_variable(token, parse_context)
-      if token =~ ContentOfVariable
-        markup = Regexp.last_match(1)
+      if token.end_with?("}}")
+        i = 2
+        i = 3 if token[i] == "-"
+        parse_end = token.length - 3
+        parse_end -= 1 if token[parse_end] == "-"
+        markup_end = parse_end - i + 1
+        markup = markup_end <= 0 ? "" : token.slice(i, markup_end)
+
         return Variable.new(markup, parse_context)
       end
-      BlockBody.raise_missing_variable_terminator(token, parse_context)
-    end
 
-    private_class_method def self.migrate_variable(token, parse_context)
-      match = token.match(ContentOfVariable)
-      if match
-        new_markup = Utils.migrate_stripped(match[1]) do |markup|
-          Variable.migrate(markup, parse_context)
-        end
-        return Utils.match_capture_replace(match, 1, new_markup)
-      end
       BlockBody.raise_missing_variable_terminator(token, parse_context)
     end
 
@@ -388,9 +269,5 @@ module Liquid
     def raise_missing_variable_terminator(token, parse_context)
       BlockBody.raise_missing_variable_terminator(token, parse_context)
     end
-
-    def registered_tags
-      Template.tags
-    end
   end
 end

lib/liquid/condition.rb

@@ -24,6 +24,9 @@ module Liquid
         else
           false
         end
+      rescue Encoding::CompatibilityError
+        # "✅".b.include?("✅") raises Encoding::CompatibilityError despite being materially equal
+        left.b.include?(right.b)
       end,
     }
 
@@ -69,9 +72,9 @@ module Liquid
 
         case condition.child_relation
         when :or
-          break if result
+          break if Liquid::Utils.to_liquid_value(result)
         when :and
-          break unless result
+          break unless Liquid::Utils.to_liquid_value(result)
         else
           break
         end
@@ -159,8 +162,10 @@ module Liquid
     class ParseTreeVisitor < Liquid::ParseTreeVisitor
       def children
         [
-          @node.left, @node.right,
-          @node.child_condition, @node.attachment
+          @node.left,
+          @node.right,
+          @node.child_condition,
+          @node.attachment
         ].compact
       end
     end

lib/liquid/const.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Liquid
+  module Const
+    EMPTY_HASH = {}.freeze
+    EMPTY_ARRAY = [].freeze
+  end
+end

lib/liquid/context.rb

@@ -15,24 +15,25 @@ module Liquid
   #   context['bob']  #=> nil  class Context
   class Context
     attr_reader :scopes, :errors, :registers, :environments, :resource_limits, :static_registers, :static_environments
-    attr_accessor :exception_renderer, :template_name, :partial, :global_filter, :strict_variables, :strict_filters
+    attr_accessor :exception_renderer, :template_name, :partial, :global_filter, :strict_variables, :strict_filters, :environment
 
     # rubocop:disable Metrics/ParameterLists
-    def self.build(environments: {}, outer_scope: {}, registers: {}, rethrow_errors: false, resource_limits: nil, static_environments: {}, &block)
-      new(environments, outer_scope, registers, rethrow_errors, resource_limits, static_environments, &block)
+    def self.build(environment: Environment.default, environments: {}, outer_scope: {}, registers: {}, rethrow_errors: false, resource_limits: nil, static_environments: {}, &block)
+      new(environments, outer_scope, registers, rethrow_errors, resource_limits, static_environments, environment, &block)
     end
 
-    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil, static_environments = {})
+    def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil, static_environments = {}, environment = Environment.default)
+      @environment = environment
       @environments = [environments]
       @environments.flatten!
 
       @static_environments = [static_environments].flatten(1).freeze
-      @scopes              = [(outer_scope || {})]
+      @scopes              = [outer_scope || {}]
       @registers           = registers.is_a?(Registers) ? registers : Registers.new(registers)
       @errors              = []
       @partial             = false
       @strict_variables    = false
-      @resource_limits     = resource_limits || ResourceLimits.new(Template.default_resource_limits)
+      @resource_limits     = resource_limits || ResourceLimits.new(environment.default_resource_limits)
       @base_scope_depth    = 0
       @interrupts          = []
       @filters             = []
@@ -40,10 +41,10 @@ module Liquid
       @disabled_tags       = {}
 
       @registers.static[:cached_partials] ||= {}
-      @registers.static[:file_system] ||= Liquid::Template.file_system
+      @registers.static[:file_system] ||= environment.file_system
       @registers.static[:template_factory] ||= Liquid::TemplateFactory.new
 
-      self.exception_renderer = Template.default_exception_renderer
+      self.exception_renderer = environment.exception_renderer
       if rethrow_errors
         self.exception_renderer = Liquid::RAISE_EXCEPTION_LAMBDA
       end
@@ -60,7 +61,7 @@ module Liquid
     end
 
     def strainer
-      @strainer ||= StrainerFactory.create(self, @filters)
+      @strainer ||= @environment.create_strainer(self, @filters)
     end
 
     # Adds filters to this context.
@@ -142,9 +143,10 @@ module Liquid
       check_overflow
 
       self.class.build(
+        environment: @environment,
         resource_limits: resource_limits,
         static_environments: static_environments,
-        registers: Registers.new(registers)
+        registers: Registers.new(registers),
       ).tap do |subcontext|
         subcontext.base_scope_depth   = base_scope_depth + 1
         subcontext.exception_renderer = exception_renderer
@@ -174,7 +176,12 @@ module Liquid
     # Example:
     #   products == empty #=> products.empty?
     def [](expression)
-      evaluate(Expression.parse(expression))
+      start = Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond)
+      expression_parse_result = Expression.parse(expression)
+      duration = Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond) - start
+      registers.static[:expression_parse_duration] ||= 0
+      registers.static[:expression_parse_duration] += duration
+      evaluate(expression_parse_result)
     end
 
     def key?(key)
@@ -197,10 +204,14 @@ module Liquid
         try_variable_find_in_environments(key, raise_on_not_found: raise_on_not_found)
       end
 
-      variable         = variable.to_liquid
+      # update variable's context before invoking #to_liquid
       variable.context = self if variable.respond_to?(:context=)
 
-      variable
+      liquid_variable = variable.to_liquid
+
+      liquid_variable.context = self if variable != liquid_variable && liquid_variable.respond_to?(:context=)
+
+      liquid_variable
     end
 
     def lookup_and_evaluate(obj, key, raise_on_not_found: true)

lib/liquid/deprecations.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "set"
+
+module Liquid
+  class Deprecations
+    class << self
+      attr_accessor :warned
+
+      Deprecations.warned = Set.new
+
+      def warn(name, alternative)
+        return if warned.include?(name)
+
+        warned << name
+
+        caller_location = caller_locations(2, 1).first
+        Warning.warn("[DEPRECATION] #{name} is deprecated. Use #{alternative} instead. Called from #{caller_location}\n")
+      end
+    end
+  end
+end

lib/liquid/document.rb

@@ -28,16 +28,6 @@ module Liquid
       raise
     end
 
-    def self.migrate(tokenizer, parse_context)
-      new_body, unknown_tag = BlockBody.migrate(tokenizer, parse_context)
-      raise SyntaxError if unknown_tag
-
-      new_body
-    rescue SyntaxError => e
-      e.line_number ||= parse_context.line_number
-      raise
-    end
-
     def unknown_tag(tag, _markup, _tokenizer)
       case tag
       when 'else', 'end'

lib/liquid/drop.rb

@@ -25,6 +25,10 @@ module Liquid
   class Drop
     attr_writer :context
 
+    def initialize
+      @context = nil
+    end
+
     # Catch all for the method
     def liquid_method_missing(method)
       return nil unless @context&.strict_variables

lib/liquid/environment.rb

@@ -0,0 +1,159 @@
+# frozen_string_literal: true
+
+module Liquid
+  # The Environment is the container for all configuration options of Liquid, such as
+  # the registered tags, filters, and the default error mode.
+  class Environment
+    # The default error mode for all templates. This can be overridden on a
+    # per-template basis.
+    attr_accessor :error_mode
+
+    # The tags that are available to use in the template.
+    attr_accessor :tags
+
+    # The strainer template which is used to store filters that are available to
+    # use in templates.
+    attr_accessor :strainer_template
+
+    # The exception renderer that is used to render exceptions that are raised
+    # when rendering a template
+    attr_accessor :exception_renderer
+
+    # The default file system that is used to load templates from.
+    attr_accessor :file_system
+
+    # The default resource limits that are used to limit the resources that a
+    # template can consume.
+    attr_accessor :default_resource_limits
+
+    class << self
+      # Creates a new environment instance.
+      #
+      # @param tags [Hash] The tags that are available to use in
+      #  the template.
+      # @param file_system The default file system that is used
+      #  to load templates from.
+      # @param error_mode [Symbol] The default error mode for all templates
+      #  (either :strict, :warn, or :lax).
+      # @param exception_renderer [Proc] The exception renderer that is used to
+      #   render exceptions.
+      # @yieldparam environment [Environment] The environment instance that is being built.
+      # @return [Environment] The new environment instance.
+      def build(tags: nil, file_system: nil, error_mode: nil, exception_renderer: nil)
+        ret = new
+        ret.tags = tags if tags
+        ret.file_system = file_system if file_system
+        ret.error_mode = error_mode if error_mode
+        ret.exception_renderer = exception_renderer if exception_renderer
+        yield ret if block_given?
+        ret.freeze
+      end
+
+      # Returns the default environment instance.
+      #
+      # @return [Environment] The default environment instance.
+      def default
+        @default ||= new
+      end
+
+      # Sets the default environment instance for the duration of the block
+      #
+      # @param environment [Environment] The environment instance to use as the default for the
+      #   duration of the block.
+      # @yield
+      # @return [Object] The return value of the block.
+      def dangerously_override(environment)
+        original_default = @default
+        @default = environment
+        yield
+      ensure
+        @default = original_default
+      end
+    end
+
+    # Initializes a new environment instance.
+    # @api private
+    def initialize
+      @tags = Tags::STANDARD_TAGS.dup
+      @error_mode = :lax
+      @strainer_template = Class.new(StrainerTemplate).tap do |klass|
+        klass.add_filter(StandardFilters)
+      end
+      @exception_renderer = ->(exception) { exception }
+      @file_system = BlankFileSystem.new
+      @default_resource_limits = Const::EMPTY_HASH
+      @strainer_template_class_cache = {}
+    end
+
+    # Registers a new tag with the environment.
+    #
+    # @param name [String] The name of the tag.
+    # @param klass [Liquid::Tag] The class that implements the tag.
+    # @return [void]
+    def register_tag(name, klass)
+      @tags[name] = klass
+    end
+
+    # Registers a new filter with the environment.
+    #
+    # @param filter [Module] The module that contains the filter methods.
+    # @return [void]
+    def register_filter(filter)
+      @strainer_template_class_cache.clear
+      @strainer_template.add_filter(filter)
+    end
+
+    # Registers multiple filters with this environment.
+    #
+    # @param filters [Array<Module>] The modules that contain the filter methods.
+    # @return [self]
+    def register_filters(filters)
+      @strainer_template_class_cache.clear
+      filters.each { |f| @strainer_template.add_filter(f) }
+      self
+    end
+
+    # Creates a new strainer instance with the given filters, caching the result
+    # for faster lookup.
+    #
+    # @param context [Liquid::Context] The context that the strainer will be
+    #   used in.
+    # @param filters [Array<Module>] The filters that the strainer will have
+    #   access to.
+    # @return [Liquid::Strainer] The new strainer instance.
+    def create_strainer(context, filters = Const::EMPTY_ARRAY)
+      return @strainer_template.new(context) if filters.empty?
+
+      strainer_template = @strainer_template_class_cache[filters] ||= begin
+        klass = Class.new(@strainer_template)
+        filters.each { |f| klass.add_filter(f) }
+        klass
+      end
+
+      strainer_template.new(context)
+    end
+
+    # Returns the names of all the filter methods that are available to use in
+    # the strainer template.
+    #
+    # @return [Array<String>] The names of all the filter methods.
+    def filter_method_names
+      @strainer_template.filter_method_names
+    end
+
+    # Returns the tag class for the given tag name.
+    #
+    # @param name [String] The name of the tag.
+    # @return [Liquid::Tag] The tag class.
+    def tag_for_name(name)
+      @tags[name]
+    end
+
+    def freeze
+      @tags.freeze
+      # TODO: freeze the tags, currently this is not possible because of liquid-c
+      # @strainer_template.freeze
+      super
+    end
+  end
+end

lib/liquid/errors.rb

@@ -40,19 +40,20 @@ module Liquid
     end
   end
 
-  ArgumentError       = Class.new(Error)
-  ContextError        = Class.new(Error)
-  FileSystemError     = Class.new(Error)
-  StandardError       = Class.new(Error)
-  SyntaxError         = Class.new(Error)
-  StackLevelError     = Class.new(Error)
-  MemoryError         = Class.new(Error)
-  ZeroDivisionError   = Class.new(Error)
-  FloatDomainError    = Class.new(Error)
-  UndefinedVariable   = Class.new(Error)
-  UndefinedDropMethod = Class.new(Error)
-  UndefinedFilter     = Class.new(Error)
-  MethodOverrideError = Class.new(Error)
-  DisabledError       = Class.new(Error)
-  InternalError       = Class.new(Error)
+  ArgumentError         = Class.new(Error)
+  ContextError          = Class.new(Error)
+  FileSystemError       = Class.new(Error)
+  StandardError         = Class.new(Error)
+  SyntaxError           = Class.new(Error)
+  StackLevelError       = Class.new(Error)
+  MemoryError           = Class.new(Error)
+  ZeroDivisionError     = Class.new(Error)
+  FloatDomainError      = Class.new(Error)
+  UndefinedVariable     = Class.new(Error)
+  UndefinedDropMethod   = Class.new(Error)
+  UndefinedFilter       = Class.new(Error)
+  MethodOverrideError   = Class.new(Error)
+  DisabledError         = Class.new(Error)
+  InternalError         = Class.new(Error)
+  TemplateEncodingError = Class.new(Error)
 end

lib/liquid/expression.rb

@@ -3,7 +3,10 @@
 module Liquid
   class Expression
     LITERALS = {
-      nil => nil, 'nil' => nil, 'null' => nil, '' => nil,
+      nil => nil,
+      'nil' => nil,
+      'null' => nil,
+      '' => nil,
       'true' => true,
       'false' => false,
       'blank' => '',
@@ -41,36 +44,5 @@ module Liquid
         end
       end
     end
-
-    def self.lax_migrate(markup)
-      Utils.migrate_stripped(markup) do |markup|
-        raise ArgumentError, "unexpected empty expression" if markup.empty?
-
-        if (markup.start_with?('"') && markup.end_with?('"')) ||
-           (markup.start_with?("'") && markup.end_with?("'"))
-          markup
-        else
-          case markup
-          when INTEGERS_REGEX
-            markup
-          when RANGES_REGEX
-            match = Regexp.last_match
-            new_start, new_end = RangeLookup.lax_migrate(match[1], match[2])
-            Utils.match_captures_replace(match, 1 => new_start, 2 => new_end)
-          when FLOATS_REGEX
-            # lax parser allowed multiple periods, but the second period and following characters were ignored
-            new_markup = markup.slice(/\A(-?\d+\.\d*)/)
-            new_markup << "0" if new_markup.end_with?(".")
-            new_markup
-          else
-            if LITERALS.key?(markup)
-              markup
-            else
-              VariableLookup.lax_migrate(markup)
-            end
-          end
-        end
-      end
-    end
   end
 end

lib/liquid/forloop_drop.rb

@@ -5,7 +5,7 @@ module Liquid
   # @liquid_type object
   # @liquid_name forloop
   # @liquid_summary
-  #   Information about a parent [`for` loop](/api/liquid/tags/for).
+  #   Information about a parent [`for` loop](/docs/api/liquid/tags/for).
   class ForloopDrop < Drop
     def initialize(name, length, parentloop)
       @name       = name

lib/liquid/lexer.rb

@@ -1,8 +1,9 @@
 # frozen_string_literal: true
 
 require "strscan"
+
 module Liquid
-  class Lexer
+  class Lexer1
     SPECIALS = {
       '|' => :pipe,
       '.' => :dot,
@@ -58,4 +59,179 @@ module Liquid
       @output << [:end_of_string]
     end
   end
+
+  class Lexer2
+    CLOSE_ROUND = [:close_round, ")"].freeze
+    CLOSE_SQUARE = [:close_square, "]"].freeze
+    COLON = [:colon, ":"].freeze
+    COMMA = [:comma, ","].freeze
+    COMPARISION_NOT_EQUAL = [:comparison, "!="].freeze
+    COMPARISON_CONTAINS = [:comparison, "contains"].freeze
+    COMPARISON_EQUAL = [:comparison, "=="].freeze
+    COMPARISON_GREATER_THAN = [:comparison, ">"].freeze
+    COMPARISON_GREATER_THAN_OR_EQUAL = [:comparison, ">="].freeze
+    COMPARISON_LESS_THAN = [:comparison, "<"].freeze
+    COMPARISON_LESS_THAN_OR_EQUAL = [:comparison, "<="].freeze
+    COMPARISON_NOT_EQUAL_ALT = [:comparison, "<>"].freeze
+    DASH = [:dash, "-"].freeze
+    DOT = [:dot, "."].freeze
+    DOTDOT = [:dotdot, ".."].freeze
+    DOT_ORD = ".".ord
+    DOUBLE_STRING_LITERAL = /"[^\"]*"/
+    EOS = [:end_of_string].freeze
+    IDENTIFIER            = /[a-zA-Z_][\w-]*\??/
+    NUMBER_LITERAL        = /-?\d+(\.\d+)?/
+    OPEN_ROUND = [:open_round, "("].freeze
+    OPEN_SQUARE = [:open_square, "["].freeze
+    PIPE = [:pipe, "|"].freeze
+    QUESTION = [:question, "?"].freeze
+    RUBY_WHITESPACE = [" ", "\t", "\r", "\n", "\f"].freeze
+    SINGLE_STRING_LITERAL = /'[^\']*'/
+    WHITESPACE_OR_NOTHING = /\s*/
+
+    SINGLE_COMPARISON_TOKENS = [].tap do |table|
+      table["<".ord] = COMPARISON_LESS_THAN
+      table[">".ord] = COMPARISON_GREATER_THAN
+    end
+
+    TWO_CHARS_COMPARISON_JUMP_TABLE = [].tap do |table|
+      table["=".ord] = [].tap do |sub_table|
+        sub_table["=".ord] = COMPARISON_EQUAL
+        sub_table.freeze
+      end
+      table["!".ord] = [].tap do |sub_table|
+        sub_table["=".ord] = COMPARISION_NOT_EQUAL
+        sub_table.freeze
+      end
+    end
+
+    COMPARISON_JUMP_TABLE = [].tap do |table|
+      table["<".ord] = [].tap do |sub_table|
+        sub_table["=".ord] = COMPARISON_LESS_THAN_OR_EQUAL
+        sub_table[">".ord] = COMPARISON_NOT_EQUAL_ALT
+        RUBY_WHITESPACE.each { |c| sub_table[c.ord] = COMPARISON_LESS_THAN }
+        sub_table.freeze
+      end
+      table[">".ord] = [].tap do |sub_table|
+        sub_table["=".ord] = COMPARISON_GREATER_THAN_OR_EQUAL
+        RUBY_WHITESPACE.each { |c| sub_table[c.ord] = COMPARISON_GREATER_THAN }
+        sub_table.freeze
+      end
+      table.freeze
+    end
+
+    NEXT_MATCHER_JUMP_TABLE = [].tap do |table|
+      "a".upto("z") do |c|
+        table[c.ord] = [:id, IDENTIFIER].freeze
+        table[c.upcase.ord] = [:id, IDENTIFIER].freeze
+      end
+      table["_".ord] = [:id, IDENTIFIER].freeze
+
+      "0".upto("9") do |c|
+        table[c.ord] = [:number, NUMBER_LITERAL].freeze
+      end
+      table["-".ord] = [:number, NUMBER_LITERAL].freeze
+
+      table["'".ord] = [:string, SINGLE_STRING_LITERAL].freeze
+      table["\"".ord] = [:string, DOUBLE_STRING_LITERAL].freeze
+      table.freeze
+    end
+
+    SPECIAL_TABLE = [].tap do |table|
+      table["|".ord] = PIPE
+      table[".".ord] = DOT
+      table[":".ord] = COLON
+      table[",".ord] = COMMA
+      table["[".ord] = OPEN_SQUARE
+      table["]".ord] = CLOSE_SQUARE
+      table["(".ord] = OPEN_ROUND
+      table[")".ord] = CLOSE_ROUND
+      table["?".ord] = QUESTION
+      table["-".ord] = DASH
+    end
+
+    NUMBER_TABLE = [].tap do |table|
+      "0".upto("9") do |c|
+        table[c.ord] = true
+      end
+      table.freeze
+    end
+
+    def initialize(input)
+      @ss = StringScanner.new(input)
+    end
+
+    # rubocop:disable Metrics/BlockNesting
+    def tokenize
+      @output = []
+
+      until @ss.eos?
+        @ss.skip(WHITESPACE_OR_NOTHING)
+
+        break if @ss.eos?
+
+        start_pos = @ss.pos
+        peeked = @ss.peek_byte
+
+        if (special = SPECIAL_TABLE[peeked])
+          @ss.scan_byte
+          # Special case for ".."
+          if special == DOT && @ss.peek_byte == DOT_ORD
+            @ss.scan_byte
+            @output << DOTDOT
+          elsif special == DASH
+            # Special case for negative numbers
+            if (peeked_byte = @ss.peek_byte) && NUMBER_TABLE[peeked_byte]
+              @ss.pos -= 1
+              @output << [:number, @ss.scan(NUMBER_LITERAL)]
+            else
+              @output << special
+            end
+          else
+            @output << special
+          end
+        elsif (sub_table = TWO_CHARS_COMPARISON_JUMP_TABLE[peeked])
+          @ss.scan_byte
+          if (peeked_byte = @ss.peek_byte) && (found = sub_table[peeked_byte])
+            @output << found
+            @ss.scan_byte
+          else
+            raise_syntax_error(start_pos)
+          end
+        elsif (sub_table = COMPARISON_JUMP_TABLE[peeked])
+          @ss.scan_byte
+          if (peeked_byte = @ss.peek_byte) && (found = sub_table[peeked_byte])
+            @output << found
+            @ss.scan_byte
+          else
+            @output << SINGLE_COMPARISON_TOKENS[peeked]
+          end
+        else
+          type, pattern = NEXT_MATCHER_JUMP_TABLE[peeked]
+
+          if type && (t = @ss.scan(pattern))
+            # Special case for "contains"
+            @output << if type == :id && t == "contains" && @output.last&.first != :dot
+              COMPARISON_CONTAINS
+            else
+              [type, t]
+            end
+          else
+            raise_syntax_error(start_pos)
+          end
+        end
+      end
+      # rubocop:enable Metrics/BlockNesting
+
+      @output << EOS
+    end
+
+    def raise_syntax_error(start_pos)
+      @ss.pos = start_pos
+      # the character could be a UTF-8 character, use getch to get all the bytes
+      raise SyntaxError, "Unexpected character #{@ss.getch}"
+    end
+  end
+
+  Lexer = StringScanner.instance_methods.include?(:scan_byte) ? Lexer2 : Lexer1
 end

lib/liquid/locales/en.yml

@@ -15,6 +15,7 @@
       include: "Error in tag 'include' - Valid syntax: include '[template]' (with|for) [object|collection]"
       inline_comment_invalid: "Syntax error in tag '#' - Each line of comments must be prefixed by the '#' character"
       invalid_delimiter: "'%{tag}' is not a valid delimiter for %{block_name} tags. use %{block_delimiter}"
+      invalid_template_encoding: "Invalid template encoding"
       render: "Syntax error in tag 'render' - Template name must be a quoted string"
       table_row: "Syntax Error in 'table_row loop' - Valid syntax: table_row [item] in [collection] cols=3"
       tag_never_closed: "'%{block_name}' tag was never closed"

lib/liquid/parse_context.rb

@@ -3,12 +3,10 @@
 module Liquid
   class ParseContext
     attr_accessor :locale, :line_number, :trim_whitespace, :depth
-    attr_reader :partial, :warnings, :error_mode
+    attr_reader :partial, :warnings, :error_mode, :environment
 
-    # @api private
-    attr_writer :error_mode
-
-    def initialize(options = {})
+    def initialize(options = Const::EMPTY_HASH)
+      @environment = options.fetch(:environment, Environment.default)
       @template_options = options ? options.dup : {}
 
       @locale   = @template_options[:locale] ||= I18n.new
@@ -38,7 +36,7 @@ module Liquid
       @partial = value
       @options = value ? partial_options : @template_options
 
-      @error_mode = @options[:error_mode] || Template.error_mode
+      @error_mode = @options[:error_mode] || @environment.error_mode
     end
 
     def partial_options

lib/liquid/parse_tree_visitor.rb

@@ -36,7 +36,7 @@ module Liquid
     protected
 
     def children
-      @node.respond_to?(:nodelist) ? Array(@node.nodelist) : []
+      @node.respond_to?(:nodelist) ? Array(@node.nodelist) : Const::EMPTY_ARRAY
     end
   end
 end

lib/liquid/parser.rb

@@ -53,7 +53,7 @@ module Liquid
         str = consume
         str << variable_lookups
       when :open_square
-        str = consume
+        str = consume.dup
         str << expression
         str << consume(:close_square)
         str << variable_lookups

lib/liquid/parser_switching.rb

@@ -2,30 +2,6 @@
 
 module Liquid
   module ParserSwitching
-    module ClassMethods
-      def migrate_with_selected_parser(tag_name, markup, tokenizer, parse_context)
-        case parse_context.error_mode
-        when :strict then strict_migrate(tag_name, markup, tokenizer, parse_context)
-        when :lax    then lax_migrate(tag_name, markup, tokenizer, parse_context)
-        when :warn
-          begin
-            parse_context.error_mode = :strict
-            begin
-              # Use exception side effect to conditionally branch to lax migration
-              parse(tag_name, markup, tokenizer, parse_context)
-            ensure
-              parse_context.error_mode = :warn
-            end
-
-            strict_migrate(tag_name, markup, tokenizer, parse_context)
-          rescue SyntaxError => e
-            parse_context.warnings << e
-            lax_migrate(tag_name, markup, tokenizer, parse_context)
-          end
-        end
-      end
-    end
-
     def strict_parse_with_error_mode_fallback(markup)
       strict_parse_with_error_context(markup)
     rescue SyntaxError => e

lib/liquid/partial_cache.rb

@@ -4,7 +4,8 @@ module Liquid
   class PartialCache
     def self.load(template_name, context:, parse_context:)
       cached_partials = context.registers[:cached_partials]
-      cached = cached_partials[template_name]
+      cache_key = "#{template_name}:#{parse_context.error_mode}"
+      cached = cached_partials[cache_key]
       return cached if cached
 
       file_system = context.registers[:file_system]
@@ -15,8 +16,16 @@ module Liquid
       template_factory = context.registers[:template_factory]
       template = template_factory.for(template_name)
 
-      partial = template.parse(source, parse_context)
-      cached_partials[template_name] = partial
+      begin
+        partial = template.parse(source, parse_context)
+      rescue Liquid::Error => e
+        e.template_name = template&.name || template_name
+        raise e
+      end
+
+      partial.name ||= template_name
+
+      cached_partials[cache_key] = partial
     ensure
       parse_context.partial = false
     end

lib/liquid/range_lookup.rb

@@ -22,37 +22,6 @@ module Liquid
       end
     end
 
-    def self.lax_migrate(start_markup, end_markup)
-      new_start = Expression.lax_migrate(start_markup)
-      new_end = Expression.lax_migrate(end_markup)
-
-      # cast literals
-      start_obj = Expression.parse(new_start)
-      end_obj   = Expression.parse(new_end)
-      if start_obj.respond_to?(:evaluate) || end_obj.respond_to?(:evaluate)
-        new_start = lax_migrate_range_expression(new_start, start_obj)
-        new_end = lax_migrate_range_expression(new_end, end_obj)
-      else
-        new_start = start_obj.to_i.to_s unless start_obj.is_a?(Integer)
-        new_end = end_obj.to_i.to_s unless end_obj.is_a?(Integer)
-      end
-
-      [new_start, new_end]
-    end
-
-    def self.lax_migrate_range_expression(markup, expression)
-      return markup if expression.respond_to?(:evaluate)
-
-      case expression
-      when Integer
-        markup
-      when NilClass, String
-        expression.to_i.to_s
-      else
-        Utils.to_integer(input).to_s
-      end
-    end
-
     attr_reader :start_obj, :end_obj
 
     def initialize(start_obj, end_obj)

lib/liquid/standardfilters.rb

@@ -25,10 +25,23 @@ module Liquid
     STRIP_HTML_BLOCKS       = Regexp.union(
       %r{<script.*?</script>}m,
       /<!--.*?-->/m,
-      %r{<style.*?</style>}m
+      %r{<style.*?</style>}m,
     )
     STRIP_HTML_TAGS = /<.*?>/m
 
+    class << self
+      def try_coerce_encoding(input, encoding:)
+        original_encoding = input.encoding
+        if input.encoding != encoding
+          input.force_encoding(encoding)
+          unless input.valid_encoding?
+            input.force_encoding(original_encoding)
+          end
+        end
+        input
+      end
+    end
+
     # @liquid_public_docs
     # @liquid_type filter
     # @liquid_category array
@@ -69,7 +82,7 @@ module Liquid
     # @liquid_type filter
     # @liquid_category string
     # @liquid_summary
-    #   Capitalizes the first word in a string.
+    #   Capitalizes the first word in a string and downcases the remaining characters.
     # @liquid_syntax string | capitalize
     # @liquid_return [string]
     def capitalize(input)
@@ -150,7 +163,8 @@ module Liquid
     # @liquid_syntax string | base64_decode
     # @liquid_return [string]
     def base64_decode(input)
-      Base64.strict_decode64(input.to_s)
+      input = input.to_s
+      StandardFilters.try_coerce_encoding(Base64.strict_decode64(input), encoding: input.encoding)
     rescue ::ArgumentError
       raise Liquid::ArgumentError, "invalid base64 provided to base64_decode"
     end
@@ -174,7 +188,8 @@ module Liquid
     # @liquid_syntax string | base64_url_safe_decode
     # @liquid_return [string]
     def base64_url_safe_decode(input)
-      Base64.urlsafe_decode64(input.to_s)
+      input = input.to_s
+      StandardFilters.try_coerce_encoding(Base64.urlsafe_decode64(input), encoding: input.encoding)
     rescue ::ArgumentError
       raise Liquid::ArgumentError, "invalid base64 provided to base64_url_safe_decode"
     end
@@ -615,7 +630,7 @@ module Liquid
     # @liquid_description
     #   > Note:
     #   > The `concat` filter won't filter out duplicates. If you want to remove duplicates, then you need to use the
-    #   > [`uniq` filter](/api/liquid/filters/uniq).
+    #   > [`uniq` filter](/docs/api/liquid/filters/uniq).
     # @liquid_syntax array | concat: array
     # @liquid_return [array[untyped]]
     def concat(input, array)
@@ -757,7 +772,7 @@ module Liquid
     # @liquid_type filter
     # @liquid_category math
     # @liquid_summary
-    #   Divides a number by a given number.
+    #   Divides a number by a given number. The `divided_by` filter produces a result of the same type as the divisor. This means if you divide by an integer, the result will be an integer, and if you divide by a float, the result will be a float.
     # @liquid_syntax number | divided_by: number
     # @liquid_return [number]
     def divided_by(input, operand)
@@ -857,18 +872,48 @@ module Liquid
     # @liquid_summary
     #   Sets a default value for any variable whose value is one of the following:
     #
-    #   - [`empty`](/api/liquid/basics#empty)
-    #   - [`false`](/api/liquid/basics#truthy-and-falsy)
-    #   - [`nil`](/api/liquid/basics#nil)
+    #   - [`empty`](/docs/api/liquid/basics#empty)
+    #   - [`false`](/docs/api/liquid/basics#truthy-and-falsy)
+    #   - [`nil`](/docs/api/liquid/basics#nil)
     # @liquid_syntax variable | default: variable
     # @liquid_return [untyped]
-    # @liquid_optional_param allow_false [boolean] Whether to use false values instead of the default.
+    # @liquid_optional_param allow_false: [boolean] Whether to use false values instead of the default.
     def default(input, default_value = '', options = {})
       options = {} unless options.is_a?(Hash)
       false_check = options['allow_false'] ? input.nil? : !Liquid::Utils.to_liquid_value(input)
       false_check || (input.respond_to?(:empty?) && input.empty?) ? default_value : input
     end
 
+    # @liquid_public_docs
+    # @liquid_type filter
+    # @liquid_category array
+    # @liquid_summary
+    #   Returns the sum of all elements in an array.
+    # @liquid_syntax array | sum
+    # @liquid_return [number]
+    def sum(input, property = nil)
+      ary = InputIterator.new(input, context)
+      return 0 if ary.empty?
+
+      values_for_sum = ary.map do |item|
+        if property.nil?
+          item
+        elsif item.respond_to?(:[])
+          item[property]
+        else
+          0
+        end
+      rescue TypeError
+        raise_property_error(property)
+      end
+
+      result = InputIterator.new(values_for_sum, context).sum do |item|
+        Utils.to_number(item)
+      end
+
+      result.is_a?(BigDecimal) ? result.to_f : result
+    end
+
     private
 
     attr_reader :context
@@ -899,6 +944,8 @@ module Liquid
     def nil_safe_casecmp(a, b)
       if !a.nil? && !b.nil?
         a.to_s.casecmp(b.to_s)
+      elsif a.nil? && b.nil?
+        0
       else
         a.nil? ? 1 : -1
       end
@@ -954,6 +1001,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_filter(StandardFilters)
 end

lib/liquid/strainer_factory.rb

@@ -1,41 +0,0 @@
-# frozen_string_literal: true
-
-module Liquid
-  # StrainerFactory is the factory for the filters system.
-  module StrainerFactory
-    extend self
-
-    def add_global_filter(filter)
-      strainer_class_cache.clear
-      GlobalCache.add_filter(filter)
-    end
-
-    def create(context, filters = [])
-      strainer_from_cache(filters).new(context)
-    end
-
-    def global_filter_names
-      GlobalCache.filter_method_names
-    end
-
-    GlobalCache = Class.new(StrainerTemplate)
-
-    private
-
-    def strainer_from_cache(filters)
-      if filters.empty?
-        GlobalCache
-      else
-        strainer_class_cache[filters] ||= begin
-          klass = Class.new(GlobalCache)
-          filters.each { |f| klass.add_filter(f) }
-          klass
-        end
-      end
-    end
-
-    def strainer_class_cache
-      @strainer_class_cache ||= {}
-    end
-  end
-end

lib/liquid/tablerowloop_drop.rb

@@ -5,7 +5,7 @@ module Liquid
   # @liquid_type object
   # @liquid_name tablerowloop
   # @liquid_summary
-  #   Information about a parent [`tablerow` loop](/api/liquid/tags/tablerow).
+  #   Information about a parent [`tablerow` loop](/docs/api/liquid/tags/tablerow).
   class TablerowloopDrop < Drop
     def initialize(length, cols)
       @length = length

lib/liquid/tag.rb

@@ -1,5 +1,8 @@
 # frozen_string_literal: true
 
+require 'liquid/tag/disabler'
+require 'liquid/tag/disableable'
+
 module Liquid
   class Tag
     attr_reader :nodelist, :tag_name, :line_number, :parse_context
@@ -7,8 +10,6 @@ module Liquid
     include ParserSwitching
 
     class << self
-      include ParserSwitching::ClassMethods
-
       def parse(tag_name, markup, tokenizer, parse_context)
         tag = new(tag_name, markup, parse_context)
         tag.parse(tokenizer)
@@ -56,7 +57,8 @@ module Liquid
     # of the `render_to_output_buffer` method will become the default and the `render`
     # method will be removed.
     def render_to_output_buffer(context, output)
-      output << render(context)
+      render_result = render(context)
+      output << render_result if render_result
       output
     end
 

lib/liquid/tags.rb

@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require_relative "tags/table_row"
+require_relative "tags/echo"
+require_relative "tags/if"
+require_relative "tags/break"
+require_relative "tags/inline_comment"
+require_relative "tags/for"
+require_relative "tags/assign"
+require_relative "tags/ifchanged"
+require_relative "tags/case"
+require_relative "tags/include"
+require_relative "tags/continue"
+require_relative "tags/capture"
+require_relative "tags/decrement"
+require_relative "tags/unless"
+require_relative "tags/increment"
+require_relative "tags/comment"
+require_relative "tags/raw"
+require_relative "tags/render"
+require_relative "tags/cycle"
+
+module Liquid
+  module Tags
+    STANDARD_TAGS = {
+      'cycle' => Cycle,
+      'render' => Render,
+      'raw' => Raw,
+      'comment' => Comment,
+      'increment' => Increment,
+      'unless' => Unless,
+      'decrement' => Decrement,
+      'capture' => Capture,
+      'continue' => Continue,
+      'include' => Include,
+      'case' => Case,
+      'ifchanged' => Ifchanged,
+      'assign' => Assign,
+      'for' => For,
+      '#' => InlineComment,
+      'break' => Break,
+      'if' => If,
+      'echo' => Echo,
+      'tablerow' => TableRow,
+    }.freeze
+  end
+end

lib/liquid/tags/assign.rb

@@ -8,7 +8,7 @@ module Liquid
   # @liquid_summary
   #   Creates a new variable.
   # @liquid_description
-  #   You can create variables of any [basic type](/api/liquid/basics#types), [object](/api/liquid/objects), or object property.
+  #   You can create variables of any [basic type](/docs/api/liquid/basics#types), [object](/docs/api/liquid/objects), or object property.
   # @liquid_syntax
   #   {% assign variable_name = value %}
   # @liquid_syntax_keyword variable_name The name of the variable being created.
@@ -21,18 +21,6 @@ module Liquid
       raise Liquid::SyntaxError, parse_context.locale.t('errors.syntax.assign')
     end
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      match = markup.match(Syntax)
-      new_variable_markup = Variable.migrate(match[2], parse_context)
-      new_markup = Utils.match_captures_replace(match, 2 => new_variable_markup)
-
-      # replace scanned over characters with a space to ensure there is a space
-      # to separate the tag name and the variable name
-      new_markup.prepend(" ") if match.begin(0) > 0
-
-      new_markup
-    end
-
     attr_reader :to, :from
 
     def initialize(tag_name, markup, parse_context)
@@ -84,6 +72,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('assign', Assign)
 end

lib/liquid/tags/break.rb

@@ -15,21 +15,15 @@ module Liquid
   # @liquid_category iteration
   # @liquid_name break
   # @liquid_summary
-  #   Stops a [`for` loop](/api/liquid/tags/for) from iterating.
+  #   Stops a [`for` loop](/docs/api/liquid/tags/for) from iterating.
   # @liquid_syntax
   #   {% break %}
   class Break < Tag
     INTERRUPT = BreakInterrupt.new.freeze
 
-    def self.migrate(_tag_name, _markup, _tokenizer, _parse_context)
-      "" # markup was ignored
-    end
-
     def render_to_output_buffer(context, output)
       context.push_interrupt(INTERRUPT)
       output
     end
   end
-
-  Template.register_tag('break', Break)
 end

lib/liquid/tags/capture.rb

@@ -18,21 +18,6 @@ module Liquid
   class Capture < Block
     Syntax = /(#{VariableSignature}+)/o
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      match = markup.match(Syntax)
-
-      new_markup = match[1]
-
-      # replace scanned over characters with a space to ensure there is a space
-      # to separate the tag name and the variable name
-      new_markup.prepend(" ") if match.begin(0) > 0
-
-      new_body, unknown_tag = migrate_body(tag_name, tokenizer, parse_context)
-      raise SyntaxError if unknown_tag
-
-      [new_markup, new_body]
-    end
-
     def initialize(tag_name, markup, options)
       super
       if markup =~ Syntax
@@ -54,6 +39,4 @@ module Liquid
       true
     end
   end
-
-  Template.register_tag('capture', Capture)
 end

lib/liquid/tags/case.rb

@@ -28,20 +28,6 @@ module Liquid
 
     attr_reader :blocks, :left
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      match = markup.match(/\s*#{Syntax}\s*/o) || raise(SyntaxError)
-
-      new_expression = Expression.lax_migrate(match[1])
-      new_markup = Utils.match_captures_replace(match, { 1 => new_expression })
-
-      # replace scanned over characters with a space to ensure there is a space
-      # to separate the tag name and the variable name
-      new_markup.prepend(" ") if match.begin(0) > 0
-
-      new_body = migrate_body(tag_name, tokenizer, parse_context)
-      [new_markup, new_body]
-    end
-
     def initialize(tag_name, markup, options)
       super
       @blocks = []
@@ -53,37 +39,6 @@ module Liquid
       end
     end
 
-    def self.migrate_body(start_tag_name, tokenizer, parse_context)
-      result = +""
-
-      # body before first `when` delimiter tag is ignored
-      unused_body, delimiter_tag = super(start_tag_name, tokenizer, parse_context)
-      unless delimiter_tag
-        raise NotImplementedError, "TODO: migrate `case` tag with no `when` or `else` tags"
-      end
-
-      result << Utils.migrate_stripped(unused_body) { "" } # just keep whitespace (e.g. newline and indent)
-
-      while delimiter_tag
-        break unless delimiter_tag
-
-        case delimiter_tag.tag_name
-        when "when"
-          new_markup = migrate_when_markup(delimiter_tag.markup)
-          result << delimiter_tag.replaced_markup(new_markup)
-        when "else"
-          result << delimiter_tag.original_tag_string
-        else
-          raise SyntaxError
-        end
-
-        new_body, delimiter_tag = super(start_tag_name, tokenizer, parse_context)
-        result << new_body
-      end
-
-      result
-    end
-
     def parse(tokens)
       body = case_body = new_body
       body = @blocks.last.attachment while parse_body(body, tokens)
@@ -122,7 +77,7 @@ module Liquid
         end
 
         result = Liquid::Utils.to_liquid_value(
-          block.evaluate(context)
+          block.evaluate(context),
         )
 
         if result
@@ -136,25 +91,6 @@ module Liquid
 
     private
 
-    private_class_method def self.migrate_when_markup(unstripped_markup)
-      Utils.migrate_stripped(unstripped_markup) do |markup|
-        match = markup.match(WhenSyntax) || raise(SyntaxError)
-
-        replacements = { 1 => Expression.lax_migrate(match[1]) }
-        if (right = match[2])
-          replacements[2] = migrate_when_markup(right)
-        end
-
-        new_markup = Utils.match_captures_replace(match, replacements)
-
-        # replace scanned over characters with a space to ensure there is a space
-        # to separate the tag name and the variable name
-        new_markup.prepend(" ") if match.begin(0) > 0
-
-        new_markup
-      end
-    end
-
     def record_when_condition(markup)
       body = new_body
 
@@ -187,6 +123,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('case', Case)
 end

lib/liquid/tags/comment.rb

@@ -15,24 +15,6 @@ module Liquid
   #   {% endcomment %}
   # @liquid_syntax_keyword content The content of the comment.
   class Comment < Block
-    def self.migrate(tag_name, _markup, tokenizer, parse_context)
-      new_markup = "" # markup was ignored
-      new_body = migrate_body(tag_name, tokenizer, parse_context)
-      [new_markup, new_body]
-    end
-
-    def self.migrate_body(start_tag_name, tokenizer, parse_context)
-      result = +""
-      loop do
-        new_body, delimiter_tag = super(start_tag_name, tokenizer, parse_context)
-        result << new_body
-        break unless delimiter_tag
-
-        result << delimiter_tag.original_tag_string # unknown tags allowed
-      end
-      result
-    end
-
     def render_to_output_buffer(_context, output)
       output
     end
@@ -43,7 +25,64 @@ module Liquid
     def blank?
       true
     end
-  end
 
-  Template.register_tag('comment', Comment)
+    private
+
+    def parse_body(body, tokenizer)
+      if parse_context.depth >= MAX_DEPTH
+        raise StackLevelError, "Nesting too deep"
+      end
+
+      parse_context.depth += 1
+      comment_tag_depth = 1
+
+      begin
+        # Consume tokens without creating child nodes.
+        # The children tag doesn't require to be a valid Liquid except the comment and raw tag.
+        # The child comment and raw tag must be closed.
+        while (token = tokenizer.send(:shift))
+          tag_name = if tokenizer.for_liquid_tag
+            next if token.empty? || token.match?(BlockBody::WhitespaceOrNothing)
+
+            tag_name_match = BlockBody::LiquidTagToken.match(token)
+
+            next if tag_name_match.nil?
+
+            tag_name_match[1]
+          else
+            token =~ BlockBody::FullToken
+            Regexp.last_match(2)
+          end
+
+          case tag_name
+          when "raw"
+            parse_raw_tag_body(tokenizer)
+          when "comment"
+            comment_tag_depth += 1
+          when "endcomment"
+            comment_tag_depth -= 1
+          end
+
+          if comment_tag_depth.zero?
+            parse_context.trim_whitespace = (token[-3] == WhitespaceControl) unless tokenizer.for_liquid_tag
+            return false
+          end
+        end
+
+        raise_tag_never_closed(block_name)
+      ensure
+        parse_context.depth -= 1
+      end
+
+      false
+    end
+
+    def parse_raw_tag_body(tokenizer)
+      while (token = tokenizer.send(:shift))
+        return if token =~ BlockBody::FullTokenPossiblyInvalid && "endraw" == Regexp.last_match(2)
+      end
+
+      raise_tag_never_closed("raw")
+    end
+  end
 end

lib/liquid/tags/continue.rb

@@ -6,21 +6,15 @@ module Liquid
   # @liquid_category iteration
   # @liquid_name continue
   # @liquid_summary
-  #   Causes a [`for` loop](/api/liquid/tags/for) to skip to the next iteration.
+  #   Causes a [`for` loop](/docs/api/liquid/tags/for) to skip to the next iteration.
   # @liquid_syntax
   #   {% continue %}
   class Continue < Tag
     INTERRUPT = ContinueInterrupt.new.freeze
 
-    def self.migrate(_tag_name, _markup, _tokenizer, _parse_context)
-      "" # markup was ignored
-    end
-
     def render_to_output_buffer(context, output)
       context.push_interrupt(INTERRUPT)
       output
     end
   end
-
-  Template.register_tag('continue', Continue)
 end

lib/liquid/tags/cycle.rb

@@ -6,7 +6,7 @@ module Liquid
   # @liquid_category iteration
   # @liquid_name cycle
   # @liquid_summary
-  #   Loops through a group of strings and outputs them one at a time for each iteration of a [`for` loop](/api/liquid/tags/for).
+  #   Loops through a group of strings and outputs them one at a time for each iteration of a [`for` loop](/docs/api/liquid/tags/for).
   # @liquid_description
   #   The `cycle` tag must be used inside a `for` loop.
   #
@@ -18,57 +18,28 @@ module Liquid
     SimpleSyntax = /\A#{QuotedFragment}+/o
     NamedSyntax  = /\A(#{QuotedFragment})\s*\:\s*(.*)/om
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      new_markup = case markup
-      when NamedSyntax
-        match = Regexp.last_match
-
-        new_name_syntax = Expression.lax_migrate(match[1])
-        new_variables_markup = migrate_variables_from_string(match[2])
-
-        Utils.match_captures_replace(match, 1 => new_name_syntax, 2 => new_variables_markup)
-      when SimpleSyntax
-        match = Regexp.last_match
-        migrate_variables_from_string(markup)
-      else
-        raise SyntaxError
-      end
-
-      # replace scanned over characters with a space to ensure there is a space
-      # to separate the tag name and the variable name
-      new_markup.prepend(" ") if match.begin(0) > 0
-
-      new_markup
-    end
-
-    def self.migrate_variables_from_string(markup)
-      markup.split(',').collect do |var|
-        match = var.match(/\s*(#{QuotedFragment})\s*/o)
-        if match
-          Utils.match_captures_replace(match, 1 => Expression.lax_migrate(match[1]))
-        end
-      end.compact.join(",")
-    end
-
     attr_reader :variables
 
-    # @api private
-    attr_reader :name
-
     def initialize(tag_name, markup, options)
       super
       case markup
       when NamedSyntax
         @variables = variables_from_string(Regexp.last_match(2))
         @name      = parse_expression(Regexp.last_match(1))
+        @is_named = true
       when SimpleSyntax
         @variables = variables_from_string(markup)
         @name      = @variables.to_s
+        @is_named = !@name.match?(/\w+:0x\h{8}/)
       else
         raise SyntaxError, options[:locale].t("errors.syntax.cycle")
       end
     end
 
+    def named?
+      @is_named
+    end
+
     def render_to_output_buffer(context, output)
       context.registers[:cycle] ||= {}
 
@@ -107,6 +78,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('cycle', Cycle)
 end

lib/liquid/tags/decrement.rb

@@ -12,8 +12,8 @@ module Liquid
   #   or [section](/themes/architecture/sections) file that they're created in. However, the variable is shared across
   #   [snippets](/themes/architecture#snippets) included in the file.
   #
-  #   Similarly, variables that are created with `decrement` are independent from those created with [`assign`](/api/liquid/tags/assign)
-  #   and [`capture`](/api/liquid/tags/capture). However, `decrement` and [`increment`](/api/liquid/tags/increment) share
+  #   Similarly, variables that are created with `decrement` are independent from those created with [`assign`](/docs/api/liquid/tags/assign)
+  #   and [`capture`](/docs/api/liquid/tags/capture). However, `decrement` and [`increment`](/docs/api/liquid/tags/increment) share
   #   variables.
   # @liquid_syntax
   #   {% decrement variable_name %}
@@ -21,10 +21,6 @@ module Liquid
   class Decrement < Tag
     attr_reader :variable_name
 
-    def self.migrate(_tag_name, markup, _tokenizer, _parse_context)
-      markup # no characters ignored, it just uses anything for the variable name
-    end
-
     def initialize(tag_name, markup, options)
       super
       @variable_name = markup.strip
@@ -39,6 +35,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('decrement', Decrement)
 end

lib/liquid/tags/echo.rb

@@ -9,10 +9,10 @@ module Liquid
   #   Outputs an expression.
   # @liquid_description
   #   Using the `echo` tag is the same as wrapping an expression in curly brackets (`{{` and `}}`). However, unlike the curly
-  #   bracket method, you can use the `echo` tag inside [`liquid` tags](/api/liquid/tags/liquid).
+  #   bracket method, you can use the `echo` tag inside [`liquid` tags](/docs/api/liquid/tags/liquid).
   #
   #   > Tip:
-  #   > You can use [filters](/api/liquid/filters) on expressions inside `echo` tags.
+  #   > You can use [filters](/docs/api/liquid/filters) on expressions inside `echo` tags.
   # @liquid_syntax
   #   {% liquid
   #     echo expression
@@ -21,10 +21,6 @@ module Liquid
   class Echo < Tag
     attr_reader :variable
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      Variable.migrate(markup, parse_context)
-    end
-
     def initialize(tag_name, markup, parse_context)
       super
       @variable = Variable.new(markup, parse_context)
@@ -40,6 +36,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('echo', Echo)
 end

lib/liquid/tags/for.rb

@@ -9,10 +9,10 @@ module Liquid
   #   Renders an expression for every item in an array.
   # @liquid_description
   #   You can do a maximum of 50 iterations with a `for` loop. If you need to iterate over more than 50 items, then use the
-  #   [`paginate` tag](/api/liquid/tags/paginate) to split the items over multiple pages.
+  #   [`paginate` tag](/docs/api/liquid/tags/paginate) to split the items over multiple pages.
   #
   #   > Tip:
-  #   > Every `for` loop has an associated [`forloop` object](/api/liquid/objects/forloop) with information about the loop.
+  #   > Every `for` loop has an associated [`forloop` object](/docs/api/liquid/objects/forloop) with information about the loop.
   # @liquid_syntax
   #   {% for variable in array %}
   #     expression
@@ -25,16 +25,10 @@ module Liquid
   # @liquid_optional_param range [untyped] A custom numeric range to iterate over.
   # @liquid_optional_param reversed [untyped] Iterate in reverse order.
   class For < Block
-    Syntax = /\A(#{VariableSegment}+)\s+in\s+(#{QuotedFragment}+)(\s*reversed)?/o
+    Syntax = /\A(#{VariableSegment}+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/o
 
     attr_reader :collection_name, :variable_name, :limit, :from
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      new_markup = migrate_with_selected_parser(tag_name, markup, tokenizer, parse_context)
-      new_body = migrate_body(tag_name, tokenizer, parse_context)
-      [new_markup, new_body]
-    end
-
     def initialize(tag_name, markup, options)
       super
       @from = @limit = nil
@@ -59,27 +53,6 @@ module Liquid
       @else_block ? [@for_block, @else_block] : [@for_block]
     end
 
-    def self.migrate_body(start_tag_name, tokenizer, parse_context)
-      result = +""
-
-      new_body, delimiter_tag = super(start_tag_name, tokenizer, parse_context)
-      result << new_body
-
-      else_tag = delimiter_tag
-      else_body = nil
-      while delimiter_tag
-        raise SyntaxError unless delimiter_tag.tag_name == 'else'
-        else_tag = delimiter_tag
-        else_body, delimiter_tag = super(start_tag_name, tokenizer, parse_context)
-      end
-      if else_tag
-        result << else_tag.replaced_markup("") # markup was ignored in else tags
-        result << else_body
-      end
-
-      result
-    end
-
     def unknown_tag(tag, markup, tokens)
       return super unless tag == 'else'
       @else_block = new_body
@@ -99,13 +72,6 @@ module Liquid
 
     protected
 
-    private_class_method def self.lax_migrate(tag_name, markup, tokenizer, parse_context)
-      match = markup.match(Syntax) || raise(SyntaxError)
-      new_collection_name = Expression.lax_migrate(match[2])
-      new_markup = Utils.match_captures_replace(match, { 2 => new_collection_name }.compact)
-      new_markup << Utils.migrate_tag_attributes(markup)
-    end
-
     def lax_parse(markup)
       if markup =~ Syntax
         @variable_name   = Regexp.last_match(1)
@@ -121,10 +87,6 @@ module Liquid
       end
     end
 
-    private_class_method def self.strict_migrate(tag_name, markup, tokenizer, parse_context)
-      markup
-    end
-
     def strict_parse(markup)
       p = Parser.new(markup)
       @variable_name = p.consume(:id)
@@ -239,6 +201,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('for', For)
 end

lib/liquid/tags/if.rb

@@ -20,39 +20,6 @@ module Liquid
 
     attr_reader :blocks
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      new_markup = migrate_with_selected_parser(tag_name, markup, tokenizer, parse_context)
-      new_body = migrate_body(tag_name, tokenizer, parse_context)
-      [new_markup, new_body]
-    end
-
-    def self.migrate_body(start_tag_name, tokenizer, parse_context)
-      result = +""
-
-      loop do
-        new_body, delimiter_tag = super(start_tag_name, tokenizer, parse_context)
-        result << new_body
-
-        break unless delimiter_tag
-
-        case delimiter_tag.tag_name
-        when "else"
-          result << delimiter_tag.replaced_markup("") # markup was ignored on else tags
-        when "elsif"
-          new_markup = migrate_with_selected_parser(delimiter_tag.tag_name, delimiter_tag.markup, tokenizer, parse_context)
-          result << delimiter_tag.replaced_markup(new_markup)
-        else
-          raise SyntaxError
-        end
-      end
-
-      result
-    end
-
-    private_class_method def self.strict_migrate(tag_name, markup, tokenizer, parse_context)
-      markup
-    end
-
     def initialize(tag_name, markup, options)
       super
       @blocks = []
@@ -86,7 +53,7 @@ module Liquid
     def render_to_output_buffer(context, output)
       @blocks.each do |block|
         result = Liquid::Utils.to_liquid_value(
-          block.evaluate(context)
+          block.evaluate(context),
         )
 
         if result
@@ -114,10 +81,6 @@ module Liquid
       Condition.parse_expression(parse_context, markup)
     end
 
-    private_class_method def self.lax_migrate_expression(markup)
-      Expression.lax_migrate(markup)
-    end
-
     def lax_parse(markup)
       expressions = markup.scan(ExpressionsAndOperators)
       raise SyntaxError, options[:locale].t("errors.syntax.if") unless expressions.pop =~ Syntax
@@ -138,40 +101,6 @@ module Liquid
       condition
     end
 
-    private_class_method def self.lax_migrate(tag_name, markup, tokenizer, parse_context)
-      expressions = markup.scan(ExpressionsAndOperators)
-
-      new_markup = lax_migrate_condition(expressions.pop)
-      until expressions.empty?
-        operator = expressions.pop
-        new_left_markup = lax_migrate_condition(expressions.pop)
-        new_markup = new_left_markup << operator << new_markup
-      end
-
-      new_markup
-    end
-
-    private_class_method def self.lax_migrate_condition(markup)
-      Utils.migrate_stripped(markup) do |markup|
-        match = markup.match(Syntax)
-        left = lax_migrate_expression(match[1])
-        op = match[2]
-        right_capture = match[3]
-        if op
-          right = lax_migrate_expression(right_capture) if right_capture
-        elsif right_capture
-          right = "" # remove right capture, since it is ignored with no operator
-        end
-        new_markup = Utils.match_captures_replace(match, { 1 => left, 2 => op, 3 => right }.compact)
-        new_markup.prepend(' ') if match.begin(0) > 0
-        new_markup << ' ' if match.end(0) < markup.length
-        if op && !right # missing right operand missing
-          new_markup << " nil" # replace with nil, which it was semantically treated as
-        end
-        new_markup
-      end
-    end
-
     def strict_parse(markup)
       p = Parser.new(markup)
       condition = parse_binary_comparisons(p)
@@ -182,7 +111,7 @@ module Liquid
     def parse_binary_comparisons(p)
       condition = parse_comparison(p)
       first_condition = condition
-      while (op = (p.id?('and') || p.id?('or')))
+      while (op = p.id?('and') || p.id?('or'))
         child_condition = parse_comparison(p)
         condition.send(op, child_condition)
         condition = child_condition
@@ -206,6 +135,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('if', If)
 end

lib/liquid/tags/ifchanged.rb

@@ -2,15 +2,6 @@
 
 module Liquid
   class Ifchanged < Block
-    def self.migrate(tag_name, _markup, tokenizer, parse_context)
-      new_markup = "" # markup was ignored
-
-      new_body, unknown_tag = migrate_body(tag_name, tokenizer, parse_context)
-      raise SyntaxError if unknown_tag
-
-      [new_markup, new_body]
-    end
-
     def render_to_output_buffer(context, output)
       block_output = +''
       super(context, block_output)
@@ -23,6 +14,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('ifchanged', Ifchanged)
 end

lib/liquid/tags/include.rb

@@ -8,7 +8,7 @@ module Liquid
   # @liquid_summary
   #   Renders a [snippet](/themes/architecture#snippets).
   # @liquid_description
-  #   Inside the snippet, you can access and alter variables that are [created](/api/liquid/tags/variable-tags) outside of the
+  #   Inside the snippet, you can access and alter variables that are [created](/docs/api/liquid/tags/variable-tags) outside of the
   #   snippet.
   # @liquid_syntax
   #   {% include 'filename' %}
@@ -16,7 +16,7 @@ module Liquid
   # @liquid_deprecated
   #   Deprecated because the way that variables are handled reduces performance and makes code harder to both read and maintain.
   #
-  #   The `include` tag has been replaced by [`render`](/api/liquid/tags/render).
+  #   The `include` tag has been replaced by [`render`](/docs/api/liquid/tags/render).
   class Include < Tag
     prepend Tag::Disableable
 
@@ -25,22 +25,6 @@ module Liquid
 
     attr_reader :template_name_expr, :variable_name_expr, :attributes
 
-    def self.migrate(_tag_name, markup, _tokenizer, parse_context)
-      match = markup.match(SYNTAX) || raise(SyntaxError)
-
-      template_name = Expression.lax_migrate(match[1])
-      variable_name = Expression.lax_migrate(match[3]) if match[3]
-
-      new_markup = Utils.match_captures_replace(match, { 1 => template_name, 3 => variable_name }.compact)
-      new_markup << Utils.migrate_tag_attributes(markup)
-
-      # replace scanned over characters with a space to ensure there is a space
-      # to separate the tag name and the variable name
-      new_markup.prepend(" ") if match.begin(0) > 0
-
-      new_markup
-    end
-
     def initialize(tag_name, markup, options)
       super
 
@@ -73,7 +57,7 @@ module Liquid
       partial = PartialCache.load(
         template_name,
         context: context,
-        parse_context: parse_context
+        parse_context: parse_context,
       )
 
       context_variable_name = @alias_name || template_name.split('/').last
@@ -86,9 +70,11 @@ module Liquid
 
       old_template_name = context.template_name
       old_partial       = context.partial
+
       begin
-        context.template_name = template_name
-        context.partial       = true
+        context.template_name = partial.name
+        context.partial = true
+
         context.stack do
           @attributes.each do |key, value|
             context[key] = context.evaluate(value)
@@ -124,6 +110,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('include', Include)
 end

lib/liquid/tags/increment.rb

@@ -12,8 +12,8 @@ module Liquid
   #   or [section](/themes/architecture/sections) file that they're created in. However, the variable is shared across
   #   [snippets](/themes/architecture#snippets) included in the file.
   #
-  #   Similarly, variables that are created with `increment` are independent from those created with [`assign`](/api/liquid/tags/assign)
-  #   and [`capture`](/api/liquid/tags/capture). However, `increment` and [`decrement`](/api/liquid/tags/decrement) share
+  #   Similarly, variables that are created with `increment` are independent from those created with [`assign`](/docs/api/liquid/tags/assign)
+  #   and [`capture`](/docs/api/liquid/tags/capture). However, `increment` and [`decrement`](/docs/api/liquid/tags/decrement) share
   #   variables.
   # @liquid_syntax
   #   {% increment variable_name %}
@@ -21,10 +21,6 @@ module Liquid
   class Increment < Tag
     attr_reader :variable_name
 
-    def self.migrate(_tag_name, markup, _tokenizer, _parse_context)
-      markup # no characters ignored, it just uses anything for the variable name
-    end
-
     def initialize(tag_name, markup, options)
       super
       @variable_name = markup.strip
@@ -39,6 +35,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('increment', Increment)
 end

lib/liquid/tags/inline_comment.rb

@@ -2,10 +2,6 @@
 
 module Liquid
   class InlineComment < Tag
-    def self.migrate(_tag_name, markup, _tokenizer, _parse_context)
-      markup
-    end
-
     def initialize(tag_name, markup, options)
       super
 
@@ -29,6 +25,4 @@ module Liquid
       true
     end
   end
-
-  Template.register_tag('#', InlineComment)
 end

lib/liquid/tags/raw.rb

@@ -14,32 +14,6 @@ module Liquid
   # @liquid_syntax_keyword expression The expression to be output without being rendered.
   class Raw < Block
     Syntax = /\A\s*\z/
-    FullTokenPossiblyInvalid = /\A(.*)#{TagStart}\s*(\w+)\s*(.*)?#{TagEnd}\z/om
-
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      raise SyntaxError unless Syntax.match?(markup)
-
-      new_body = migrate_body(tag_name, tokenizer, parse_context)
-      [markup, new_body]
-    end
-
-    def self.migrate_body(start_tag_name, tokenizer, parse_context)
-      block_delimiter = "end#{start_tag_name}"
-
-      body = +''
-      while (token = tokenizer.shift)
-        match = token.match(FullTokenPossiblyInvalid)
-        if match && block_delimiter == match[2]
-          body << Utils.match_captures_replace(match, { 3 => "" })
-          return body
-        end
-        body << token unless token.empty?
-      end
-
-      raise SyntaxError
-    end
-
-    attr_reader :body
 
     def initialize(tag_name, markup, parse_context)
       super
@@ -50,7 +24,8 @@ module Liquid
     def parse(tokens)
       @body = +''
       while (token = tokens.shift)
-        if token =~ FullTokenPossiblyInvalid && block_delimiter == Regexp.last_match(2)
+        if token =~ BlockBody::FullTokenPossiblyInvalid && block_delimiter == Regexp.last_match(2)
+          parse_context.trim_whitespace = (token[-3] == WhitespaceControl)
           @body << Regexp.last_match(1) if Regexp.last_match(1) != ""
           return
         end
@@ -81,6 +56,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('raw', Raw)
 end

lib/liquid/tags/render.rb

@@ -8,19 +8,19 @@ module Liquid
   # @liquid_summary
   #   Renders a [snippet](/themes/architecture#snippets) or [app block](/themes/architecture/sections/section-schema#render-app-blocks).
   # @liquid_description
-  #   Inside snippets and app blocks, you can't directly access variables that are [created](/api/liquid/tags/variable-tags) outside
-  #   of the snippet or app block. However, you can [specify variables as parameters](/api/liquid/tags/render#render-passing-variables-to-a-snippet)
+  #   Inside snippets and app blocks, you can't directly access variables that are [created](/docs/api/liquid/tags/variable-tags) outside
+  #   of the snippet or app block. However, you can [specify variables as parameters](/docs/api/liquid/tags/render#render-passing-variables-to-a-snippet)
   #   to pass outside variables to snippets.
   #
   #   While you can't directly access created variables, you can access global objects, as well as any objects that are
   #   directly accessible outside the snippet or app block. For example, a snippet or app block inside the [product template](/themes/architecture/templates/product)
-  #   can access the [`product` object](/api/liquid/objects/product), and a snippet or app block inside a [section](/themes/architecture/sections)
-  #   can access the [`section` object](/api/liquid/objects/section).
+  #   can access the [`product` object](/docs/api/liquid/objects/product), and a snippet or app block inside a [section](/themes/architecture/sections)
+  #   can access the [`section` object](/docs/api/liquid/objects/section).
   #
   #   Outside a snippet or app block, you can't access variables created inside the snippet or app block.
   #
   #   > Note:
-  #   > When you render a snippet using the `render` tag, you can't use the [`include` tag](/api/liquid/tags/include)
+  #   > When you render a snippet using the `render` tag, you can't use the [`include` tag](/docs/api/liquid/tags/include)
   #   > inside the snippet.
   # @liquid_syntax
   #   {% render 'filename' %}
@@ -29,22 +29,6 @@ module Liquid
     FOR = 'for'
     SYNTAX = /(#{QuotedString}+)(\s+(with|#{FOR})\s+(#{QuotedFragment}+))?(\s+(?:as)\s+(#{VariableSegment}+))?/o
 
-    def self.migrate(_tag_name, markup, _tokenizer, parse_context)
-      match = markup.match(SYNTAX)
-
-      template_name = Expression.lax_migrate(match[1])
-      variable_name = Expression.lax_migrate(match[4]) if match[4]
-
-      new_markup = Utils.match_captures_replace(match, { 1 => template_name, 4 => variable_name }.compact)
-      new_markup << Utils.migrate_tag_attributes(markup)
-
-      # replace scanned over characters with a space to ensure there is a space
-      # to separate the tag name and the variable name
-      new_markup.prepend(" ") if match.begin(0) > 0
-
-      new_markup
-    end
-
     disable_tags "include"
 
     attr_reader :template_name_expr, :variable_name_expr, :attributes, :alias_name
@@ -85,14 +69,14 @@ module Liquid
       partial = PartialCache.load(
         template_name,
         context: context,
-        parse_context: parse_context
+        parse_context: parse_context,
       )
 
       context_variable_name = @alias_name || template_name.split('/').last
 
       render_partial_func = ->(var, forloop) {
         inner_context               = context.new_isolated_subcontext
-        inner_context.template_name = template_name
+        inner_context.template_name = partial.name
         inner_context.partial       = true
         inner_context['forloop']    = forloop if forloop
 
@@ -124,6 +108,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('render', Render)
 end

lib/liquid/tags/table_row.rb

@@ -11,7 +11,7 @@ module Liquid
   #   The `tablerow` tag must be wrapped in HTML `<table>` and `</table>` tags.
   #
   #   > Tip:
-  #   > Every `tablerow` loop has an associated [`tablerowloop` object](/api/liquid/objects/tablerowloop) with information about the loop.
+  #   > Every `tablerow` loop has an associated [`tablerowloop` object](/docs/api/liquid/objects/tablerowloop) with information about the loop.
   # @liquid_syntax
   #   {% tablerow variable in array %}
   #     expression
@@ -26,20 +26,6 @@ module Liquid
   class TableRow < Block
     Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)/o
 
-    def self.migrate(tag_name, markup, tokenizer, parse_context)
-      match = markup.match(Syntax) || raise(SyntaxError)
-
-      new_collection_name = Expression.lax_migrate(match[2])
-
-      new_markup = Utils.match_captures_replace(match, { 2 => new_collection_name }.compact)
-      new_markup << Utils.migrate_tag_attributes(markup)
-
-      new_body, unknown_tag = migrate_body(tag_name, tokenizer, parse_context)
-      raise SyntaxError if unknown_tag
-
-      [new_markup, new_body]
-    end
-
     attr_reader :variable_name, :collection_name, :attributes
 
     def initialize(tag_name, markup, options)
@@ -59,13 +45,13 @@ module Liquid
     def render_to_output_buffer(context, output)
       (collection = context.evaluate(@collection_name)) || (return '')
 
-      from = @attributes.key?('offset') ? context.evaluate(@attributes['offset']).to_i : 0
-      to   = @attributes.key?('limit')  ? from + context.evaluate(@attributes['limit']).to_i : nil
+      from = @attributes.key?('offset') ? to_integer(context.evaluate(@attributes['offset'])) : 0
+      to = @attributes.key?('limit') ? from + to_integer(context.evaluate(@attributes['limit'])) : nil
 
       collection = Utils.slice_collection(collection, from, to)
       length     = collection.length
 
-      cols = @attributes.key?('cols') ? context.evaluate(@attributes['cols']).to_i : length
+      cols = @attributes.key?('cols') ? to_integer(context.evaluate(@attributes['cols'])) : length
 
       output << "<tr class=\"row1\">\n"
       context.stack do
@@ -79,6 +65,12 @@ module Liquid
           super
           output << '</td>'
 
+          # Handle any interrupts if they exist.
+          if context.interrupt?
+            interrupt = context.pop_interrupt
+            break if interrupt.is_a?(BreakInterrupt)
+          end
+
           if tablerowloop.col_last && !tablerowloop.last
             output << "</tr>\n<tr class=\"row#{tablerowloop.row + 1}\">"
           end
@@ -96,7 +88,13 @@ module Liquid
         super + @node.attributes.values + [@node.collection_name]
       end
     end
-  end
 
-  Template.register_tag('tablerow', TableRow)
+    private
+
+    def to_integer(value)
+      value.to_i
+    rescue NoMethodError
+      raise Liquid::ArgumentError, "invalid integer"
+    end
+  end
 end

lib/liquid/tags/unless.rb

@@ -11,7 +11,7 @@ module Liquid
   #   Renders an expression unless a specific condition is `true`.
   # @liquid_description
   #   > Tip:
-  #   > Similar to the [`if` tag](/api/liquid/tags/if), you can use `elsif` to add more conditions to an `unless` tag.
+  #   > Similar to the [`if` tag](/docs/api/liquid/tags/if), you can use `elsif` to add more conditions to an `unless` tag.
   # @liquid_syntax
   #   {% unless condition %}
   #     expression
@@ -23,7 +23,7 @@ module Liquid
       # First condition is interpreted backwards ( if not )
       first_block = @blocks.first
       result = Liquid::Utils.to_liquid_value(
-        first_block.evaluate(context)
+        first_block.evaluate(context),
       )
 
       unless result
@@ -33,7 +33,7 @@ module Liquid
       # After the first condition unless works just like if
       @blocks[1..-1].each do |block|
         result = Liquid::Utils.to_liquid_value(
-          block.evaluate(context)
+          block.evaluate(context),
         )
 
         if result
@@ -44,6 +44,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('unless', Unless)
 end

lib/liquid/template.rb

@@ -15,45 +15,9 @@ module Liquid
   #   template.render('user_name' => 'bob')
   #
   class Template
-    attr_accessor :root
+    attr_accessor :root, :name
     attr_reader :resource_limits, :warnings
 
-    class TagRegistry
-      include Enumerable
-
-      def initialize
-        @tags  = {}
-        @cache = {}
-      end
-
-      def [](tag_name)
-        return nil unless @tags.key?(tag_name)
-        return @cache[tag_name] if Liquid.cache_classes
-
-        lookup_class(@tags[tag_name]).tap { |o| @cache[tag_name] = o }
-      end
-
-      def []=(tag_name, klass)
-        @tags[tag_name]  = klass.name
-        @cache[tag_name] = klass
-      end
-
-      def delete(tag_name)
-        @tags.delete(tag_name)
-        @cache.delete(tag_name)
-      end
-
-      def each(&block)
-        @tags.each(&block)
-      end
-
-      private
-
-      def lookup_class(name)
-        Object.const_get(name)
-      end
-    end
-
     attr_reader :profiler
 
     class << self
@@ -61,68 +25,88 @@ module Liquid
       # :lax acts like liquid 2.5 and silently ignores malformed tags in most cases.
       # :warn is the default and will give deprecation warnings when invalid syntax is used.
       # :strict will enforce correct syntax.
-      attr_accessor :error_mode
-      Template.error_mode = :lax
-
-      attr_accessor :default_exception_renderer
-      Template.default_exception_renderer = lambda do |exception|
-        exception
+      def error_mode=(mode)
+        Deprecations.warn("Template.error_mode=", "Environment#error_mode=")
+        Environment.default.error_mode = mode
       end
 
-      attr_accessor :file_system
-      Template.file_system = BlankFileSystem.new
+      def error_mode
+        Environment.default.error_mode
+      end
 
-      attr_accessor :tags
-      Template.tags = TagRegistry.new
-      private :tags=
+      def default_exception_renderer=(renderer)
+        Deprecations.warn("Template.default_exception_renderer=", "Environment#exception_renderer=")
+        Environment.default.exception_renderer = renderer
+      end
+
+      def default_exception_renderer
+        Environment.default.exception_renderer
+      end
+
+      def file_system=(file_system)
+        Deprecations.warn("Template.file_system=", "Environment#file_system=")
+        Environment.default.file_system = file_system
+      end
+
+      def file_system
+        Environment.default.file_system
+      end
+
+      def tags
+        Environment.default.tags
+      end
 
       def register_tag(name, klass)
-        tags[name.to_s] = klass
+        Deprecations.warn("Template.register_tag", "Environment#register_tag")
+        Environment.default.register_tag(name, klass)
       end
 
       # Pass a module with filter methods which should be available
       # to all liquid views. Good for registering the standard library
       def register_filter(mod)
-        StrainerFactory.add_global_filter(mod)
+        Deprecations.warn("Template.register_filter", "Environment#register_filter")
+        Environment.default.register_filter(mod)
       end
 
-      attr_accessor :default_resource_limits
-      Template.default_resource_limits = {}
-      private :default_resource_limits=
+      private def default_resource_limits=(limits)
+        Deprecations.warn("Template.default_resource_limits=", "Environment#default_resource_limits=")
+        Environment.default.default_resource_limits = limits
+      end
+
+      def default_resource_limits
+        Environment.default.default_resource_limits
+      end
 
       # creates a new <tt>Template</tt> object from liquid source code
       # To enable profiling, pass in <tt>profile: true</tt> as an option.
       # See Liquid::Profiler for more information
       def parse(source, options = {})
-        new.parse(source, options)
-      end
-
-      def migrate(source, parse_options = {})
-        parse(source, parse_options) # raise if source has syntax errors
-        new.migrate(source, parse_options)
+        environment = options[:environment] || Environment.default
+        new(environment: environment).parse(source, options)
       end
     end
 
-    def initialize
+    def initialize(environment: Environment.default)
+      @environment = environment
       @rethrow_errors  = false
-      @resource_limits = ResourceLimits.new(Template.default_resource_limits)
+      @resource_limits = ResourceLimits.new(environment.default_resource_limits)
     end
 
     # Parse source code.
     # Returns self for easy chaining
     def parse(source, options = {})
       parse_context = configure_options(options)
+      source = source.to_s.to_str
+
+      unless source.valid_encoding?
+        raise TemplateEncodingError, parse_context.locale.t("errors.syntax.invalid_template_encoding")
+      end
+
       tokenizer     = parse_context.new_tokenizer(source, start_line_number: @line_numbers && 1)
       @root         = Document.parse(tokenizer, parse_context)
       self
     end
 
-    def migrate(source, parse_options = {})
-      parse_context = configure_options(parse_options.merge(disable_liquid_c_nodes: true))
-      tokenizer     = parse_context.new_tokenizer(source, start_line_number: @line_numbers && 1)
-      Document.migrate(tokenizer, parse_context)
-    end
-
     def registers
       @registers ||= {}
     end
@@ -167,11 +151,11 @@ module Liquid
         c
       when Liquid::Drop
         drop         = args.shift
-        drop.context = Context.new([drop, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits)
+        drop.context = Context.new([drop, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits, {}, @environment)
       when Hash
-        Context.new([args.shift, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits)
+        Context.new([args.shift, assigns], instance_assigns, registers, @rethrow_errors, @resource_limits, {}, @environment)
       when nil
-        Context.new(assigns, instance_assigns, registers, @rethrow_errors, @resource_limits)
+        Context.new(assigns, instance_assigns, registers, @rethrow_errors, @resource_limits, {}, @environment)
       else
         raise ArgumentError, "Expected Hash or Liquid::Context as parameter"
       end
@@ -200,6 +184,8 @@ module Liquid
         @profiler = context.profiler = Liquid::Profiler.new
       end
 
+      context.template_name ||= name
+
       begin
         # render the nodelist.
         @root.render_to_output_buffer(context, output || +'')
@@ -229,8 +215,14 @@ module Liquid
       @options      = options
       @profiling    = profiling
       @line_numbers = options[:line_numbers] || @profiling
-      parse_context = options.is_a?(ParseContext) ? options : ParseContext.new(options)
-      @warnings     = parse_context.warnings
+      parse_context = if options.is_a?(ParseContext)
+        options
+      else
+        opts = options.key?(:environment) ? options : options.merge(environment: @environment)
+        ParseContext.new(opts)
+      end
+
+      @warnings = parse_context.warnings
       parse_context
     end
 

lib/liquid/tokenizer.rb

@@ -5,7 +5,7 @@ module Liquid
     attr_reader :line_number, :for_liquid_tag
 
     def initialize(source, line_numbers = false, line_number: nil, for_liquid_tag: false)
-      @source         = source.to_s.to_str
+      @source         = source
       @line_number    = line_number || (line_numbers ? 1 : nil)
       @for_liquid_tag = for_liquid_tag
       @offset         = 0
@@ -25,10 +25,6 @@ module Liquid
       token
     end
 
-    def more?
-      @offset < @tokens.length
-    end
-
     private
 
     def tokenize

lib/liquid/utils.rb

@@ -89,48 +89,5 @@ module Liquid
       # Otherwise return the object itself
       obj
     end
-
-    def self.migrate_stripped(markup)
-      match = markup.match(/\A\s*(.*?)\s*\z/m)
-      new_markup = yield match[1]
-      Utils.match_captures_replace(match, 1 => new_markup)
-    end
-
-    def self.migrate_tag_attributes(markup)
-      attributes = []
-      markup.scan(/\s*,?\s*#{TagAttributes}/) do
-        tag_match = Regexp.last_match
-        new_value_markup = Expression.lax_migrate(tag_match[2])
-        attribute_markup = Utils.match_captures_replace(tag_match, { 2 => new_value_markup })
-        unless attribute_markup.match?(/\A[,\s]/)
-          attribute_markup.prepend(", ")
-        end
-        attributes << attribute_markup
-      end
-      return "" if attributes.empty?
-      attributes.join
-    end
-
-    # @api private
-    def self.match_capture_replace(match, capture_number, replacement_string)
-      match_captures_replace(match, { capture_number => replacement_string })
-    end
-
-    def self.match_captures_replace(match, replacements = {})
-      new_string = match[0].dup
-      capture_numbers = replacements.keys
-      unless capture_numbers.all?(Integer)
-        raise TypeError, "Currently, only numbered captures are supported"
-      end
-      # replace from later captures first, to avoid affecting the position for following replacements
-      match_begin = match.begin(0)
-      capture_numbers.sort.reverse_each do |capture_number|
-        replacement_string = replacements.fetch(capture_number)
-        capture_start = match.begin(capture_number)
-        capture_length = match.end(capture_number) - capture_start
-        new_string[capture_start - match_begin, capture_length] = replacement_string
-      end
-      new_string
-    end
   end
 end

lib/liquid/variable.rb

@@ -41,79 +41,6 @@ module Liquid
       "in \"{{#{markup}}}\""
     end
 
-    STRICT_PARSE_CONTEXT = ParseContext.new(error_mode: :strict)
-    private_constant :STRICT_PARSE_CONTEXT
-
-    def self.migrate(markup, parse_context)
-      new(markup, STRICT_PARSE_CONTEXT)
-      # TODO: migrate non-integer range expression literals
-      markup
-    rescue Liquid::SyntaxError
-      raise if parse_context.error_mode == :strict
-      lax_migrate(markup, parse_context)
-    end
-
-    def self.lax_migrate(markup, parse_context)
-      # unanchored match that may skip over characters preceding the name expression
-      markup_match = markup.match(MarkupWithQuotedFragment)
-      unless markup_match
-        # Treated as a blank variable (e.g. `{{ -}}`), which outputs nothing
-        # but may still have an effect on whitespace trimming
-        return ""
-      end
-
-      name_markup = markup_match[1]
-      filters_markup = markup_match[2]
-
-      new_name_markup = Expression.lax_migrate(name_markup)
-
-      new_filter_markup = ""
-      # unanchored match that may skip over characters preceding the pipe for the first filter
-      if (filters_match = filters_markup.match(/\s*#{FilterMarkupRegex}/o))
-        filters = filters_match[1].scan(FilterParser) # may skip over unterminated quote characters
-        filters.map! do |f|
-          filter_match = f.match(/\A(\s*)\W*(\w+)(\s*)/)
-          next unless filter_match
-
-          # omit non-word characters preceding the filter name that the lax parser skips over
-          transformed_filter = +"#{filter_match[1]}#{filter_match[2]}#{filter_match[3]}"
-
-          filter_args = []
-          f.scan(/#{FilterArgsRegex}\s*/o) do # may skip over characters before the argument separator
-            filter_arg_match = Regexp.last_match
-            new_filter_arg = lax_migrate_filter_argument(filter_arg_match[1])
-            filter_arg_string = Utils.match_captures_replace(filter_arg_match, 1 => new_filter_arg)
-            filter_arg_string = filter_arg_string[1...] # remove separator character
-            filter_args << filter_arg_string
-          end
-
-          unless filter_args.empty?
-            transformed_filter << ":" << filter_args.join(",")
-          end
-
-          transformed_filter
-        end
-        filters.compact!
-        new_filters_markup = filters.join('|')
-
-        # include pipe separator along with whitespace surrounding it
-        new_filter_markup = Utils.match_captures_replace(filters_match, 1 => new_filters_markup)
-      end
-
-      new_markup = Utils.match_captures_replace(markup_match, 1 => new_name_markup, 2 => new_filter_markup)
-      new_markup.prepend(" ") if markup_match.begin(0) > 0
-      new_markup
-    end
-
-    def self.lax_migrate_filter_argument(unparsed_arg)
-      if (match = unparsed_arg.match(JustTagAttributes))
-        new_value_markup = Expression.lax_migrate(match[2])
-        Utils.match_captures_replace(match, 2 => new_value_markup)
-      else
-        Expression.lax_migrate(unparsed_arg)
-      end
-    end
-
     def lax_parse(markup)
       @filters = []
       return unless markup =~ MarkupWithQuotedFragment
@@ -141,7 +68,7 @@ module Liquid
       @name = parse_context.parse_expression(p.expression)
       while p.consume?(:pipe)
         filtername = p.consume(:id)
-        filterargs = p.consume?(:colon) ? parse_filterargs(p) : []
+        filterargs = p.consume?(:colon) ? parse_filterargs(p) : Const::EMPTY_ARRAY
         @filters << parse_filter_expressions(filtername, filterargs)
       end
       p.consume(:end_of_string)

lib/liquid/variable_lookup.rb

@@ -10,43 +10,6 @@ module Liquid
       new(markup)
     end
 
-    LITERALS = Expression::LITERALS.keys.freeze
-    private_constant :LITERALS
-
-    def self.lax_migrate(markup)
-      new_markup = nil
-      last_match = nil
-      first_match = nil
-      markup.scan(VariableParser) do |lookup|
-        last_match = Regexp.last_match
-        first_match ||= last_match
-        new_markup ||= +""
-        if lookup&.start_with?('[') && lookup&.end_with?(']')
-          new_markup << "[" << Expression.lax_migrate(lookup[1..-2]) << "]"
-        elsif !lookup.match?(/\A#{Liquid::Lexer::IDENTIFIER}\z/)
-          # quote non-strictly valid identifiers
-          new_markup << "['" << lookup << "']"
-        else
-          new_markup << "." unless new_markup.empty?
-          new_markup << lookup
-        end
-      end
-
-      case new_markup
-      when nil
-        # `markup.scan(VariableParser)` may skip over all characters
-        new_markup ||= " nil "
-      when Expression::INTEGERS_REGEX, Expression::RANGES_REGEX, Expression::FLOATS_REGEX, *LITERALS
-        # Quote variable lookups that match literals after characters are skipped by regex scanning
-        new_markup = "['#{new_markup}']"
-      else
-        new_markup.prepend(" ") if first_match.begin(0) > 0
-        new_markup << ' ' if last_match.end(0) < markup.length
-      end
-
-      new_markup
-    end
-
     def initialize(markup)
       lookups = markup.scan(VariableParser)
 

lib/liquid/version.rb

@@ -2,5 +2,5 @@
 # frozen_string_literal: true
 
 module Liquid
-  VERSION = "5.4.0"
+  VERSION = "5.6.0.rc1"
 end

liquid.gemspec

@@ -17,7 +17,7 @@ Gem::Specification.new do |s|
   s.license     = "MIT"
   # s.description = "A secure, non-evaling end user template engine with aesthetic markup."
 
-  s.required_ruby_version     = ">= 2.7.0"
+  s.required_ruby_version     = ">= 3.0.0"
   s.required_rubygems_version = ">= 1.3.7"
 
   s.metadata['allowed_push_host'] = 'https://rubygems.org'
@@ -28,6 +28,9 @@ Gem::Specification.new do |s|
 
   s.require_path = "lib"
 
+  s.add_dependency("strscan")
+  s.add_dependency("bigdecimal")
+
   s.add_development_dependency('rake', '~> 13.0')
   s.add_development_dependency('minitest')
 end

performance/benchmark.rb

@@ -3,7 +3,9 @@
 require 'benchmark/ips'
 require_relative 'theme_runner'
 
-Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
+RubyVM::YJIT.enable if defined?(RubyVM::YJIT)
+Liquid::Environment.default.error_mode = ARGV.first.to_sym if ARGV.first
+
 profiler = ThemeRunner.new
 
 Benchmark.ips do |x|

performance/shopify/database.rb

@@ -49,8 +49,3 @@ module Database
     end
   end
 end
-
-if __FILE__ == $PROGRAM_NAME
-  p(Database.tables['collections']['frontpage'].keys)
-  # p Database.tables['blog']['articles']
-end

performance/shopify/liquid.rb

@@ -11,11 +11,12 @@ require_relative 'shop_filter'
 require_relative 'tag_filter'
 require_relative 'weight_filter'
 
-Liquid::Template.register_tag('paginate', Paginate)
-Liquid::Template.register_tag('form', CommentForm)
+default_environment = Liquid::Environment.default
+default_environment.register_tag('paginate', Paginate)
+default_environment.register_tag('form', CommentForm)
 
-Liquid::Template.register_filter(JsonFilter)
-Liquid::Template.register_filter(MoneyFilter)
-Liquid::Template.register_filter(WeightFilter)
-Liquid::Template.register_filter(ShopFilter)
-Liquid::Template.register_filter(TagFilter)
+default_environment.register_filter(JsonFilter)
+default_environment.register_filter(MoneyFilter)
+default_environment.register_filter(WeightFilter)
+default_environment.register_filter(ShopFilter)
+default_environment.register_filter(TagFilter)

performance/shopify/paginate.rb

@@ -45,8 +45,8 @@ class Paginate < Liquid::Block
 
       pagination['items']      = collection_size
       pagination['pages']      = page_count - 1
-      pagination['previous']   = link('&laquo; Previous', current_page - 1)  unless 1 >= current_page
-      pagination['next']       = link('Next &raquo;', current_page + 1)      unless page_count <= current_page + 1
+      pagination['previous']   = link('&laquo; Previous', current_page - 1)  if 1 < current_page
+      pagination['next']       = link('Next &raquo;', current_page + 1)      if page_count > current_page + 1
       pagination['parts']      = []
 
       hellip_break = false

performance/unit/lexer_benchmark.rb

@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+require "benchmark/ips"
+
+# benchmark liquid lexing
+
+require 'liquid'
+
+RubyVM::YJIT.enable
+
+EXPRESSIONS = [
+  "foo[1..2].baz",
+  "12.0",
+  "foo.bar.based",
+  "21 - 62",
+  "foo.bar.baz",
+  "foo > 12",
+  "foo < 12",
+  "foo <= 12",
+  "foo >= 12",
+  "foo <> 12",
+  "foo == 12",
+  "foo != 12",
+  "foo contains 12",
+  "foo contains 'bar'",
+  "foo != 'bar'",
+  "'foo' contains 'bar'",
+  '234089',
+  "foo | default: -1",
+]
+
+EXPRESSIONS.each do |expr|
+  lexer_1_result = Liquid::Lexer1.new(expr).tokenize
+  lexer_2_result = Liquid::Lexer2.new(expr).tokenize
+
+  next if lexer_1_result == lexer_2_result
+
+  warn "Lexer1 and Lexer2 results are different for expression: #{expr}"
+  warn "expected: #{lexer_1_result}"
+  warn "got: #{lexer_2_result}"
+  abort
+end
+
+Benchmark.ips do |x|
+  x.config(time: 10, warmup: 5)
+
+  x.report("Liquid::Lexer1#tokenize") do
+    EXPRESSIONS.each do |expr|
+      l = Liquid::Lexer1.new(expr)
+      l.tokenize
+    end
+  end
+
+  x.report("Liquid::Lexer2#tokenize") do
+    EXPRESSIONS.each do |expr|
+      l = Liquid::Lexer2.new(expr)
+      l.tokenize
+    end
+  end
+
+  x.compare!
+end

test/integration/assign_test.rb

@@ -14,19 +14,25 @@ class AssignTest < Minitest::Test
   end
 
   def test_assigned_variable
-    assert_template_result('.foo.',
+    assert_template_result(
+      '.foo.',
       '{% assign foo = values %}.{{ foo[0] }}.',
-      { 'values' => %w(foo bar baz) })
+      { 'values' => %w(foo bar baz) },
+    )
 
-    assert_template_result('.bar.',
+    assert_template_result(
+      '.bar.',
       '{% assign foo = values %}.{{ foo[1] }}.',
-      { 'values' => %w(foo bar baz) })
+      { 'values' => %w(foo bar baz) },
+    )
   end
 
   def test_assign_with_filter
-    assert_template_result('.bar.',
+    assert_template_result(
+      '.bar.',
       '{% assign foo = values | split: "," %}.{{ foo[1] }}.',
-      { 'values' => "foo,bar,baz" })
+      { 'values' => "foo,bar,baz" },
+    )
   end
 
   def test_assign_syntax_error
@@ -34,8 +40,11 @@ class AssignTest < Minitest::Test
   end
 
   def test_assign_uses_error_mode
-    assert_match_syntax_error("Expected dotdot but found pipe in ",
-      "{% assign foo = ('X' | downcase) %}", error_mode: :strict)
+    assert_match_syntax_error(
+      "Expected dotdot but found pipe in ",
+      "{% assign foo = ('X' | downcase) %}",
+      error_mode: :strict,
+    )
     assert_template_result("", "{% assign foo = ('X' | downcase) %}", error_mode: :lax)
   end
 

test/integration/blank_test.rb

@@ -57,9 +57,11 @@ class BlankTest < Minitest::Test
 
   def test_nested_blocks_are_blank_but_only_if_all_children_are
     assert_template_result("", wrap(wrap(" ")))
-    assert_template_result("\n       but this is not " * (N + 1),
+    assert_template_result(
+      "\n       but this is not " * (N + 1),
       wrap('{% if true %} {% comment %} this is blank {% endcomment %} {% endif %}
-      {% if true %} but this is not {% endif %}'))
+      {% if true %} but this is not {% endif %}'),
+    )
   end
 
   def test_assigns_are_blank
@@ -89,12 +91,21 @@ class BlankTest < Minitest::Test
   end
 
   def test_include_is_blank
-    assert_template_result("foobar" * (N + 1), wrap("{% include 'foobar' %}"),
-      partials: { 'foobar' => 'foobar' })
-    assert_template_result(" foobar " * (N + 1), wrap("{% include ' foobar ' %}"),
-      partials: { ' foobar ' => ' foobar ' })
-    assert_template_result("   " * (N + 1), wrap(" {% include ' ' %} "),
-      partials: { ' ' => ' ' })
+    assert_template_result(
+      "foobar" * (N + 1),
+      wrap("{% include 'foobar' %}"),
+      partials: { 'foobar' => 'foobar' },
+    )
+    assert_template_result(
+      " foobar " * (N + 1),
+      wrap("{% include ' foobar ' %}"),
+      partials: { ' foobar ' => ' foobar ' },
+    )
+    assert_template_result(
+      "   " * (N + 1),
+      wrap(" {% include ' ' %} "),
+      partials: { ' ' => ' ' },
+    )
   end
 
   def test_case_is_blank

test/integration/context_test.rb

@@ -36,6 +36,24 @@ class Category
   end
 end
 
+class ProductsDrop < Liquid::Drop
+  def initialize(products)
+    @products = products
+  end
+
+  def size
+    @products.size
+  end
+
+  def to_liquid
+    if @context["forloop"]
+      @products.first(@context["forloop"].length)
+    else
+      @products
+    end
+  end
+end
+
 class CategoryDrop < Liquid::Drop
   attr_accessor :category, :context
 
@@ -121,14 +139,23 @@ class ContextTest < Minitest::Test
   end
 
   def test_length_query
-    assert_template_result("true", "{% if numbers.size == 4 %}true{% endif %}",
-      { "numbers" => [1, 2, 3, 4] })
+    assert_template_result(
+      "true",
+      "{% if numbers.size == 4 %}true{% endif %}",
+      { "numbers" => [1, 2, 3, 4] },
+    )
 
-    assert_template_result("true", "{% if numbers.size == 4 %}true{% endif %}",
-      { "numbers" => { 1 => 1, 2 => 2, 3 => 3, 4 => 4 } })
+    assert_template_result(
+      "true",
+      "{% if numbers.size == 4 %}true{% endif %}",
+      { "numbers" => { 1 => 1, 2 => 2, 3 => 3, 4 => 4 } },
+    )
 
-    assert_template_result("true", "{% if numbers.size == 1000 %}true{% endif %}",
-      { "numbers" => { 1 => 1, 2 => 2, 3 => 3, 4 => 4, 'size' => 1000 } })
+    assert_template_result(
+      "true",
+      "{% if numbers.size == 1000 %}true{% endif %}",
+      { "numbers" => { 1 => 1, 2 => 2, 3 => 3, 4 => 4, 'size' => 1000 } },
+    )
   end
 
   def test_hyphenated_variable
@@ -228,12 +255,14 @@ class ContextTest < Minitest::Test
   end
 
   def test_hash_to_array_transition
-    assigns = { 'colors' => {
-      'Blue' => ['003366', '336699', '6699CC', '99CCFF'],
-      'Green' => ['003300', '336633', '669966', '99CC99'],
-      'Yellow' => ['CC9900', 'FFCC00', 'FFFF99', 'FFFFCC'],
-      'Red' => ['660000', '993333', 'CC6666', 'FF9999'],
-    } }
+    assigns = {
+      'colors' => {
+        'Blue' => ['003366', '336699', '6699CC', '99CCFF'],
+        'Green' => ['003300', '336633', '669966', '99CC99'],
+        'Yellow' => ['CC9900', 'FFCC00', 'FFFF99', 'FFFFCC'],
+        'Red' => ['660000', '993333', 'CC6666', 'FF9999'],
+      },
+    }
 
     assert_template_result("003366", "{{ colors.Blue[0] }}", assigns)
     assert_template_result("FF9999", "{{ colors.Red[3] }}", assigns)
@@ -262,7 +291,7 @@ class ContextTest < Minitest::Test
     assigns = { 'product' => { 'variants' => [{ 'title' => 'draft151cm' }, { 'title' => 'element151cm' }] } }
     assert_template_result("draft151cm", '{{ product["variants"][0]["title"] }}', assigns)
     assert_template_result("element151cm", '{{ product["variants"][1]["title"] }}', assigns)
-    assert_template_result("draft151cm", '{{ product["variants"][0]["title"] }}', assigns)
+    assert_template_result("draft151cm", '{{ product["variants"].first["title"] }}', assigns)
     assert_template_result("element151cm", '{{ product["variants"].last["title"] }}', assigns)
   end
 
@@ -410,10 +439,12 @@ class ContextTest < Minitest::Test
   def test_nested_lambda_is_called_once
     @global = 0
 
-    @context['callcount'] = { "lambda" => proc {
-                                            @global += 1
-                                            @global.to_s
-                                          } }
+    @context['callcount'] = {
+      "lambda" => proc {
+                    @global += 1
+                    @global.to_s
+                  },
+    }
 
     assert_equal('1', @context['callcount.lambda'])
     assert_equal('1', @context['callcount.lambda'])
@@ -423,10 +454,11 @@ class ContextTest < Minitest::Test
   def test_lambda_in_array_is_called_once
     @global = 0
 
-    @context['callcount'] = [1, 2, proc {
-                                     @global += 1
-                                     @global.to_s
-                                   }, 4, 5]
+    p = proc {
+      @global += 1
+      @global.to_s
+    }
+    @context['callcount'] = [1, 2, p, 4, 5]
 
     assert_equal('1', @context['callcount[2]'])
     assert_equal('1', @context['callcount[2]'])
@@ -473,7 +505,7 @@ class ContextTest < Minitest::Test
   def test_static_environments_are_read_with_lower_priority_than_environments
     context = Context.build(
       static_environments: { 'shadowed' => 'static', 'unshadowed' => 'static' },
-      environments: { 'shadowed' => 'dynamic' }
+      environments: { 'shadowed' => 'dynamic' },
     )
 
     assert_equal('dynamic', context['shadowed'])
@@ -621,6 +653,40 @@ class ContextTest < Minitest::Test
     assert_equal(:my_value, c.registers[:my_register])
   end
 
+  def test_variable_to_liquid_returns_contextual_drop
+    context = {
+      "products" => ProductsDrop.new(["A", "B", "C", "D", "E"]),
+    }
+
+    template = Liquid::Template.parse(<<~LIQUID)
+      {%- for i in (1..3) -%}
+        for_loop_products_count: {{ products | size }}
+      {% endfor %}
+
+      unscoped_products_count: {{ products | size }}
+    LIQUID
+
+    result = template.render(context)
+
+    assert_includes(result, "for_loop_products_count: 3")
+    assert_includes(result, "unscoped_products_count: 5")
+  end
+
+  def test_new_isolated_context_inherits_parent_environment
+    global_environment = Liquid::Environment.build(tags: {})
+    context = Context.build(environment: global_environment)
+
+    subcontext = context.new_isolated_subcontext
+    assert_equal(global_environment, subcontext.environment)
+  end
+
+  def test_newly_built_context_inherits_parent_environment
+    global_environment = Liquid::Environment.build(tags: {})
+    context = Context.build(environment: global_environment)
+    assert_equal(global_environment, context.environment)
+    assert(context.environment.tags.each.to_a.empty?)
+  end
+
   private
 
   def assert_no_object_allocations

test/integration/error_handling_test.rb

@@ -105,7 +105,8 @@ class ErrorHandlingTest < Minitest::Test
   end
 
   def test_parsing_warn_with_line_numbers_adds_numbers_to_lexer_errors
-    template = Liquid::Template.parse('
+    template = Liquid::Template.parse(
+      '
         foobar
 
         {% if 1 =! 2 %}ok{% endif %}
@@ -113,15 +114,19 @@ class ErrorHandlingTest < Minitest::Test
         bla
             ',
       error_mode: :warn,
-      line_numbers: true)
+      line_numbers: true,
+    )
 
-    assert_equal(['Liquid syntax error (line 4): Unexpected character = in "1 =! 2"'],
-      template.warnings.map(&:message))
+    assert_equal(
+      ['Liquid syntax error (line 4): Unexpected character = in "1 =! 2"'],
+      template.warnings.map(&:message),
+    )
   end
 
   def test_parsing_strict_with_line_numbers_adds_numbers_to_lexer_errors
     err = assert_raises(SyntaxError) do
-      Liquid::Template.parse('
+      Liquid::Template.parse(
+        '
           foobar
 
           {% if 1 =! 2 %}ok{% endif %}
@@ -129,7 +134,8 @@ class ErrorHandlingTest < Minitest::Test
           bla
                 ',
         error_mode: :strict,
-        line_numbers: true)
+        line_numbers: true,
+      )
     end
 
     assert_equal('Liquid syntax error (line 4): Unexpected character = in "1 =! 2"', err.message)
@@ -197,20 +203,34 @@ class ErrorHandlingTest < Minitest::Test
   end
 
   def test_setting_default_exception_renderer
-    old_exception_renderer = Liquid::Template.default_exception_renderer
     exceptions = []
-    Liquid::Template.default_exception_renderer = ->(e) {
+    default_exception_renderer = ->(e) {
       exceptions << e
       ''
     }
-    template = Liquid::Template.parse('This is a runtime error: {{ errors.argument_error }}')
+
+    env = Liquid::Environment.build(exception_renderer: default_exception_renderer)
+    template = Liquid::Template.parse('This is a runtime error: {{ errors.argument_error }}', environment: env)
 
     output = template.render('errors' => ErrorDrop.new)
 
     assert_equal('This is a runtime error: ', output)
     assert_equal([Liquid::ArgumentError], template.errors.map(&:class))
-  ensure
-    Liquid::Template.default_exception_renderer = old_exception_renderer if old_exception_renderer
+  end
+
+  def test_setting_exception_renderer_on_environment
+    exceptions = []
+    exception_renderer = ->(e) do
+      exceptions << e
+      ''
+    end
+
+    environment = Liquid::Environment.build(exception_renderer: exception_renderer)
+    template = Liquid::Template.parse('This is a runtime error: {{ errors.argument_error }}', environment: environment)
+    output = template.render('errors' => ErrorDrop.new)
+
+    assert_equal('This is a runtime error: ', output)
+    assert_equal([Liquid::ArgumentError], template.errors.map(&:class))
   end
 
   def test_exception_renderer_exposing_non_liquid_error
@@ -236,16 +256,10 @@ class ErrorHandlingTest < Minitest::Test
   end
 
   def test_included_template_name_with_line_numbers
-    old_file_system = Liquid::Template.file_system
+    environment = Liquid::Environment.build(file_system: TestFileSystem.new)
+    template = Liquid::Template.parse("Argument error:\n{% include 'product' %}", line_numbers: true, environment: environment)
+    page     = template.render('errors' => ErrorDrop.new)
 
-    begin
-      Liquid::Template.file_system = TestFileSystem.new
-
-      template = Liquid::Template.parse("Argument error:\n{% include 'product' %}", line_numbers: true)
-      page     = template.render('errors' => ErrorDrop.new)
-    ensure
-      Liquid::Template.file_system = old_file_system
-    end
     assert_equal("Argument error:\nLiquid error (product line 1): argument error", page)
     assert_equal("product", template.errors.first.template_name)
   end
@@ -257,4 +271,81 @@ class ErrorHandlingTest < Minitest::Test
     output = Liquid::Template.parse("{% assign x = 0 %}{% if 1 < '2' %}{% assign x = 3 %}{% endif %}{{ x }}").render
     assert_equal("0", output)
   end
+
+  def test_syntax_error_is_raised_with_template_name
+    file_system = StubFileSystem.new("snippet" => "1\n2\n{{ 1")
+
+    context = Liquid::Context.build(
+      registers: { file_system: file_system },
+    )
+
+    template = Template.parse(
+      '{% render "snippet" %}',
+      line_numbers: true,
+    )
+    template.name = "template/index"
+
+    assert_equal(
+      "Liquid syntax error (snippet line 3): Variable '{{' was not properly terminated with regexp: /\\}\\}/",
+      template.render(context),
+    )
+  end
+
+  def test_syntax_error_is_raised_with_template_name_from_template_factory
+    file_system = StubFileSystem.new("snippet" => "1\n2\n{{ 1")
+
+    context = Liquid::Context.build(
+      registers: {
+        file_system: file_system,
+        template_factory: StubTemplateFactory.new,
+      },
+    )
+
+    template = Template.parse(
+      '{% render "snippet" %}',
+      line_numbers: true,
+    )
+    template.name = "template/index"
+
+    assert_equal(
+      "Liquid syntax error (some/path/snippet line 3): Variable '{{' was not properly terminated with regexp: /\\}\\}/",
+      template.render(context),
+    )
+  end
+
+  def test_error_is_raised_during_parse_with_template_name
+    depth = Liquid::Block::MAX_DEPTH + 1
+    code = "{% if true %}" * depth + "rendered" + "{% endif %}" * depth
+
+    template = Template.parse("{% render 'snippet' %}", line_numbers: true)
+
+    context = Liquid::Context.build(
+      registers: {
+        file_system: StubFileSystem.new("snippet" => code),
+        template_factory: StubTemplateFactory.new,
+      },
+    )
+
+    assert_equal("Liquid error (some/path/snippet line 1): Nesting too deep", template.render(context))
+  end
+
+  def test_internal_error_is_raised_with_template_name
+    template = Template.new
+    template.parse(
+      "{% render 'snippet' %}",
+      line_numbers: true,
+    )
+    template.name = "template/index"
+
+    context = Liquid::Context.build(
+      registers: {
+        file_system: StubFileSystem.new({}),
+      },
+    )
+
+    assert_equal(
+      "Liquid error (template/index line 1): internal",
+      template.render(context),
+    )
+  end
 end

test/integration/expression_test.rb

@@ -32,11 +32,11 @@ class ExpressionTest < Minitest::Test
 
     assert_match_syntax_error(
       "Liquid syntax error (line 1): Invalid expression type 'false' in range expression",
-      "{{ (false..true) }}"
+      "{{ (false..true) }}",
     )
     assert_match_syntax_error(
       "Liquid syntax error (line 1): Invalid expression type '(1..2)' in range expression",
-      "{{ ((1..2)..3) }}"
+      "{{ ((1..2)..3) }}",
     )
   end
 

test/integration/filter_kwarg_test.rb

@@ -17,7 +17,7 @@ class FilterKwargTest < Minitest::Test
     with_global_filter(KwargFilter) do
       assert_equal(
         "data-src='src' data-widths='100, 200'",
-        Template.parse("{{ 'img' | html_tag: data-src: 'src', data-widths: '100, 200' }}").render(nil, nil)
+        Template.parse("{{ 'img' | html_tag: data-src: 'src', data-widths: '100, 200' }}").render(nil, nil),
       )
     end
   end

test/integration/filter_test.rb

@@ -68,22 +68,34 @@ class FiltersTest < Minitest::Test
 
   def test_sort
     assert_template_result("1 2 3 4", "{{numbers | sort | join}}", { "numbers" => [2, 1, 4, 3] })
-    assert_template_result("alphabetic as expected", "{{words | sort | join}}",
-      { "words" => ['expected', 'as', 'alphabetic'] })
+    assert_template_result(
+      "alphabetic as expected",
+      "{{words | sort | join}}",
+      { "words" => ['expected', 'as', 'alphabetic'] },
+    )
     assert_template_result("3", "{{value | sort}}", { "value" => 3 })
     assert_template_result('are flower', "{{arrays | sort | join}}", { 'arrays' => ['flower', 'are'] })
-    assert_template_result("Expected case sensitive", "{{case_sensitive | sort | join}}",
-      { "case_sensitive" => ["sensitive", "Expected", "case"] })
+    assert_template_result(
+      "Expected case sensitive",
+      "{{case_sensitive | sort | join}}",
+      { "case_sensitive" => ["sensitive", "Expected", "case"] },
+    )
   end
 
   def test_sort_natural
     # Test strings
-    assert_template_result("Assert case Insensitive", "{{words | sort_natural | join}}",
-      { "words" => ["case", "Assert", "Insensitive"] })
+    assert_template_result(
+      "Assert case Insensitive",
+      "{{words | sort_natural | join}}",
+      { "words" => ["case", "Assert", "Insensitive"] },
+    )
 
     # Test hashes
-    assert_template_result("A b C", "{{hashes | sort_natural: 'a' | map: 'a' | join}}",
-      { "hashes" => [{ "a" => "A" }, { "a" => "b" }, { "a" => "C" }] })
+    assert_template_result(
+      "A b C",
+      "{{hashes | sort_natural: 'a' | map: 'a' | join}}",
+      { "hashes" => [{ "a" => "A" }, { "a" => "b" }, { "a" => "C" }] },
+    )
 
     # Test objects
     @context['objects'] = [TestObject.new('A'), TestObject.new('b'), TestObject.new('C')]
@@ -92,12 +104,18 @@ class FiltersTest < Minitest::Test
 
   def test_compact
     # Test strings
-    assert_template_result("a b c", "{{words | compact | join}}",
-      { "words" => ['a', nil, 'b', nil, 'c'] })
+    assert_template_result(
+      "a b c",
+      "{{words | compact | join}}",
+      { "words" => ['a', nil, 'b', nil, 'c'] },
+    )
 
     # Test hashes
-    assert_template_result("A C", "{{hashes | compact: 'a' | map: 'a' | join}}",
-      { "hashes" => [{ "a" => "A" }, { "a" => nil }, { "a" => "C" }] })
+    assert_template_result(
+      "A C",
+      "{{hashes | compact: 'a' | map: 'a' | join}}",
+      { "hashes" => [{ "a" => "A" }, { "a" => nil }, { "a" => "C" }] },
+    )
 
     # Test objects
     @context['objects'] = [TestObject.new('A'), TestObject.new(nil), TestObject.new('C')]
@@ -109,8 +127,11 @@ class FiltersTest < Minitest::Test
   end
 
   def test_strip_html_ignore_comments_with_html
-    assert_template_result("bla blub", "{{ var | strip_html }}",
-      { "var" => "<!-- split and some <ul> tag --><b>bla blub</a>" })
+    assert_template_result(
+      "bla blub",
+      "{{ var | strip_html }}",
+      { "var" => "<!-- split and some <ul> tag --><b>bla blub</a>" },
+    )
   end
 
   def test_capitalize

test/integration/parsing_quirks_test.rb

@@ -131,4 +131,16 @@ class ParsingQuirksTest < Minitest::Test
   def test_contains_in_id
     assert_template_result(' YES ', '{% if containsallshipments == true %} YES {% endif %}', { 'containsallshipments' => true })
   end
+
+  def test_incomplete_expression
+    with_error_mode(:lax) do
+      assert_template_result("false", "{% liquid assign foo = false -\n%}{{ foo }}")
+      assert_template_result("false", "{% liquid assign foo = false >\n%}{{ foo }}")
+      assert_template_result("false", "{% liquid assign foo = false <\n%}{{ foo }}")
+      assert_template_result("false", "{% liquid assign foo = false =\n%}{{ foo }}")
+      assert_template_result("false", "{% liquid assign foo = false !\n%}{{ foo }}")
+      assert_template_result("false", "{% liquid assign foo = false 1\n%}{{ foo }}")
+      assert_template_result("false", "{% liquid assign foo = false a\n%}{{ foo }}")
+    end
+  end
 end # ParsingQuirksTest

test/integration/profiler_test.rb

@@ -33,7 +33,7 @@ class ProfilerTest < Minitest::Test
   end
 
   def setup
-    Liquid::Template.file_system = ProfilingFileSystem.new
+    Liquid::Environment.default.file_system = ProfilingFileSystem.new
   end
 
   def test_template_allows_flagging_profiling

test/integration/standard_filter_test.rb

@@ -32,7 +32,7 @@ class TestDrop < Liquid::Drop
   attr_reader :value
 
   def registers
-    { @value => @context.registers[@value] }
+    "{#{@value.inspect}=>#{@context.registers[@value].inspect}}"
   end
 end
 
@@ -176,7 +176,17 @@ class StandardFiltersTest < Minitest::Test
   end
 
   def test_base64_decode
-    assert_equal('one two three', @filters.base64_decode('b25lIHR3byB0aHJlZQ=='))
+    decoded = @filters.base64_decode('b25lIHR3byB0aHJlZQ==')
+    assert_equal('one two three', decoded)
+    assert_equal(Encoding::UTF_8, decoded.encoding)
+
+    decoded = @filters.base64_decode('4pyF')
+    assert_equal('✅', decoded)
+    assert_equal(Encoding::UTF_8, decoded.encoding)
+
+    decoded = @filters.base64_decode("/w==")
+    assert_equal(Encoding::ASCII_8BIT, decoded.encoding)
+    assert_equal((+"\xFF").force_encoding(Encoding::ASCII_8BIT), decoded)
 
     exception = assert_raises(Liquid::ArgumentError) do
       @filters.base64_decode("invalidbase64")
@@ -188,16 +198,27 @@ class StandardFiltersTest < Minitest::Test
   def test_base64_url_safe_encode
     assert_equal(
       'YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXogQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVogMTIzNDU2Nzg5MCAhQCMkJV4mKigpLT1fKy8_Ljo7W117fVx8',
-      @filters.base64_url_safe_encode('abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 1234567890 !@#$%^&*()-=_+/?.:;[]{}\|')
+      @filters.base64_url_safe_encode('abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 1234567890 !@#$%^&*()-=_+/?.:;[]{}\|'),
     )
     assert_equal('', @filters.base64_url_safe_encode(nil))
   end
 
   def test_base64_url_safe_decode
+    decoded = @filters.base64_url_safe_decode('YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXogQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVogMTIzNDU2Nzg5MCAhQCMkJV4mKigpLT1fKy8_Ljo7W117fVx8')
     assert_equal(
       'abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 1234567890 !@#$%^&*()-=_+/?.:;[]{}\|',
-      @filters.base64_url_safe_decode('YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXogQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVogMTIzNDU2Nzg5MCAhQCMkJV4mKigpLT1fKy8_Ljo7W117fVx8')
+      decoded,
     )
+    assert_equal(Encoding::UTF_8, decoded.encoding)
+
+    decoded = @filters.base64_url_safe_decode('4pyF')
+    assert_equal('✅', decoded)
+    assert_equal(Encoding::UTF_8, decoded.encoding)
+
+    decoded = @filters.base64_url_safe_decode("_w==")
+    assert_equal(Encoding::ASCII_8BIT, decoded.encoding)
+    assert_equal((+"\xFF").force_encoding(Encoding::ASCII_8BIT), decoded)
+
     exception = assert_raises(Liquid::ArgumentError) do
       @filters.base64_url_safe_decode("invalidbase64")
     end
@@ -230,7 +251,7 @@ class StandardFiltersTest < Minitest::Test
     assert_equal('one two three', @filters.truncatewords('one two three'))
     assert_equal(
       'Two small (13&#8221; x 5.5&#8221; x 10&#8221; high) baskets fit inside one large basket (13&#8221;...',
-      @filters.truncatewords('Two small (13&#8221; x 5.5&#8221; x 10&#8221; high) baskets fit inside one large basket (13&#8221; x 16&#8221; x 10.5&#8221; high) with cover.', 15)
+      @filters.truncatewords('Two small (13&#8221; x 5.5&#8221; x 10&#8221; high) baskets fit inside one large basket (13&#8221; x 16&#8221; x 10.5&#8221; high) with cover.', 15),
     )
     assert_equal("测试测试测试测试", @filters.truncatewords('测试测试测试测试', 5))
     assert_equal('one two1', @filters.truncatewords("one two three", 2, 1))
@@ -310,8 +331,8 @@ class StandardFiltersTest < Minitest::Test
       { "price" => "1", "handle" => "gamma" },
       { "price" => 2, "handle" => "epsilon" },
       { "price" => "4", "handle" => "alpha" },
-      { "handle" => "delta" },
       { "handle" => "beta" },
+      { "handle" => "delta" },
     ]
     assert_equal(expectation, @filters.sort_natural(input, "price"))
   end
@@ -433,8 +454,11 @@ class StandardFiltersTest < Minitest::Test
 
   def test_map
     assert_equal([1, 2, 3, 4], @filters.map([{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }], 'a'))
-    assert_template_result('abc', "{{ ary | map:'foo' | map:'bar' }}",
-      { 'ary' => [{ 'foo' => { 'bar' => 'a' } }, { 'foo' => { 'bar' => 'b' } }, { 'foo' => { 'bar' => 'c' } }] })
+    assert_template_result(
+      'abc',
+      "{{ ary | map:'foo' | map:'bar' }}",
+      { 'ary' => [{ 'foo' => { 'bar' => 'a' } }, { 'foo' => { 'bar' => 'b' } }, { 'foo' => { 'bar' => 'c' } }] },
+    )
   end
 
   def test_map_doesnt_call_arbitrary_stuff
@@ -458,8 +482,11 @@ class StandardFiltersTest < Minitest::Test
   end
 
   def test_map_on_hashes
-    assert_template_result("4217", '{{ thing | map: "foo" | map: "bar" }}',
-      { "thing" => { "foo" => [{ "bar" => 42 }, { "bar" => 17 }] } })
+    assert_template_result(
+      "4217",
+      '{{ thing | map: "foo" | map: "bar" }}',
+      { "thing" => { "foo" => [{ "bar" => 42 }, { "bar" => 17 }] } },
+    )
   end
 
   def test_legacy_map_on_hashes_with_dynamic_key
@@ -922,6 +949,108 @@ class StandardFiltersTest < Minitest::Test
     assert_equal([{ "foo" => true }, { "foo" => "for sure" }], @filters.where(input, "foo"))
   end
 
+  def test_sum_with_all_numbers
+    input = [1, 2]
+
+    assert_equal(3, @filters.sum(input))
+    assert_raises(Liquid::ArgumentError, "cannot select the property 'quantity'") do
+      @filters.sum(input, "quantity")
+    end
+  end
+
+  def test_sum_with_numeric_strings
+    input = [1, 2, "3", "4"]
+
+    assert_equal(10, @filters.sum(input))
+    assert_raises(Liquid::ArgumentError, "cannot select the property 'quantity'") do
+      @filters.sum(input, "quantity")
+    end
+  end
+
+  def test_sum_with_nested_arrays
+    input = [1, [2, [3, 4]]]
+
+    assert_equal(10, @filters.sum(input))
+    assert_raises(Liquid::ArgumentError, "cannot select the property 'quantity'") do
+      @filters.sum(input, "quantity")
+    end
+  end
+
+  def test_sum_with_indexable_map_values
+    input = [{ "quantity" => 1 }, { "quantity" => 2, "weight" => 3 }, { "weight" => 4 }]
+
+    assert_equal(0, @filters.sum(input))
+    assert_equal(3, @filters.sum(input, "quantity"))
+    assert_equal(7, @filters.sum(input, "weight"))
+    assert_equal(0, @filters.sum(input, "subtotal"))
+  end
+
+  def test_sum_with_indexable_non_map_values
+    input = [1, [2], "foo", { "quantity" => 3 }]
+
+    assert_equal(3, @filters.sum(input))
+    assert_raises(Liquid::ArgumentError, "cannot select the property 'quantity'") do
+      @filters.sum(input, "quantity")
+    end
+  end
+
+  def test_sum_with_unindexable_values
+    input = [1, true, nil, { "quantity" => 2 }]
+
+    assert_equal(1, @filters.sum(input))
+    assert_raises(Liquid::ArgumentError, "cannot select the property 'quantity'") do
+      @filters.sum(input, "quantity")
+    end
+  end
+
+  def test_sum_without_property_calls_to_liquid
+    t = TestThing.new
+    Liquid::Template.parse('{{ foo | sum }}').render("foo" => [t])
+    assert(t.foo > 0)
+  end
+
+  def test_sum_with_property_calls_to_liquid_on_property_values
+    t = TestThing.new
+    Liquid::Template.parse('{{ foo | sum: "quantity" }}').render("foo" => [{ "quantity" => t }])
+    assert(t.foo > 0)
+  end
+
+  def test_sum_of_floats
+    input = [0.1, 0.2, 0.3]
+    assert_equal(0.6, @filters.sum(input))
+    assert_template_result("0.6", "{{ input | sum }}", { "input" => input })
+  end
+
+  def test_sum_of_negative_floats
+    input = [0.1, 0.2, -0.3]
+    assert_equal(0.0, @filters.sum(input))
+    assert_template_result("0.0", "{{ input | sum }}", { "input" => input })
+  end
+
+  def test_sum_with_float_strings
+    input = [0.1, "0.2", "0.3"]
+    assert_equal(0.6, @filters.sum(input))
+    assert_template_result("0.6", "{{ input | sum }}", { "input" => input })
+  end
+
+  def test_sum_resulting_in_negative_float
+    input = [0.1, -0.2, -0.3]
+    assert_equal(-0.4, @filters.sum(input))
+    assert_template_result("-0.4", "{{ input | sum }}", { "input" => input })
+  end
+
+  def test_sum_with_floats_and_indexable_map_values
+    input = [{ "quantity" => 1 }, { "quantity" => 0.2, "weight" => -0.3 }, { "weight" => 0.4 }]
+    assert_equal(0.0, @filters.sum(input))
+    assert_equal(1.2, @filters.sum(input, "quantity"))
+    assert_equal(0.1, @filters.sum(input, "weight"))
+    assert_equal(0.0, @filters.sum(input, "subtotal"))
+    assert_template_result("0", "{{ input | sum }}", { "input" => input })
+    assert_template_result("1.2", "{{ input | sum: 'quantity' }}", { "input" => input })
+    assert_template_result("0.1", "{{ input | sum: 'weight' }}", { "input" => input })
+    assert_template_result("0", "{{ input | sum: 'subtotal' }}", { "input" => input })
+  end
+
   private
 
   def with_timezone(tz)

test/integration/tags/for_tag_test.rb

@@ -73,9 +73,11 @@ HERE
 
   def test_for_helpers
     assigns = { 'array' => [1, 2, 3] }
-    assert_template_result(' 1/3  2/3  3/3 ',
+    assert_template_result(
+      ' 1/3  2/3  3/3 ',
       '{%for item in array%} {{forloop.index}}/{{forloop.length}} {%endfor%}',
-      assigns)
+      assigns,
+    )
     assert_template_result(' 1  2  3 ', '{%for item in array%} {{forloop.index}} {%endfor%}', assigns)
     assert_template_result(' 0  1  2 ', '{%for item in array%} {{forloop.index0}} {%endfor%}', assigns)
     assert_template_result(' 2  1  0 ', '{%for item in array%} {{forloop.rindex0}} {%endfor%}', assigns)
@@ -86,9 +88,11 @@ HERE
 
   def test_for_and_if
     assigns = { 'array' => [1, 2, 3] }
-    assert_template_result('+--',
+    assert_template_result(
+      '+--',
       '{%for item in array%}{% if forloop.first %}+{% else %}-{% endif %}{%endfor%}',
-      assigns)
+      assigns,
+    )
   end
 
   def test_for_else
@@ -103,6 +107,7 @@ HERE
     assert_template_result('1234', '{%for i in array limit:4 %}{{ i }}{%endfor%}', assigns)
     assert_template_result('3456', '{%for i in array limit:4 offset:2 %}{{ i }}{%endfor%}', assigns)
     assert_template_result('3456', '{%for i in array limit: 4 offset: 2 %}{{ i }}{%endfor%}', assigns)
+    assert_template_result('3456', '{%for i in array, limit: 4, offset: 2 %}{{ i }}{%endfor%}', assigns)
   end
 
   def test_limiting_with_invalid_limit
@@ -324,15 +329,20 @@ HERE
     # ruby 1.9.3 no longer supports .each on String though we mimic
     # the functionality for backwards compatibility
 
-    assert_template_result('test string',
+    assert_template_result(
+      'test string',
       '{%for val in string%}{{val}}{%endfor%}',
-      { 'string' => "test string" })
+      { 'string' => "test string" },
+    )
 
-    assert_template_result('test string',
+    assert_template_result(
+      'test string',
       '{%for val in string limit:1%}{{val}}{%endfor%}',
-      { 'string' => "test string" })
+      { 'string' => "test string" },
+    )
 
-    assert_template_result('val-string-1-1-0-1-0-true-true-test string',
+    assert_template_result(
+      'val-string-1-1-0-1-0-true-true-test string',
       '{%for val in string%}' \
       '{{forloop.name}}-' \
       '{{forloop.index}}-' \
@@ -343,23 +353,28 @@ HERE
       '{{forloop.first}}-' \
       '{{forloop.last}}-' \
       '{{val}}{%endfor%}',
-      { 'string' => "test string" })
+      { 'string' => "test string" },
+    )
   end
 
   def test_for_parentloop_references_parent_loop
-    assert_template_result('1.1 1.2 1.3 2.1 2.2 2.3 ',
+    assert_template_result(
+      '1.1 1.2 1.3 2.1 2.2 2.3 ',
       '{% for inner in outer %}{% for k in inner %}' \
       '{{ forloop.parentloop.index }}.{{ forloop.index }} ' \
       '{% endfor %}{% endfor %}',
-      { 'outer' => [[1, 1, 1], [1, 1, 1]] })
+      { 'outer' => [[1, 1, 1], [1, 1, 1]] },
+    )
   end
 
   def test_for_parentloop_nil_when_not_present
-    assert_template_result('.1 .2 ',
+    assert_template_result(
+      '.1 .2 ',
       '{% for inner in outer %}' \
       '{{ forloop.parentloop.index }}.{{ forloop.index }} ' \
       '{% endfor %}',
-      { 'outer' => [[1, 1, 1], [1, 1, 1]] })
+      { 'outer' => [[1, 1, 1], [1, 1, 1]] },
+    )
   end
 
   def test_inner_for_over_empty_input

test/integration/tags/if_else_tag_test.rb

@@ -7,8 +7,10 @@ class IfElseTagTest < Minitest::Test
 
   def test_if
     assert_template_result('  ', ' {% if false %} this text should not go into the output {% endif %} ')
-    assert_template_result('  this text should go into the output  ',
-      ' {% if true %} this text should go into the output {% endif %} ')
+    assert_template_result(
+      '  this text should go into the output  ',
+      ' {% if true %} this text should go into the output {% endif %} ',
+    )
     assert_template_result('  you rock ?', '{% if false %} you suck {% endif %} {% if true %} you rock {% endif %}?')
   end
 
@@ -51,18 +53,22 @@ class IfElseTagTest < Minitest::Test
 
   def test_comparison_of_expressions_starting_with_and_or_or
     assigns = { 'order' => { 'items_count' => 0 }, 'android' => { 'name' => 'Roy' } }
-    assert_template_result("YES",
+    assert_template_result(
+      "YES",
       "{% if android.name == 'Roy' %}YES{% endif %}",
-      assigns)
-    assert_template_result("YES",
+      assigns,
+    )
+    assert_template_result(
+      "YES",
       "{% if order.items_count == 0 %}YES{% endif %}",
-      assigns)
+      assigns,
+    )
   end
 
   def test_if_and
     assert_template_result(' YES ', '{% if true and true %} YES {% endif %}')
     assert_template_result('', '{% if false and true %} YES {% endif %}')
-    assert_template_result('', '{% if false and true %} YES {% endif %}')
+    assert_template_result('', '{% if true and false %} YES {% endif %}')
   end
 
   def test_hash_miss_generates_false
@@ -155,8 +161,10 @@ class IfElseTagTest < Minitest::Test
     original_op = Condition.operators['contains']
     Condition.operators['contains'] = :[]
 
-    assert_template_result('yes',
-      %({% if 'gnomeslab-and-or-liquid' contains 'gnomeslab-and-or-liquid' %}yes{% endif %}))
+    assert_template_result(
+      'yes',
+      %({% if 'gnomeslab-and-or-liquid' contains 'gnomeslab-and-or-liquid' %}yes{% endif %}),
+    )
   ensure
     Condition.operators['contains'] = original_op
   end

test/integration/tags/include_tag_test.rb

@@ -49,74 +49,89 @@ end
 class IncludeTagTest < Minitest::Test
   include Liquid
 
-  def setup
-    @default_file_system = Liquid::Template.file_system
-  end
-
-  def teardown
-    Liquid::Template.file_system = @default_file_system
-  end
-
   def test_include_tag_looks_for_file_system_in_registers_first
-    assert_equal('from OtherFileSystem',
-      Template.parse("{% include 'pick_a_source' %}").render!({}, registers: { file_system: OtherFileSystem.new }))
+    assert_equal(
+      'from OtherFileSystem',
+      Template.parse("{% include 'pick_a_source' %}").render!({}, registers: { file_system: OtherFileSystem.new }),
+    )
   end
 
   def test_include_tag_with
-    assert_template_result("Product: Draft 151cm ",
+    assert_template_result(
+      "Product: Draft 151cm ",
       "{% include 'product' with products[0] %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
-      partials: { "product" => "Product: {{ product.title }} " })
+      partials: { "product" => "Product: {{ product.title }} " },
+    )
   end
 
   def test_include_tag_with_alias
-    assert_template_result("Product: Draft 151cm ",
+    assert_template_result(
+      "Product: Draft 151cm ",
       "{% include 'product_alias' with products[0] as product %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
-      partials: { "product_alias" => "Product: {{ product.title }} " })
+      partials: { "product_alias" => "Product: {{ product.title }} " },
+    )
   end
 
   def test_include_tag_for_alias
-    assert_template_result("Product: Draft 151cm Product: Element 155cm ",
+    assert_template_result(
+      "Product: Draft 151cm Product: Element 155cm ",
       "{% include 'product_alias' for products as product %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
-      partials: { "product_alias" => "Product: {{ product.title }} " })
+      partials: { "product_alias" => "Product: {{ product.title }} " },
+    )
   end
 
   def test_include_tag_with_default_name
-    assert_template_result("Product: Draft 151cm ",
-      "{% include 'product' %}", { "product" => { 'title' => 'Draft 151cm' } },
-      partials: { "product" => "Product: {{ product.title }} " })
+    assert_template_result(
+      "Product: Draft 151cm ",
+      "{% include 'product' %}",
+      { "product" => { 'title' => 'Draft 151cm' } },
+      partials: { "product" => "Product: {{ product.title }} " },
+    )
   end
 
   def test_include_tag_for
-    assert_template_result("Product: Draft 151cm Product: Element 155cm ",
+    assert_template_result(
+      "Product: Draft 151cm Product: Element 155cm ",
       "{% include 'product' for products %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
-      partials: { "product" => "Product: {{ product.title }} " })
+      partials: { "product" => "Product: {{ product.title }} " },
+    )
   end
 
   def test_include_tag_with_local_variables
-    assert_template_result("Locale: test123 ", "{% include 'locale_variables' echo1: 'test123' %}",
-      partials: { "locale_variables" => "Locale: {{echo1}} {{echo2}}" })
+    assert_template_result(
+      "Locale: test123 ",
+      "{% include 'locale_variables' echo1: 'test123' %}",
+      partials: { "locale_variables" => "Locale: {{echo1}} {{echo2}}" },
+    )
   end
 
   def test_include_tag_with_multiple_local_variables
-    assert_template_result("Locale: test123 test321",
+    assert_template_result(
+      "Locale: test123 test321",
       "{% include 'locale_variables' echo1: 'test123', echo2: 'test321' %}",
-      partials: { "locale_variables" => "Locale: {{echo1}} {{echo2}}" })
+      partials: { "locale_variables" => "Locale: {{echo1}} {{echo2}}" },
+    )
   end
 
   def test_include_tag_with_multiple_local_variables_from_context
-    assert_template_result("Locale: test123 test321",
+    assert_template_result(
+      "Locale: test123 test321",
       "{% include 'locale_variables' echo1: echo1, echo2: more_echos.echo2 %}",
       { 'echo1' => 'test123', 'more_echos' => { "echo2" => 'test321' } },
-      partials: { "locale_variables" => "Locale: {{echo1}} {{echo2}}" })
+      partials: { "locale_variables" => "Locale: {{echo1}} {{echo2}}" },
+    )
   end
 
   def test_included_templates_assigns_variables
-    assert_template_result("bar", "{% include 'assignments' %}{{ foo }}",
-      partials: { 'assignments' => "{% assign foo = 'bar' %}" })
+    assert_template_result(
+      "bar",
+      "{% include 'assignments' %}{{ foo }}",
+      partials: { 'assignments' => "{% assign foo = 'bar' %}" },
+    )
   end
 
   def test_nested_include_tag
@@ -137,13 +152,19 @@ class IncludeTagTest < Minitest::Test
       "details" => "details",
     }
 
-    assert_template_result("Product: Draft 151cm details ",
-      "{% include 'nested_product_template' with product %}", { "product" => { "title" => 'Draft 151cm' } },
-      partials: partials)
+    assert_template_result(
+      "Product: Draft 151cm details ",
+      "{% include 'nested_product_template' with product %}",
+      { "product" => { "title" => 'Draft 151cm' } },
+      partials: partials,
+    )
 
-    assert_template_result("Product: Draft 151cm details Product: Element 155cm details ",
-      "{% include 'nested_product_template' for products %}", { "products" => [{ "title" => 'Draft 151cm' }, { "title" => 'Element 155cm' }] },
-      partials: partials)
+    assert_template_result(
+      "Product: Draft 151cm details Product: Element 155cm details ",
+      "{% include 'nested_product_template' for products %}",
+      { "products" => [{ "title" => 'Draft 151cm' }, { "title" => 'Element 155cm' }] },
+      partials: partials,
+    )
   end
 
   def test_recursively_included_template_does_not_produce_endless_loop
@@ -153,54 +174,77 @@ class IncludeTagTest < Minitest::Test
       end
     end
 
-    Liquid::Template.file_system = infinite_file_system.new
+    env = Liquid::Environment.build(file_system: infinite_file_system.new)
 
     assert_raises(Liquid::StackLevelError) do
-      Template.parse("{% include 'loop' %}").render!
+      Template.parse("{% include 'loop' %}", environment: env).render!
     end
   end
 
   def test_dynamically_choosen_template
-    assert_template_result("Test123", "{% include template %}", { "template" => 'Test123' },
-      partials: { "Test123" => "Test123" })
+    assert_template_result(
+      "Test123",
+      "{% include template %}",
+      { "template" => 'Test123' },
+      partials: { "Test123" => "Test123" },
+    )
 
-    assert_template_result("Test321", "{% include template %}", { "template" => 'Test321' },
-      partials: { "Test321" => "Test321" })
+    assert_template_result(
+      "Test321",
+      "{% include template %}",
+      { "template" => 'Test321' },
+      partials: { "Test321" => "Test321" },
+    )
 
-    assert_template_result("Product: Draft 151cm ", "{% include template for product %}",
+    assert_template_result(
+      "Product: Draft 151cm ",
+      "{% include template for product %}",
       { "template" => 'product', 'product' => { 'title' => 'Draft 151cm' } },
-      partials: { "product" => "Product: {{ product.title }} " })
+      partials: { "product" => "Product: {{ product.title }} " },
+    )
   end
 
   def test_include_tag_caches_second_read_of_same_partial
     file_system = CountingFileSystem.new
-    assert_equal('from CountingFileSystemfrom CountingFileSystem',
-      Template.parse("{% include 'pick_a_source' %}{% include 'pick_a_source' %}").render!({}, registers: { file_system: file_system }))
+    environment = Liquid::Environment.build(file_system: file_system)
+    assert_equal(
+      'from CountingFileSystemfrom CountingFileSystem',
+      Template.parse("{% include 'pick_a_source' %}{% include 'pick_a_source' %}", environment: environment).render!({}, registers: { file_system: file_system }),
+    )
     assert_equal(1, file_system.count)
   end
 
   def test_include_tag_doesnt_cache_partials_across_renders
     file_system = CountingFileSystem.new
-    assert_equal('from CountingFileSystem',
-      Template.parse("{% include 'pick_a_source' %}").render!({}, registers: { file_system: file_system }))
+    assert_equal(
+      'from CountingFileSystem',
+      Template.parse("{% include 'pick_a_source' %}").render!({}, registers: { file_system: file_system }),
+    )
     assert_equal(1, file_system.count)
 
-    assert_equal('from CountingFileSystem',
-      Template.parse("{% include 'pick_a_source' %}").render!({}, registers: { file_system: file_system }))
+    assert_equal(
+      'from CountingFileSystem',
+      Template.parse("{% include 'pick_a_source' %}").render!({}, registers: { file_system: file_system }),
+    )
     assert_equal(2, file_system.count)
   end
 
   def test_include_tag_within_if_statement
-    assert_template_result("foo_if_true", "{% if true %}{% include 'foo_if_true' %}{% endif %}",
-      partials: { "foo_if_true" => "foo_if_true" })
+    assert_template_result(
+      "foo_if_true",
+      "{% if true %}{% include 'foo_if_true' %}{% endif %}",
+      partials: { "foo_if_true" => "foo_if_true" },
+    )
   end
 
   def test_custom_include_tag
     original_tag = Liquid::Template.tags['include']
     Liquid::Template.tags['include'] = CustomInclude
     begin
-      assert_equal("custom_foo",
-        Template.parse("{% include 'custom_foo' %}").render!)
+      assert_equal(
+        "custom_foo",
+        Template.parse("{% include 'custom_foo' %}").render!,
+      )
     ensure
       Liquid::Template.tags['include'] = original_tag
     end
@@ -210,68 +254,92 @@ class IncludeTagTest < Minitest::Test
     original_tag = Liquid::Template.tags['include']
     Liquid::Template.tags['include'] = CustomInclude
     begin
-      assert_equal("custom_foo_if_true",
-        Template.parse("{% if true %}{% include 'custom_foo_if_true' %}{% endif %}").render!)
+      assert_equal(
+        "custom_foo_if_true",
+        Template.parse("{% if true %}{% include 'custom_foo_if_true' %}{% endif %}").render!,
+      )
     ensure
       Liquid::Template.tags['include'] = original_tag
     end
   end
 
   def test_does_not_add_error_in_strict_mode_for_missing_variable
-    Liquid::Template.file_system = TestFileSystem.new
+    env = Liquid::Environment.build(file_system: TestFileSystem.new)
 
-    a = Liquid::Template.parse(' {% include "nested_template" %}')
+    a = Liquid::Template.parse(' {% include "nested_template" %}', environment: env)
     a.render!
     assert_empty(a.errors)
   end
 
   def test_passing_options_to_included_templates
-    Liquid::Template.file_system = TestFileSystem.new
+    env = Liquid::Environment.build(file_system: TestFileSystem.new)
+
     assert_raises(Liquid::SyntaxError) do
-      Template.parse("{% include template %}", error_mode: :strict).render!("template" => '{{ "X" || downcase }}')
+      Template.parse("{% include template %}", error_mode: :strict, environment: env).render!("template" => '{{ "X" || downcase }}')
     end
     with_error_mode(:lax) do
-      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: true).render!("template" => '{{ "X" || downcase }}'))
+      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: true, environment: env).render!("template" => '{{ "X" || downcase }}'))
     end
     assert_raises(Liquid::SyntaxError) do
-      Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:locale]).render!("template" => '{{ "X" || downcase }}')
+      Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:locale], environment: env).render!("template" => '{{ "X" || downcase }}')
     end
     with_error_mode(:lax) do
-      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:error_mode]).render!("template" => '{{ "X" || downcase }}'))
+      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:error_mode], environment: env).render!("template" => '{{ "X" || downcase }}'))
     end
   end
 
   def test_render_raise_argument_error_when_template_is_undefined
-    assert_template_result("Liquid error (line 1): Argument error in tag 'include' - Illegal template name",
-      "{% include undefined_variable %}", render_errors: true)
+    assert_template_result(
+      "Liquid error (line 1): Argument error in tag 'include' - Illegal template name",
+      "{% include undefined_variable %}",
+      render_errors: true,
+    )
 
-    assert_template_result("Liquid error (line 1): Argument error in tag 'include' - Illegal template name",
-      "{% include nil %}", render_errors: true)
+    assert_template_result(
+      "Liquid error (line 1): Argument error in tag 'include' - Illegal template name",
+      "{% include nil %}",
+      render_errors: true,
+    )
   end
 
   def test_render_raise_argument_error_when_template_is_not_a_string
-    assert_template_result("Liquid error (line 1): Argument error in tag 'include' - Illegal template name",
-      "{% include 123 %}", render_errors: true)
+    assert_template_result(
+      "Liquid error (line 1): Argument error in tag 'include' - Illegal template name",
+      "{% include 123 %}",
+      render_errors: true,
+    )
   end
 
   def test_including_via_variable_value
-    assert_template_result("from TestFileSystem", "{% assign page = 'pick_a_source' %}{% include page %}",
-      partials: { "pick_a_source" => "from TestFileSystem" })
+    assert_template_result(
+      "from TestFileSystem",
+      "{% assign page = 'pick_a_source' %}{% include page %}",
+      partials: { "pick_a_source" => "from TestFileSystem" },
+    )
 
     partials = { "product" => "Product: {{ product.title }} " }
 
-    assert_template_result("Product: Draft 151cm ", "{% assign page = 'product' %}{% include page %}",
+    assert_template_result(
+      "Product: Draft 151cm ",
+      "{% assign page = 'product' %}{% include page %}",
       { "product" => { 'title' => 'Draft 151cm' } },
-      partials: partials)
+      partials: partials,
+    )
 
-    assert_template_result("Product: Draft 151cm ", "{% assign page = 'product' %}{% include page for foo %}",
+    assert_template_result(
+      "Product: Draft 151cm ",
+      "{% assign page = 'product' %}{% include page for foo %}",
       { "foo" => { 'title' => 'Draft 151cm' } },
-      partials: partials)
+      partials: partials,
+    )
   end
 
   def test_including_with_strict_variables
-    Liquid::Template.file_system = StubFileSystem.new({ "simple" => "simple" })
-    template = Liquid::Template.parse("{% include 'simple' %}", error_mode: :warn)
+    env = Liquid::Environment.build(
+      file_system: StubFileSystem.new('simple' => 'simple'),
+    )
+
+    template = Liquid::Template.parse("{% include 'simple' %}", error_mode: :warn, environment: env)
     template.render(nil, strict_variables: true)
 
     assert_equal([], template.errors)
@@ -279,7 +347,31 @@ class IncludeTagTest < Minitest::Test
 
   def test_break_through_include
     assert_template_result("1", "{% for i in (1..3) %}{{ i }}{% break %}{{ i }}{% endfor %}")
-    assert_template_result("1", "{% for i in (1..3) %}{{ i }}{% include 'break' %}{{ i }}{% endfor %}",
-      partials: { 'break' => "{% break %}" })
+    assert_template_result(
+      "1",
+      "{% for i in (1..3) %}{{ i }}{% include 'break' %}{{ i }}{% endfor %}",
+      partials: { 'break' => "{% break %}" },
+    )
+  end
+
+  def test_render_tag_renders_error_with_template_name
+    assert_template_result(
+      'Liquid error (foo line 1): standard error',
+      "{% include 'foo' with errors %}",
+      { 'errors' => ErrorDrop.new },
+      partials: { 'foo' => '{{ foo.standard_error }}' },
+      render_errors: true,
+    )
+  end
+
+  def test_render_tag_renders_error_with_template_name_from_template_factory
+    assert_template_result(
+      'Liquid error (some/path/foo line 1): standard error',
+      "{% include 'foo' with errors %}",
+      { 'errors' => ErrorDrop.new },
+      partials: { 'foo' => '{{ foo.standard_error }}' },
+      template_factory: StubTemplateFactory.new,
+      render_errors: true,
+    )
   end
 end # IncludeTagTest

test/integration/tags/increment_tag_test.rb

@@ -8,19 +8,23 @@ class IncrementTagTest < Minitest::Test
   def test_inc
     assert_template_result('0 1', '{%increment port %} {{ port }}')
     assert_template_result(' 0 1 2', '{{port}} {%increment port %} {%increment port%} {{port}}')
-    assert_template_result('0 0 1 2 1',
+    assert_template_result(
+      '0 0 1 2 1',
       '{%increment port %} {%increment starboard%} ' \
       '{%increment port %} {%increment port%} ' \
-      '{%increment starboard %}')
+      '{%increment starboard %}',
+    )
   end
 
   def test_dec
     assert_template_result('-1 -1', '{%decrement port %} {{ port }}', { 'port' => 10 })
     assert_template_result(' -1 -2 -2', '{{port}} {%decrement port %} {%decrement port%} {{port}}')
-    assert_template_result('0 1 2 0 3 1 1 3',
+    assert_template_result(
+      '0 1 2 0 3 1 1 3',
       '{%increment starboard %} {%increment starboard%} {%increment starboard%} ' \
       '{%increment port %} {%increment starboard%} ' \
       '{%increment port %} {%decrement port%} ' \
-      '{%decrement starboard %}')
+      '{%decrement starboard %}',
+    )
   end
 end

test/integration/tags/liquid_tag_test.rb

@@ -113,4 +113,37 @@ class LiquidTagTest < Minitest::Test
       {% raw %}{% liquid echo 'test' %}{% endraw %}
     LIQUID
   end
+
+  def test_nested_liquid_tags
+    assert_template_result('good', <<~LIQUID)
+      {%- liquid
+        liquid
+          if true
+            echo "good"
+          endif
+      -%}
+    LIQUID
+  end
+
+  def test_nested_liquid_tags_on_same_line
+    assert_template_result('good', <<~LIQUID)
+      {%- liquid liquid liquid echo "good" -%}
+    LIQUID
+  end
+
+  def test_nested_liquid_liquid_is_not_skipped_if_used_in_non_tag_position
+    assert_template_result('liquid', <<~LIQUID, { 'liquid' => 'liquid' })
+      {%- liquid liquid liquid echo liquid -%}
+    LIQUID
+  end
+
+  def test_next_liquid_with_unclosed_if_tag
+    assert_match_syntax_error("Liquid syntax error (line 2): 'if' tag was never closed", <<~LIQUID)
+      {%- liquid
+        liquid if true
+          echo "good"
+        endif
+      -%}
+    LIQUID
+  end
 end

test/integration/tags/raw_tag_test.rb

@@ -6,12 +6,16 @@ class RawTagTest < Minitest::Test
   include Liquid
 
   def test_tag_in_raw
-    assert_template_result('{% comment %} test {% endcomment %}',
-      '{% raw %}{% comment %} test {% endcomment %}{% endraw %}')
+    assert_template_result(
+      '{% comment %} test {% endcomment %}',
+      '{% raw %}{% comment %} test {% endcomment %}{% endraw %}',
+    )
   end
 
   def test_output_in_raw
-    assert_template_result('{{ test }}', '{% raw %}{{ test }}{% endraw %}')
+    assert_template_result('>{{ test }}<', '> {%- raw -%}{{ test }}{%- endraw -%} <')
+    assert_template_result("> inner  <", "> {%- raw -%} inner {%- endraw %} <")
+    assert_template_result("> inner <", "> {%- raw -%} inner {%- endraw -%} <")
   end
 
   def test_open_tag_in_raw

test/integration/tags/render_tag_test.rb

@@ -6,68 +6,98 @@ class RenderTagTest < Minitest::Test
   include Liquid
 
   def test_render_with_no_arguments
-    assert_template_result('rendered content', '{% render "source" %}',
-      partials: { 'source' => 'rendered content' })
+    assert_template_result(
+      'rendered content',
+      '{% render "source" %}',
+      partials: { 'source' => 'rendered content' },
+    )
   end
 
   def test_render_tag_looks_for_file_system_in_registers_first
-    assert_template_result('from register file system', '{% render "pick_a_source" %}',
-      partials: { 'pick_a_source' => 'from register file system' })
+    assert_template_result(
+      'from register file system',
+      '{% render "pick_a_source" %}',
+      partials: { 'pick_a_source' => 'from register file system' },
+    )
   end
 
   def test_render_passes_named_arguments_into_inner_scope
-    assert_template_result('My Product', '{% render "product", inner_product: outer_product %}',
+    assert_template_result(
+      'My Product',
+      '{% render "product", inner_product: outer_product %}',
       { 'outer_product' => { 'title' => 'My Product' } },
-      partials: { 'product' => '{{ inner_product.title }}' })
+      partials: { 'product' => '{{ inner_product.title }}' },
+    )
   end
 
   def test_render_accepts_literals_as_arguments
-    assert_template_result('123', '{% render "snippet", price: 123 %}',
-      partials: { 'snippet' => '{{ price }}' })
+    assert_template_result(
+      '123',
+      '{% render "snippet", price: 123 %}',
+      partials: { 'snippet' => '{{ price }}' },
+    )
   end
 
   def test_render_accepts_multiple_named_arguments
-    assert_template_result('1 2', '{% render "snippet", one: 1, two: 2 %}',
-      partials: { 'snippet' => '{{ one }} {{ two }}' })
+    assert_template_result(
+      '1 2',
+      '{% render "snippet", one: 1, two: 2 %}',
+      partials: { 'snippet' => '{{ one }} {{ two }}' },
+    )
   end
 
   def test_render_does_not_inherit_parent_scope_variables
-    assert_template_result('', '{% assign outer_variable = "should not be visible" %}{% render "snippet" %}',
-      partials: { 'snippet' => '{{ outer_variable }}' })
+    assert_template_result(
+      '',
+      '{% assign outer_variable = "should not be visible" %}{% render "snippet" %}',
+      partials: { 'snippet' => '{{ outer_variable }}' },
+    )
   end
 
   def test_render_does_not_inherit_variable_with_same_name_as_snippet
-    assert_template_result('', "{% assign snippet = 'should not be visible' %}{% render 'snippet' %}",
-      partials: { 'snippet' => '{{ snippet }}' })
+    assert_template_result(
+      '',
+      "{% assign snippet = 'should not be visible' %}{% render 'snippet' %}",
+      partials: { 'snippet' => '{{ snippet }}' },
+    )
   end
 
   def test_render_does_not_mutate_parent_scope
-    assert_template_result('', "{% render 'snippet' %}{{ inner }}",
-      partials: { 'snippet' => '{% assign inner = 1 %}' })
+    assert_template_result(
+      '',
+      "{% render 'snippet' %}{{ inner }}",
+      partials: { 'snippet' => '{% assign inner = 1 %}' },
+    )
   end
 
   def test_nested_render_tag
-    assert_template_result('one two', "{% render 'one' %}",
+    assert_template_result(
+      'one two',
+      "{% render 'one' %}",
       partials: {
         'one' => "one {% render 'two' %}",
         'two' => 'two',
-      })
+      },
+    )
   end
 
   def test_recursively_rendered_template_does_not_produce_endless_loop
-    Liquid::Template.file_system = StubFileSystem.new('loop' => '{% render "loop" %}')
+    env = Liquid::Environment.build(
+      file_system: StubFileSystem.new('loop' => '{% render "loop" %}'),
+    )
 
     assert_raises(Liquid::StackLevelError) do
-      Template.parse('{% render "loop" %}').render!
+      Template.parse('{% render "loop" %}', environment: env).render!
     end
   end
 
   def test_sub_contexts_count_towards_the_same_recursion_limit
-    Liquid::Template.file_system = StubFileSystem.new(
-      'loop_render' => '{% render "loop_render" %}',
+    env = Liquid::Environment.build(
+      file_system: StubFileSystem.new('loop_render' => '{% render "loop_render" %}'),
     )
+
     assert_raises(Liquid::StackLevelError) do
-      Template.parse('{% render "loop_render" %}').render!
+      Template.parse('{% render "loop_render" %}', environment: env).render!
     end
   end
 
@@ -77,27 +107,36 @@ class RenderTagTest < Minitest::Test
 
   def test_include_tag_caches_second_read_of_same_partial
     file_system = StubFileSystem.new('snippet' => 'echo')
-    assert_equal('echoecho',
+    assert_equal(
+      'echoecho',
       Template.parse('{% render "snippet" %}{% render "snippet" %}')
-      .render!({}, registers: { file_system: file_system }))
+      .render!({}, registers: { file_system: file_system }),
+    )
     assert_equal(1, file_system.file_read_count)
   end
 
   def test_render_tag_doesnt_cache_partials_across_renders
     file_system = StubFileSystem.new('snippet' => 'my message')
 
-    assert_equal('my message',
-      Template.parse('{% include "snippet" %}').render!({}, registers: { file_system: file_system }))
+    assert_equal(
+      'my message',
+      Template.parse('{% include "snippet" %}').render!({}, registers: { file_system: file_system }),
+    )
     assert_equal(1, file_system.file_read_count)
 
-    assert_equal('my message',
-      Template.parse('{% include "snippet" %}').render!({}, registers: { file_system: file_system }))
+    assert_equal(
+      'my message',
+      Template.parse('{% include "snippet" %}').render!({}, registers: { file_system: file_system }),
+    )
     assert_equal(2, file_system.file_read_count)
   end
 
   def test_render_tag_within_if_statement
-    assert_template_result('my message', '{% if true %}{% render "snippet" %}{% endif %}',
-      partials: { 'snippet' => 'my message' })
+    assert_template_result(
+      'my message',
+      '{% if true %}{% render "snippet" %}{% endif %}',
+      partials: { 'snippet' => 'my message' },
+    )
   end
 
   def test_break_through_render
@@ -107,13 +146,19 @@ class RenderTagTest < Minitest::Test
   end
 
   def test_increment_is_isolated_between_renders
-    assert_template_result('010', '{% increment %}{% increment %}{% render "incr" %}',
-      partials: { 'incr' => '{% increment %}' })
+    assert_template_result(
+      '010',
+      '{% increment %}{% increment %}{% render "incr" %}',
+      partials: { 'incr' => '{% increment %}' },
+    )
   end
 
   def test_decrement_is_isolated_between_renders
-    assert_template_result('-1-2-1', '{% decrement %}{% decrement %}{% render "decr" %}',
-      partials: { 'decr' => '{% decrement %}' })
+    assert_template_result(
+      '-1-2-1',
+      '{% decrement %}{% decrement %}{% render "decr" %}',
+      partials: { 'decr' => '{% decrement %}' },
+    )
   end
 
   def test_includes_will_not_render_inside_render_tag
@@ -124,7 +169,7 @@ class RenderTagTest < Minitest::Test
       partials: {
         'foo' => 'bar',
         'test_include' => '{% include "foo" %}',
-      }
+      },
     )
   end
 
@@ -138,72 +183,109 @@ class RenderTagTest < Minitest::Test
         'nested_render_with_sibling_include' => '{% render "test_include" %}{% include "foo" %}',
         'test_include' => '{% include "foo" %}',
       },
-      render_errors: true
+      render_errors: true,
     )
   end
 
   def test_render_tag_with
-    assert_template_result("Product: Draft 151cm ",
+    assert_template_result(
+      "Product: Draft 151cm ",
       "{% render 'product' with products[0] %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
       partials: {
         'product' => "Product: {{ product.title }} ",
         'product_alias' => "Product: {{ product.title }} ",
-      })
+      },
+    )
   end
 
   def test_render_tag_with_alias
-    assert_template_result("Product: Draft 151cm ",
+    assert_template_result(
+      "Product: Draft 151cm ",
       "{% render 'product_alias' with products[0] as product %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
       partials: {
         'product' => "Product: {{ product.title }} ",
         'product_alias' => "Product: {{ product.title }} ",
-      })
+      },
+    )
   end
 
   def test_render_tag_for_alias
-    assert_template_result("Product: Draft 151cm Product: Element 155cm ",
+    assert_template_result(
+      "Product: Draft 151cm Product: Element 155cm ",
       "{% render 'product_alias' for products as product %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
       partials: {
         'product' => "Product: {{ product.title }} ",
         'product_alias' => "Product: {{ product.title }} ",
-      })
+      },
+    )
   end
 
   def test_render_tag_for
-    assert_template_result("Product: Draft 151cm Product: Element 155cm ",
+    assert_template_result(
+      "Product: Draft 151cm Product: Element 155cm ",
       "{% render 'product' for products %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
       partials: {
         'product' => "Product: {{ product.title }} ",
         'product_alias' => "Product: {{ product.title }} ",
-      })
+      },
+    )
   end
 
   def test_render_tag_forloop
-    assert_template_result("Product: Draft 151cm first  index:1 Product: Element 155cm  last index:2 ",
+    assert_template_result(
+      "Product: Draft 151cm first  index:1 Product: Element 155cm  last index:2 ",
       "{% render 'product' for products %}",
       { "products" => [{ 'title' => 'Draft 151cm' }, { 'title' => 'Element 155cm' }] },
       partials: {
         'product' => "Product: {{ product.title }} {% if forloop.first %}first{% endif %} {% if forloop.last %}last{% endif %} index:{{ forloop.index }} ",
-      })
+      },
+    )
   end
 
   def test_render_tag_for_drop
-    assert_template_result("123",
-      "{% render 'loop' for loop as value %}", { "loop" => TestEnumerable.new },
+    assert_template_result(
+      "123",
+      "{% render 'loop' for loop as value %}",
+      { "loop" => TestEnumerable.new },
       partials: {
         'loop' => "{{ value.foo }}",
-      })
+      },
+    )
   end
 
   def test_render_tag_with_drop
-    assert_template_result("TestEnumerable",
-      "{% render 'loop' with loop as value %}", { "loop" => TestEnumerable.new },
+    assert_template_result(
+      "TestEnumerable",
+      "{% render 'loop' with loop as value %}",
+      { "loop" => TestEnumerable.new },
       partials: {
         'loop' => "{{ value }}",
-      })
+      },
+    )
+  end
+
+  def test_render_tag_renders_error_with_template_name
+    assert_template_result(
+      'Liquid error (foo line 1): standard error',
+      "{% render 'foo' with errors %}",
+      { 'errors' => ErrorDrop.new },
+      partials: { 'foo' => '{{ foo.standard_error }}' },
+      render_errors: true,
+    )
+  end
+
+  def test_render_tag_renders_error_with_template_name_from_template_factory
+    assert_template_result(
+      'Liquid error (some/path/foo line 1): standard error',
+      "{% render 'foo' with errors %}",
+      { 'errors' => ErrorDrop.new },
+      partials: { 'foo' => '{{ foo.standard_error }}' },
+      template_factory: StubTemplateFactory.new,
+      render_errors: true,
+    )
   end
 end

test/integration/tags/standard_tag_test.rb

@@ -6,8 +6,10 @@ class StandardTagTest < Minitest::Test
   include Liquid
 
   def test_no_transform
-    assert_template_result('this text should come out of the template without change...',
-      'this text should come out of the template without change...')
+    assert_template_result(
+      'this text should come out of the template without change...',
+      'this text should come out of the template without change...',
+    )
 
     assert_template_result('blah', 'blah')
     assert_template_result('<blah>', '<blah>')
@@ -20,8 +22,10 @@ class StandardTagTest < Minitest::Test
   end
 
   def test_has_a_block_which_does_nothing
-    assert_template_result(%(the comment block should be removed  .. right?),
-      %(the comment block should be removed {%comment%} be gone.. {%endcomment%} .. right?))
+    assert_template_result(
+      %(the comment block should be removed  .. right?),
+      %(the comment block should be removed {%comment%} be gone.. {%endcomment%} .. right?),
+    )
 
     assert_template_result('', '{%comment%}{%endcomment%}')
     assert_template_result('', '{%comment%}{% endcomment %}')
@@ -64,61 +68,81 @@ class StandardTagTest < Minitest::Test
 
   def test_capture
     assigns = { 'var' => 'content' }
-    assert_template_result('content foo content foo ',
+    assert_template_result(
+      'content foo content foo ',
       '{{ var2 }}{% capture var2 %}{{ var }} foo {% endcapture %}{{ var2 }}{{ var2 }}',
-      assigns)
+      assigns,
+    )
   end
 
   def test_capture_detects_bad_syntax
     assert_raises(SyntaxError) do
-      assert_template_result('content foo content foo ',
+      assert_template_result(
+        'content foo content foo ',
         '{{ var2 }}{% capture %}{{ var }} foo {% endcapture %}{{ var2 }}{{ var2 }}',
-        { 'var' => 'content' })
+        { 'var' => 'content' },
+      )
     end
   end
 
   def test_case
     assigns = { 'condition' => 2 }
-    assert_template_result(' its 2 ',
+    assert_template_result(
+      ' its 2 ',
       '{% case condition %}{% when 1 %} its 1 {% when 2 %} its 2 {% endcase %}',
-      assigns)
+      assigns,
+    )
 
     assigns = { 'condition' => 1 }
-    assert_template_result(' its 1 ',
+    assert_template_result(
+      ' its 1 ',
       '{% case condition %}{% when 1 %} its 1 {% when 2 %} its 2 {% endcase %}',
-      assigns)
+      assigns,
+    )
 
     assigns = { 'condition' => 3 }
-    assert_template_result('',
+    assert_template_result(
+      '',
       '{% case condition %}{% when 1 %} its 1 {% when 2 %} its 2 {% endcase %}',
-      assigns)
+      assigns,
+    )
 
     assigns = { 'condition' => "string here" }
-    assert_template_result(' hit ',
+    assert_template_result(
+      ' hit ',
       '{% case condition %}{% when "string here" %} hit {% endcase %}',
-      assigns)
+      assigns,
+    )
 
     assigns = { 'condition' => "bad string here" }
-    assert_template_result('',
+    assert_template_result(
+      '',
       '{% case condition %}{% when "string here" %} hit {% endcase %}',\
-      assigns)
+      assigns,
+    )
   end
 
   def test_case_with_else
     assigns = { 'condition' => 5 }
-    assert_template_result(' hit ',
+    assert_template_result(
+      ' hit ',
       '{% case condition %}{% when 5 %} hit {% else %} else {% endcase %}',
-      assigns)
+      assigns,
+    )
 
     assigns = { 'condition' => 6 }
-    assert_template_result(' else ',
+    assert_template_result(
+      ' else ',
       '{% case condition %}{% when 5 %} hit {% else %} else {% endcase %}',
-      assigns)
+      assigns,
+    )
 
     assigns = { 'condition' => 6 }
-    assert_template_result(' else ',
+    assert_template_result(
+      ' else ',
       '{% case condition %} {% when 5 %} hit {% else %} else {% endcase %}',
-      assigns)
+      assigns,
+    )
   end
 
   def test_case_on_size
@@ -131,47 +155,67 @@ class StandardTagTest < Minitest::Test
   end
 
   def test_case_on_size_with_else
-    assert_template_result('else',
+    assert_template_result(
+      'else',
       '{% case a.size %}{% when 1 %}1{% when 2 %}2{% else %}else{% endcase %}',
-      { 'a' => [] })
+      { 'a' => [] },
+    )
 
-    assert_template_result('1',
+    assert_template_result(
+      '1',
       '{% case a.size %}{% when 1 %}1{% when 2 %}2{% else %}else{% endcase %}',
-      { 'a' => [1] })
+      { 'a' => [1] },
+    )
 
-    assert_template_result('2',
+    assert_template_result(
+      '2',
       '{% case a.size %}{% when 1 %}1{% when 2 %}2{% else %}else{% endcase %}',
-      { 'a' => [1, 1] })
+      { 'a' => [1, 1] },
+    )
 
-    assert_template_result('else',
+    assert_template_result(
+      'else',
       '{% case a.size %}{% when 1 %}1{% when 2 %}2{% else %}else{% endcase %}',
-      { 'a' => [1, 1, 1] })
+      { 'a' => [1, 1, 1] },
+    )
 
-    assert_template_result('else',
+    assert_template_result(
+      'else',
       '{% case a.size %}{% when 1 %}1{% when 2 %}2{% else %}else{% endcase %}',
-      { 'a' => [1, 1, 1, 1] })
+      { 'a' => [1, 1, 1, 1] },
+    )
 
-    assert_template_result('else',
+    assert_template_result(
+      'else',
       '{% case a.size %}{% when 1 %}1{% when 2 %}2{% else %}else{% endcase %}',
-      { 'a' => [1, 1, 1, 1, 1] })
+      { 'a' => [1, 1, 1, 1, 1] },
+    )
   end
 
   def test_case_on_length_with_else
-    assert_template_result('else',
+    assert_template_result(
+      'else',
       '{% case a.empty? %}{% when true %}true{% when false %}false{% else %}else{% endcase %}',
-      {})
+      {},
+    )
 
-    assert_template_result('false',
+    assert_template_result(
+      'false',
       '{% case false %}{% when true %}true{% when false %}false{% else %}else{% endcase %}',
-      {})
+      {},
+    )
 
-    assert_template_result('true',
+    assert_template_result(
+      'true',
       '{% case true %}{% when true %}true{% when false %}false{% else %}else{% endcase %}',
-      {})
+      {},
+    )
 
-    assert_template_result('else',
+    assert_template_result(
+      'else',
       '{% case NULL %}{% when true %}true{% when false %}false{% else %}else{% endcase %}',
-      {})
+      {},
+    )
   end
 
   def test_assign_from_case
@@ -253,24 +297,33 @@ class StandardTagTest < Minitest::Test
 
     assert_template_result('one two one', '{%cycle "one", "two"%} {%cycle "one", "two"%} {%cycle "one", "two"%}')
 
-    assert_template_result('text-align: left text-align: right',
-      '{%cycle "text-align: left", "text-align: right" %} {%cycle "text-align: left", "text-align: right"%}')
+    assert_template_result(
+      'text-align: left text-align: right',
+      '{%cycle "text-align: left", "text-align: right" %} {%cycle "text-align: left", "text-align: right"%}',
+    )
   end
 
   def test_multiple_cycles
-    assert_template_result('1 2 1 1 2 3 1',
-      '{%cycle 1,2%} {%cycle 1,2%} {%cycle 1,2%} {%cycle 1,2,3%} {%cycle 1,2,3%} {%cycle 1,2,3%} {%cycle 1,2,3%}')
+    assert_template_result(
+      '1 2 1 1 2 3 1',
+      '{%cycle 1,2%} {%cycle 1,2%} {%cycle 1,2%} {%cycle 1,2,3%} {%cycle 1,2,3%} {%cycle 1,2,3%} {%cycle 1,2,3%}',
+    )
   end
 
   def test_multiple_named_cycles
-    assert_template_result('one one two two one one',
-      '{%cycle 1: "one", "two" %} {%cycle 2: "one", "two" %} {%cycle 1: "one", "two" %} {%cycle 2: "one", "two" %} {%cycle 1: "one", "two" %} {%cycle 2: "one", "two" %}')
+    assert_template_result(
+      'one one two two one one',
+      '{%cycle 1: "one", "two" %} {%cycle 2: "one", "two" %} {%cycle 1: "one", "two" %} {%cycle 2: "one", "two" %} {%cycle 1: "one", "two" %} {%cycle 2: "one", "two" %}',
+    )
   end
 
   def test_multiple_named_cycles_with_names_from_context
     assigns = { "var1" => 1, "var2" => 2 }
-    assert_template_result('one one two two one one',
-      '{%cycle var1: "one", "two" %} {%cycle var2: "one", "two" %} {%cycle var1: "one", "two" %} {%cycle var2: "one", "two" %} {%cycle var1: "one", "two" %} {%cycle var2: "one", "two" %}', assigns)
+    assert_template_result(
+      'one one two two one one',
+      '{%cycle var1: "one", "two" %} {%cycle var2: "one", "two" %} {%cycle var1: "one", "two" %} {%cycle var2: "one", "two" %} {%cycle var1: "one", "two" %} {%cycle var2: "one", "two" %}',
+      assigns,
+    )
   end
 
   def test_size_of_array

test/integration/tags/table_row_test.rb

@@ -18,52 +18,70 @@ class TableRowTest < Minitest::Test
   end
 
   def test_table_row
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
       '{% tablerow n in numbers cols:3%} {{n}} {% endtablerow %}',
-      { 'numbers' => [1, 2, 3, 4, 5, 6] })
+      { 'numbers' => [1, 2, 3, 4, 5, 6] },
+    )
 
-    assert_template_result("<tr class=\"row1\">\n</tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n</tr>\n",
       '{% tablerow n in numbers cols:3%} {{n}} {% endtablerow %}',
-      { 'numbers' => [] })
+      { 'numbers' => [] },
+    )
   end
 
   def test_table_row_with_different_cols
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td><td class=\"col4\"> 4 </td><td class=\"col5\"> 5 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 6 </td></tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td><td class=\"col4\"> 4 </td><td class=\"col5\"> 5 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 6 </td></tr>\n",
       '{% tablerow n in numbers cols:5%} {{n}} {% endtablerow %}',
-      { 'numbers' => [1, 2, 3, 4, 5, 6] })
+      { 'numbers' => [1, 2, 3, 4, 5, 6] },
+    )
   end
 
   def test_table_col_counter
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\">1</td><td class=\"col2\">2</td></tr>\n<tr class=\"row2\"><td class=\"col1\">1</td><td class=\"col2\">2</td></tr>\n<tr class=\"row3\"><td class=\"col1\">1</td><td class=\"col2\">2</td></tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\">1</td><td class=\"col2\">2</td></tr>\n<tr class=\"row2\"><td class=\"col1\">1</td><td class=\"col2\">2</td></tr>\n<tr class=\"row3\"><td class=\"col1\">1</td><td class=\"col2\">2</td></tr>\n",
       '{% tablerow n in numbers cols:2%}{{tablerowloop.col}}{% endtablerow %}',
-      { 'numbers' => [1, 2, 3, 4, 5, 6] })
+      { 'numbers' => [1, 2, 3, 4, 5, 6] },
+    )
   end
 
   def test_quoted_fragment
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
       "{% tablerow n in collections.frontpage cols:3%} {{n}} {% endtablerow %}",
-      { 'collections' => { 'frontpage' => [1, 2, 3, 4, 5, 6] } })
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
+      { 'collections' => { 'frontpage' => [1, 2, 3, 4, 5, 6] } },
+    )
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
       "{% tablerow n in collections['frontpage'] cols:3%} {{n}} {% endtablerow %}",
-      { 'collections' => { 'frontpage' => [1, 2, 3, 4, 5, 6] } })
+      { 'collections' => { 'frontpage' => [1, 2, 3, 4, 5, 6] } },
+    )
   end
 
   def test_enumerable_drop
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
       '{% tablerow n in numbers cols:3%} {{n}} {% endtablerow %}',
-      { 'numbers' => ArrayDrop.new([1, 2, 3, 4, 5, 6]) })
+      { 'numbers' => ArrayDrop.new([1, 2, 3, 4, 5, 6]) },
+    )
   end
 
   def test_offset_and_limit
-    assert_template_result("<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td><td class=\"col3\"> 3 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 4 </td><td class=\"col2\"> 5 </td><td class=\"col3\"> 6 </td></tr>\n",
       '{% tablerow n in numbers cols:3 offset:1 limit:6%} {{n}} {% endtablerow %}',
-      { 'numbers' => [0, 1, 2, 3, 4, 5, 6, 7] })
+      { 'numbers' => [0, 1, 2, 3, 4, 5, 6, 7] },
+    )
   end
 
   def test_blank_string_not_iterable
-    assert_template_result("<tr class=\"row1\">\n</tr>\n",
+    assert_template_result(
+      "<tr class=\"row1\">\n</tr>\n",
       "{% tablerow char in characters cols:3 %}I WILL NOT BE OUTPUT{% endtablerow %}",
-      { 'characters' => '' })
+      { 'characters' => '' },
+    )
   end
 
   def test_cols_nil_constant_same_as_evaluated_nil_expression
@@ -72,12 +90,50 @@ class TableRowTest < Minitest::Test
       "<td class=\"col2\">false</td>" \
       "</tr>\n"
 
-    assert_template_result(expect,
-      "{% tablerow i in (1..2) cols:nil %}{{ tablerowloop.col_last }}{% endtablerow %}")
+    assert_template_result(
+      expect,
+      "{% tablerow i in (1..2) cols:nil %}{{ tablerowloop.col_last }}{% endtablerow %}",
+    )
 
-    assert_template_result(expect,
+    assert_template_result(
+      expect,
       "{% tablerow i in (1..2) cols:var %}{{ tablerowloop.col_last }}{% endtablerow %}",
-      { "var" => nil })
+      { "var" => nil },
+    )
+  end
+
+  def test_nil_limit_is_treated_as_zero
+    expect = "<tr class=\"row1\">\n" \
+      "</tr>\n"
+
+    assert_template_result(
+      expect,
+      "{% tablerow i in (1..2) limit:nil %}{{ i }}{% endtablerow %}",
+    )
+
+    assert_template_result(
+      expect,
+      "{% tablerow i in (1..2) limit:var %}{{ i }}{% endtablerow %}",
+      { "var" => nil },
+    )
+  end
+
+  def test_nil_offset_is_treated_as_zero
+    expect = "<tr class=\"row1\">\n" \
+      "<td class=\"col1\">1:false</td>" \
+      "<td class=\"col2\">2:true</td>" \
+      "</tr>\n"
+
+    assert_template_result(
+      expect,
+      "{% tablerow i in (1..2) offset:nil %}{{ i }}:{{ tablerowloop.col_last }}{% endtablerow %}",
+    )
+
+    assert_template_result(
+      expect,
+      "{% tablerow i in (1..2) offset:var %}{{ i }}:{{ tablerowloop.col_last }}{% endtablerow %}",
+      { "var" => nil },
+    )
   end
 
   def test_tablerow_loop_drop_attributes
@@ -131,4 +187,72 @@ class TableRowTest < Minitest::Test
 
     assert_template_result(expected_output, template)
   end
+
+  def test_table_row_renders_correct_error_message_for_invalid_parameters
+    assert_template_result(
+      "Liquid error (line 1): invalid integer",
+      '{% tablerow n in (1...10) limit:true %} {{n}} {% endtablerow %}',
+      render_errors: true,
+    )
+
+    assert_template_result(
+      "Liquid error (line 1): invalid integer",
+      '{% tablerow n in (1...10) offset:true %} {{n}} {% endtablerow %}',
+      render_errors: true,
+    )
+
+    assert_template_result(
+      "Liquid error (line 1): invalid integer",
+      '{% tablerow n in (1...10) cols:true %} {{n}} {% endtablerow %}',
+      render_errors: true,
+    )
+  end
+
+  def test_table_row_handles_interrupts
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td></tr>\n",
+      '{% tablerow n in (1...3) cols:2 %} {{n}} {% break %} {{n}} {% endtablerow %}',
+    )
+
+    assert_template_result(
+      "<tr class=\"row1\">\n<td class=\"col1\"> 1 </td><td class=\"col2\"> 2 </td></tr>\n<tr class=\"row2\"><td class=\"col1\"> 3 </td></tr>\n",
+      '{% tablerow n in (1...3) cols:2 %} {{n}} {% continue %} {{n}} {% endtablerow %}',
+    )
+  end
+
+  def test_table_row_does_not_leak_interrupts
+    template = <<~LIQUID
+      {% for i in (1..2) -%}
+      {% for j in (1..2) -%}
+      {% tablerow k in (1..3) %}{% break %}{% endtablerow -%}
+      loop j={{ j }}
+      {% endfor -%}
+      loop i={{ i }}
+      {% endfor -%}
+      after loop
+    LIQUID
+
+    expected = <<~STR
+      <tr class="row1">
+      <td class="col1"></td></tr>
+      loop j=1
+      <tr class="row1">
+      <td class="col1"></td></tr>
+      loop j=2
+      loop i=1
+      <tr class="row1">
+      <td class="col1"></td></tr>
+      loop j=1
+      <tr class="row1">
+      <td class="col1"></td></tr>
+      loop j=2
+      loop i=2
+      after loop
+    STR
+
+    assert_template_result(
+      expected,
+      template,
+    )
+  end
 end

test/integration/tags/unless_else_tag_test.rb

@@ -7,8 +7,10 @@ class UnlessElseTagTest < Minitest::Test
 
   def test_unless
     assert_template_result('  ', ' {% unless true %} this text should not go into the output {% endunless %} ')
-    assert_template_result('  this text should go into the output  ',
-      ' {% unless false %} this text should go into the output {% endunless %} ')
+    assert_template_result(
+      '  this text should go into the output  ',
+      ' {% unless false %} this text should go into the output {% endunless %} ',
+    )
     assert_template_result('  you rock ?', '{% unless true %} you suck {% endunless %} {% unless false %} you rock {% endunless %}?')
   end
 

test/integration/template_test.rb

@@ -93,10 +93,12 @@ class TemplateTest < Minitest::Test
 
   def test_lambda_is_called_once_from_custom_assigns_over_multiple_parses_and_renders
     t = Template.new
-    assigns = { 'number' => -> {
-                              @global ||= 0
-                              @global  += 1
-                            } }
+    assigns = {
+      'number' => -> {
+        @global ||= 0
+        @global += 1
+      },
+    }
     assert_equal('1', t.parse("{{number}}").render!(assigns))
     assert_equal('1', t.parse("{{number}}").render!(assigns))
     assert_equal('1', t.render!(assigns))
@@ -335,4 +337,22 @@ class TemplateTest < Minitest::Test
     assert_equal("x=2", output)
     assert_instance_of(String, output)
   end
+
+  def test_raises_error_with_invalid_utf8
+    e = assert_raises(TemplateEncodingError) do
+      Template.parse(<<~LIQUID)
+        {% comment %}
+          \xC0
+        {% endcomment %}
+      LIQUID
+    end
+
+    assert_equal('Liquid error: Invalid template encoding', e.message)
+  end
+
+  def test_allows_non_string_values_as_source
+    assert_equal('', Template.parse(nil).render)
+    assert_equal('1', Template.parse(1).render)
+    assert_equal('true', Template.parse(true).render)
+  end
 end

test/integration/variable_test.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'test_helper'
+require 'timeout'
 
 class VariableTest < Minitest::Test
   include Liquid
@@ -24,17 +25,23 @@ class VariableTest < Minitest::Test
 
   def test_if_tag_calls_to_liquid_value
     assert_template_result('one', '{% if foo == 1 %}one{% endif %}', { 'foo' => IntegerDrop.new('1') })
+    assert_template_result('one', '{% if foo == eqv %}one{% endif %}', { 'foo' => IntegerDrop.new(1), 'eqv' => IntegerDrop.new(1) })
     assert_template_result('one', '{% if 0 < foo %}one{% endif %}', { 'foo' => IntegerDrop.new('1') })
     assert_template_result('one', '{% if foo > 0 %}one{% endif %}', { 'foo' => IntegerDrop.new('1') })
+    assert_template_result('one', '{% if b > a %}one{% endif %}', { 'b' => IntegerDrop.new(1), 'a' => IntegerDrop.new(0) })
     assert_template_result('true', '{% if foo == true %}true{% endif %}', { 'foo' => BooleanDrop.new(true) })
     assert_template_result('true', '{% if foo %}true{% endif %}', { 'foo' => BooleanDrop.new(true) })
 
     assert_template_result('', '{% if foo %}true{% endif %}', { 'foo' => BooleanDrop.new(false) })
     assert_template_result('', '{% if foo == true %}True{% endif %}', { 'foo' => BooleanDrop.new(false) })
+    assert_template_result('', '{% if foo and true %}SHOULD NOT HAPPEN{% endif %}', { 'foo' => BooleanDrop.new(false) })
+
+    assert_template_result('one', '{% if a contains x %}one{% endif %}', { 'a' => [1], 'x' => IntegerDrop.new(1) })
   end
 
   def test_unless_tag_calls_to_liquid_value
     assert_template_result('', '{% unless foo %}true{% endunless %}', { 'foo' => BooleanDrop.new(true) })
+    assert_template_result('true', '{% unless foo %}true{% endunless %}', { 'foo' => BooleanDrop.new(false) })
   end
 
   def test_case_tag_calls_to_liquid_value
@@ -130,4 +137,72 @@ class VariableTest < Minitest::Test
   def test_raw_value_variable
     assert_template_result('bar', '{{ [key] }}', { 'key' => 'foo', 'foo' => 'bar' })
   end
+
+  def test_dynamic_find_var_with_drop
+    assert_template_result(
+      'bar',
+      '{{ [list[settings.zero]] }}',
+      {
+        'list' => ['foo'],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'foo' => 'bar',
+      },
+    )
+
+    assert_template_result(
+      'foo',
+      '{{ [list[settings.zero]["foo"]] }}',
+      {
+        'list' => [{ 'foo' => 'bar' }],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'bar' => 'foo',
+      },
+    )
+  end
+
+  def test_double_nested_variable_lookup
+    assert_template_result(
+      'bar',
+      '{{ list[list[settings.zero]]["foo"] }}',
+      {
+        'list' => [1, { 'foo' => 'bar' }],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'bar' => 'foo',
+      },
+    )
+  end
+
+  def test_variable_lookup_should_not_hang_with_invalid_syntax
+    Timeout.timeout(1) do
+      assert_template_result(
+        'bar',
+        "{{['foo'}}",
+        {
+          'foo' => 'bar',
+        },
+        error_mode: :lax,
+      )
+    end
+
+    very_long_key = "1234567890" * 100
+
+    template_list = [
+      "{{['#{very_long_key}']}}", # valid
+      "{{['#{very_long_key}'}}", # missing closing bracket
+      "{{[['#{very_long_key}']}}", # extra open bracket
+    ]
+
+    template_list.each do |template|
+      Timeout.timeout(1) do
+        assert_template_result(
+          'bar',
+          template,
+          {
+            very_long_key => 'bar',
+          },
+          error_mode: :lax,
+        )
+      end
+    end
+  end
 end

test/test_helper.rb

@@ -13,7 +13,7 @@ if (env_mode = ENV['LIQUID_PARSER_MODE'])
   puts "-- #{env_mode.upcase} ERROR MODE"
   mode = env_mode.to_sym
 end
-Liquid::Template.error_mode = mode
+Liquid::Environment.default.error_mode = mode
 
 if ENV['LIQUID_C'] == '1'
   puts "-- LIQUID C"
@@ -39,37 +39,18 @@ module Minitest
 
     def assert_template_result(
       expected, template, assigns = {},
-      message: nil, partials: nil, error_mode: nil, render_errors: false
+      message: nil, partials: nil, error_mode: nil, render_errors: false,
+      template_factory: nil
     )
-      template = Liquid::Template.parse(template, line_numbers: true, error_mode: error_mode&.to_sym)
       file_system = StubFileSystem.new(partials || {})
-      registers = Liquid::Registers.new(file_system: file_system)
-      context = Liquid::Context.build(static_environments: assigns, rethrow_errors: !render_errors, registers: registers)
+      environment = Liquid::Environment.build(file_system: file_system)
+      template = Liquid::Template.parse(template, line_numbers: true, error_mode: error_mode&.to_sym, environment: environment)
+      registers = Liquid::Registers.new(file_system: file_system, template_factory: template_factory)
+      context = Liquid::Context.build(static_environments: assigns, rethrow_errors: !render_errors, registers: registers, environment: environment)
       output = template.render(context)
       assert_equal(expected, output, message)
     end
 
-    if ENV['LIQUID_MIGRATOR']
-      puts "-- Liquid Migrator Enabled"
-
-      alias_method(:assert_template_result_without_migrator, :assert_template_result)
-
-      def assert_template_result(expected, source, assigns = {}, error_mode: nil, partials: nil, **kwargs)
-        migrated_source = Liquid::Template.migrate(source, line_numbers: true, error_mode: error_mode&.to_sym)
-        assert_no_migration(migrated_source)
-        if partials
-          migrated_partials = {}
-          partials.each do |name, partial|
-            new_partial = Liquid::Template.migrate(partial, line_numbers: true, error_mode: error_mode&.to_sym)
-            assert_no_migration(new_partial)
-            migrated_partials[name] = new_partial
-          end
-        end
-        assert_template_result_without_migrator(expected, migrated_source, assigns,
-          error_mode: 'strict', partials: migrated_partials, **kwargs)
-      end
-    end
-
     def assert_match_syntax_error(match, template, error_mode: nil)
       exception = assert_raises(Liquid::SyntaxError) do
         Template.parse(template, line_numbers: true, error_mode: error_mode&.to_sym).render
@@ -81,10 +62,6 @@ module Minitest
       assert_match_syntax_error("", template, error_mode: error_mode)
     end
 
-    def assert_no_migration(source)
-      assert_equal(source, Liquid::Template.migrate(source))
-    end
-
     def assert_usage_increment(name, times: 1)
       old_method = Liquid::Usage.method(:increment)
       calls = 0
@@ -102,44 +79,27 @@ module Minitest
       assert_equal(times, calls, "Number of calls to Usage.increment with #{name.inspect}")
     end
 
-    def with_global_filter(*globals)
-      original_global_cache = Liquid::StrainerFactory::GlobalCache
-      Liquid::StrainerFactory.send(:remove_const, :GlobalCache)
-      Liquid::StrainerFactory.const_set(:GlobalCache, Class.new(Liquid::StrainerTemplate))
+    def with_global_filter(*globals, &blk)
+      environment = Liquid::Environment.build do |w|
+        w.register_filters(globals)
+      end
 
-      globals.each do |global|
-        Liquid::Template.register_filter(global)
-      end
-      Liquid::StrainerFactory.send(:strainer_class_cache).clear
-      begin
-        yield
-      ensure
-        Liquid::StrainerFactory.send(:remove_const, :GlobalCache)
-        Liquid::StrainerFactory.const_set(:GlobalCache, original_global_cache)
-        Liquid::StrainerFactory.send(:strainer_class_cache).clear
-      end
+      Environment.dangerously_override(environment, &blk)
     end
 
     def with_error_mode(mode)
-      old_mode = Liquid::Template.error_mode
-      Liquid::Template.error_mode = mode
+      old_mode = Liquid::Environment.default.error_mode
+      Liquid::Environment.default.error_mode = mode
       yield
     ensure
-      Liquid::Template.error_mode = old_mode
+      Liquid::Environment.default.error_mode = old_mode
     end
 
-    def with_custom_tag(tag_name, tag_class)
-      old_tag = Liquid::Template.tags[tag_name]
-      begin
-        Liquid::Template.register_tag(tag_name, tag_class)
-        yield
-      ensure
-        if old_tag
-          Liquid::Template.tags[tag_name] = old_tag
-        else
-          Liquid::Template.tags.delete(tag_name)
-        end
-      end
+    def with_custom_tag(tag_name, tag_class, &block)
+      environment = Liquid::Environment.default.dup
+      environment.register_tag(tag_name, tag_class)
+
+      Environment.dangerously_override(environment, &block)
     end
   end
 end
@@ -150,16 +110,23 @@ class ThingWithToLiquid
   end
 end
 
+class SettingsDrop < Liquid::Drop
+  def initialize(settings)
+    super()
+    @settings = settings
+  end
+
+  def liquid_method_missing(key)
+    @settings[key]
+  end
+end
+
 class IntegerDrop < Liquid::Drop
   def initialize(value)
     super()
     @value = value.to_i
   end
 
-  def ==(other)
-    @value == other
-  end
-
   def to_s
     @value.to_s
   end
@@ -175,10 +142,6 @@ class BooleanDrop < Liquid::Drop
     @value = value
   end
 
-  def ==(other)
-    @value == other
-  end
-
   def to_liquid_value
     @value
   end
@@ -231,8 +194,10 @@ class StubTemplateFactory
     @count = 0
   end
 
-  def for(_template_name)
+  def for(template_name)
     @count += 1
-    Liquid::Template.new
+    template = Liquid::Template.new
+    template.name = "some/path/" + template_name
+    template
   end
 end

test/unit/block_unit_test.rb

@@ -32,11 +32,19 @@ class BlockUnitTest < Minitest::Test
     assert_equal(String, template.root.nodelist[2].class)
   end
 
+  def test_variable_with_multibyte_character
+    template = Liquid::Template.parse("{{ '❤️' }}")
+    assert_equal(1, template.root.nodelist.size)
+    assert_equal(Variable, template.root.nodelist[0].class)
+  end
+
   def test_variable_many_embedded_fragments
     template = Liquid::Template.parse("  {{funk}} {{so}} {{brother}} ")
     assert_equal(7, template.root.nodelist.size)
-    assert_equal([String, Variable, String, Variable, String, Variable, String],
-      block_types(template.root.nodelist))
+    assert_equal(
+      [String, Variable, String, Variable, String, Variable, String],
+      block_types(template.root.nodelist),
+    )
   end
 
   def test_with_block

test/unit/condition_unit_test.rb

@@ -55,6 +55,11 @@ class ConditionUnitTest < Minitest::Test
     assert_evaluates_false('bob', 'contains', '---')
   end
 
+  def test_contains_binary_encoding_compatibility_with_utf8
+    assert_evaluates_true('🙈'.b, 'contains', '🙈')
+    assert_evaluates_true('🙈', 'contains', '🙈'.b)
+  end
+
   def test_invalid_comparation_operator
     assert_evaluates_argument_error(1, '~~', 0)
   end
@@ -164,13 +169,17 @@ class ConditionUnitTest < Minitest::Test
   private
 
   def assert_evaluates_true(left, op, right)
-    assert(Condition.new(left, op, right).evaluate(@context),
-      "Evaluated false: #{left} #{op} #{right}")
+    assert(
+      Condition.new(left, op, right).evaluate(@context),
+      "Evaluated false: #{left.inspect} #{op} #{right.inspect}",
+    )
   end
 
   def assert_evaluates_false(left, op, right)
-    assert(!Condition.new(left, op, right).evaluate(@context),
-      "Evaluated true: #{left} #{op} #{right}")
+    assert(
+      !Condition.new(left, op, right).evaluate(@context),
+      "Evaluated true: #{left.inspect} #{op} #{right.inspect}",
+    )
   end
 
   def assert_evaluates_argument_error(left, op, right)

test/unit/environment_filter_test.rb

@@ -2,7 +2,7 @@
 
 require 'test_helper'
 
-class StrainerFactoryUnitTest < Minitest::Test
+class EnvironmentFilterTest < Minitest::Test
   include Liquid
 
   module AccessScopeFilters
@@ -16,8 +16,6 @@ class StrainerFactoryUnitTest < Minitest::Test
     private :private_filter
   end
 
-  StrainerFactory.add_global_filter(AccessScopeFilters)
-
   module LateAddedFilter
     def late_added_filter(_input)
       "filtered"
@@ -25,24 +23,28 @@ class StrainerFactoryUnitTest < Minitest::Test
   end
 
   def setup
-    @context = Context.build
+    @environment = Liquid::Environment.build do |env|
+      env.register_filter(AccessScopeFilters)
+    end
+
+    @context = Context.build(environment: @environment)
   end
 
   def test_strainer
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
     assert_equal(5, strainer.invoke('size', 'input'))
     assert_equal("public", strainer.invoke("public_filter"))
   end
 
   def test_stainer_raises_argument_error
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
     assert_raises(Liquid::ArgumentError) do
       strainer.invoke("public_filter", 1)
     end
   end
 
   def test_stainer_argument_error_contains_backtrace
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
 
     exception = assert_raises(Liquid::ArgumentError) do
       strainer.invoke("public_filter", 1)
@@ -50,14 +52,14 @@ class StrainerFactoryUnitTest < Minitest::Test
 
     assert_match(
       /\ALiquid error: wrong number of arguments \((1 for 0|given 1, expected 0)\)\z/,
-      exception.message
+      exception.message,
     )
     source = AccessScopeFilters.instance_method(:public_filter).source_location
     assert_equal(source.map(&:to_s), exception.backtrace[0].split(':')[0..1])
   end
 
   def test_strainer_only_invokes_public_filter_methods
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
     assert_equal(false, strainer.class.invokable?('__test__'))
     assert_equal(false, strainer.class.invokable?('test'))
     assert_equal(false, strainer.class.invokable?('instance_eval'))
@@ -66,18 +68,18 @@ class StrainerFactoryUnitTest < Minitest::Test
   end
 
   def test_strainer_returns_nil_if_no_filter_method_found
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
     assert_nil(strainer.invoke("private_filter"))
     assert_nil(strainer.invoke("undef_the_filter"))
   end
 
   def test_strainer_returns_first_argument_if_no_method_and_arguments_given
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
     assert_equal("password", strainer.invoke("undef_the_method", "password"))
   end
 
   def test_strainer_only_allows_methods_defined_in_filters
-    strainer = StrainerFactory.create(@context)
+    strainer = @environment.create_strainer(@context)
     assert_equal("1 + 1", strainer.invoke("instance_eval", "1 + 1"))
     assert_equal("puts",  strainer.invoke("__send__", "puts", "Hi Mom"))
     assert_equal("has_method?", strainer.invoke("invoke", "has_method?", "invoke"))
@@ -86,7 +88,9 @@ class StrainerFactoryUnitTest < Minitest::Test
   def test_strainer_uses_a_class_cache_to_avoid_method_cache_invalidation
     a = Module.new
     b = Module.new
-    strainer = StrainerFactory.create(@context, [a, b])
+
+    strainer = @environment.create_strainer(@context, [a, b])
+
     assert_kind_of(StrainerTemplate, strainer)
     assert_kind_of(a, strainer)
     assert_kind_of(b, strainer)
@@ -94,8 +98,10 @@ class StrainerFactoryUnitTest < Minitest::Test
   end
 
   def test_add_global_filter_clears_cache
-    assert_equal('input', StrainerFactory.create(@context).invoke('late_added_filter', 'input'))
-    StrainerFactory.add_global_filter(LateAddedFilter)
-    assert_equal('filtered', StrainerFactory.create(nil).invoke('late_added_filter', 'input'))
+    assert_equal('input', @environment.create_strainer(@context).invoke('late_added_filter', 'input'))
+
+    @environment.register_filter(LateAddedFilter)
+
+    assert_equal('filtered', @environment.create_strainer(nil).invoke('late_added_filter', 'input'))
   end
 end

test/unit/lexer_unit_test.rb

@@ -6,48 +6,134 @@ class LexerUnitTest < Minitest::Test
   include Liquid
 
   def test_strings
-    tokens = Lexer.new(%( 'this is a test""' "wat 'lol'")).tokenize
-    assert_equal([[:string, %('this is a test""')], [:string, %("wat 'lol'")], [:end_of_string]], tokens)
+    assert_equal(
+      [[:string, %('this is a test""')], [:string, %("wat 'lol'")], [:end_of_string]],
+      tokenize(%( 'this is a test""' "wat 'lol'")),
+    )
   end
 
   def test_integer
-    tokens = Lexer.new('hi 50').tokenize
-    assert_equal([[:id, 'hi'], [:number, '50'], [:end_of_string]], tokens)
+    assert_equal(
+      [[:id, 'hi'], [:number, '50'], [:end_of_string]],
+      tokenize('hi 50'),
+    )
   end
 
   def test_float
-    tokens = Lexer.new('hi 5.0').tokenize
-    assert_equal([[:id, 'hi'], [:number, '5.0'], [:end_of_string]], tokens)
+    assert_equal(
+      [[:id, 'hi'], [:number, '5.0'], [:end_of_string]],
+      tokenize('hi 5.0'),
+    )
   end
 
   def test_comparison
-    tokens = Lexer.new('== <> contains ').tokenize
-    assert_equal([[:comparison, '=='], [:comparison, '<>'], [:comparison, 'contains'], [:end_of_string]], tokens)
+    assert_equal(
+      [[:comparison, '=='], [:comparison, '<>'], [:comparison, 'contains'], [:end_of_string]],
+      tokenize('== <> contains '),
+    )
+  end
+
+  def test_comparison_without_whitespace
+    assert_equal(
+      [[:number, '1'], [:comparison, '>'], [:number, '0'], [:end_of_string]],
+      tokenize('1>0'),
+    )
+  end
+
+  def test_comparison_with_negative_number
+    assert_equal(
+      [[:number, '1'], [:comparison, '>'], [:number, '-1'], [:end_of_string]],
+      tokenize('1>-1'),
+    )
+  end
+
+  def test_raise_for_invalid_comparison
+    assert_raises(SyntaxError) do
+      tokenize('1>!1')
+    end
+
+    assert_raises(SyntaxError) do
+      tokenize('1=<1')
+    end
+
+    assert_raises(SyntaxError) do
+      tokenize('1!!1')
+    end
   end
 
   def test_specials
-    tokens = Lexer.new('| .:').tokenize
-    assert_equal([[:pipe, '|'], [:dot, '.'], [:colon, ':'], [:end_of_string]], tokens)
-    tokens = Lexer.new('[,]').tokenize
-    assert_equal([[:open_square, '['], [:comma, ','], [:close_square, ']'], [:end_of_string]], tokens)
+    assert_equal(
+      [[:pipe, '|'], [:dot, '.'], [:colon, ':'], [:end_of_string]],
+      tokenize('| .:'),
+    )
+
+    assert_equal(
+      [[:open_square, '['], [:comma, ','], [:close_square, ']'], [:end_of_string]],
+      tokenize('[,]'),
+    )
   end
 
   def test_fancy_identifiers
-    tokens = Lexer.new('hi five?').tokenize
-    assert_equal([[:id, 'hi'], [:id, 'five?'], [:end_of_string]], tokens)
+    assert_equal([[:id, 'hi'], [:id, 'five?'], [:end_of_string]], tokenize('hi five?'))
 
-    tokens = Lexer.new('2foo').tokenize
-    assert_equal([[:number, '2'], [:id, 'foo'], [:end_of_string]], tokens)
+    assert_equal([[:number, '2'], [:id, 'foo'], [:end_of_string]], tokenize('2foo'))
   end
 
   def test_whitespace
-    tokens = Lexer.new("five|\n\t ==").tokenize
-    assert_equal([[:id, 'five'], [:pipe, '|'], [:comparison, '=='], [:end_of_string]], tokens)
+    assert_equal(
+      [[:id, 'five'], [:pipe, '|'], [:comparison, '=='], [:end_of_string]],
+      tokenize("five|\n\t =="),
+    )
   end
 
   def test_unexpected_character
     assert_raises(SyntaxError) do
-      Lexer.new("%").tokenize
+      tokenize("%")
     end
   end
+
+  def test_negative_numbers
+    assert_equal(
+      [[:id, 'foo'], [:pipe, '|'], [:id, 'default'], [:colon, ":"], [:number, '-1'], [:end_of_string]],
+      tokenize("foo | default: -1"),
+    )
+  end
+
+  def test_greater_than_two_digits
+    assert_equal(
+      [[:id, 'foo'], [:comparison, '>'], [:number, '12'], [:end_of_string]],
+      tokenize("foo > 12"),
+    )
+  end
+
+  def test_error_with_utf8_character
+    error = assert_raises(SyntaxError) do
+      tokenize("1 < 1Ø")
+    end
+
+    assert_equal(
+      'Liquid syntax error: Unexpected character Ø',
+      error.message,
+    )
+  end
+
+  def test_contains_as_attribute_name
+    assert_equal(
+      [[:id, "a"], [:dot, "."], [:id, "contains"], [:dot, "."], [:id, "b"], [:end_of_string]],
+      tokenize("a.contains.b"),
+    )
+  end
+
+  def test_tokenize_incomplete_expression
+    assert_equal([[:id, "false"], [:dash, "-"], [:end_of_string]], tokenize("false -"))
+    assert_equal([[:id, "false"], [:comparison, "<"], [:end_of_string]], tokenize("false <"))
+    assert_equal([[:id, "false"], [:comparison, ">"], [:end_of_string]], tokenize("false >"))
+    assert_equal([[:id, "false"], [:number, "1"], [:end_of_string]], tokenize("false 1"))
+  end
+
+  private
+
+  def tokenize(input)
+    Lexer.new(input).tokenize
+  end
 end

test/unit/migrate_unit_test.rb

@@ -1,133 +0,0 @@
-# frozen_string_literal: true
-
-require 'test_helper'
-
-class MigrateUnitTest < Minitest::Test
-  def test_migrate_preserves_valid_markup
-    [
-      "{{a}}",
-      " {{- \ta\n -}} ",
-      "{{a.b['c'].d[5]|default:6,allow_false:true|truncate:7,'..'}}",
-      "{{ a . b [ 'c' ] . d [ 5 ] | default : 6 , allow_false : true | truncate :  4 , '..'  }}",
-      "{%assign x=a.b['c'].d[5]|default:6,allow_false:true|truncate:7,'..'%}",
-      "{% assign x =\na . b [ 'c' ] . d [ 5 ] | default : 6 , allow_false : true | truncate :  4 , '..'  %}",
-      "{% if a and b > c %}A{% elsif d or f contains g %}B{% else %}C{% endif %}",
-      <<~LIQUID,
-        {% liquid
-          if x > 0
-            assign x = x | plus: 1
-
-          endif
-        %}
-      LIQUID
-    ].each do |source|
-      assert_no_migration(source)
-    end
-  end
-
-  def test_migrate_variable
-    with_error_mode(:lax) do
-      assert_migration({
-        %({{ ,|"' }}) => "{{  }}", # no MarkupWithQuotedFragment match, skipping characters
-        %({{ ,|"' 123 }}) => "{{  123 }}", # MarkupWithQuotedFragment skipped characters
-        "{{,-2}}" => "{{ -2}}", # preserve separators when removing ignored characters
-        "{{  12 34  }}" => "{{  12  }}", # no FilterMarkupRegex match, skipping characters
-        "{{ -12 34 | abs }}" => "{{ -12 | abs }}", # FilterMarkupRegex skipped characters
-        %({{ -12 | '" abs }}) => "{{ -12 |  abs }}", # FilterParser skipped characters
-        "{{ -1 | abs ' plus: 1 }}" => "{{ -1 | abs | plus: 1 }}", # FilterParser unexpected separator
-        "{{ -1 | ! abs }}" => "{{ -1 | abs }}", # ignored non-word characters preceding filter name
-        "{{ 'a' | append WAT: 'b' }}" => "{{ 'a' | append : 'b' }}", # FilterArgsRegex skipped characters
-        "{{ '!' | replace, '!': '?' }}" => "{{ '!' | replace: '!', '?' }}", # FilterArgsRegex unexpected separators
-        "{{ -a.1b }}" => "{{ ['-a']['1b'] }}", # quote separators when removing ignored characters
-      })
-    end
-  end
-
-  def test_migrate_expression
-    with_error_mode(:lax) do
-      assert_migration({
-        "{{ (1.9...2.8) }}" => "{{ (1..2) }}", # apply constant range coercion
-        "{{ 1.2.3.4 }}" => "{{ 1.2 }}", # multiple periods allowed by FLOATS_REGEX, truncated by to_f
-        "{{ 1. }}" => "{{ 1.0 }}", # FLOATS_REGEX didn't require digits after the period
-        "{{ .empty }}" => "{{ ['empty'] }}", # skipped character prevents exact literal lookup
-      })
-    end
-  end
-
-  def test_migrate_variable_lookup
-    with_error_mode(:lax) do
-      assert_migration({
-        "{{@a[b].c@}}" => "{{ a[b].c }}", # VariableParser skipped characters
-        "{{ a!b$c }}" => "{{ a.b.c }}", # VariableParser unexpected separators
-      })
-    end
-  end
-
-  def test_migrate_assign
-    with_error_mode(:lax) do
-      assert_migration({
-        "{% assign!a = b!%}" => "{% assign a = b %}", # Syntax skipped characters
-        "{% assign a = @b ! %}" => "{% assign a =  b %}", # Variable skipped characters
-        "{% assign|x=1 %}" => "{% assign x=1 %}", # ensure tag name separated from markup
-      })
-    end
-  end
-
-  def test_lax_migrate_if
-    with_error_mode(:lax) do
-      assert_migration({
-        "{% if@a@%}Y{% endif %}" => "{% if a %}Y{% endif %}", # Syntax skipped character
-        "{% if &a contains^b and *c %}A{% elsif %d or$e %}B{% endif %}" =>
-          "{% if  a contains b and  c %}A{% elsif  d or e %}B{% endif %}", # test more expressions
-        "{% if b 1 %}Y{% endif %}" => "{% if b  %}Y{% endif %}", # missing operator with right operand
-        "{% if c == %}Y{% endif %}" => "{% if c == nil %}Y{% endif %}", # operator with missing right operand
-        "{% if!a!%}T{% endif %}" => "{% if a %}T{% endif %}", # VariableParser skipped characters
-        "{% if!%}T{% endif %}" => "{% if nil %}T{% endif %}", # VariableParser skipping all characters
-      })
-    end
-  end
-
-  def test_migrate_liquid_tag
-    with_error_mode(:lax) do
-      source = <<~LIQUID
-        {% liquid
-          assign ! a = 1
-          assign a = @b !
-        %}
-      LIQUID
-      expect = <<~LIQUID
-        {% liquid
-          assign  a = 1
-          assign a =  b
-        %}
-      LIQUID
-      assert_migration({ source => expect })
-    end
-  end
-
-  def test_migrate_for
-    with_error_mode(:lax) do
-      assert_migration({
-        # VariableLookup ignored character
-        "{% for i in !array %}x{% endfor %}" => "{% for i in  array %}x{% endfor %}",
-
-        # TagAttributes scanned over separators
-        "{% for i in array|offset: 1|limit: 5 %}x{% endfor %}" => "{% for i in array, offset: 1, limit: 5 %}x{% endfor %}",
-
-        # TagAttributes scans all the markup, which can overlap with what Syntax already matched
-        "{% for i in foo.offset: wat %}x{% endfor %}" => "{% for i in foo.offset , offset: wat %}x{% endfor %}",
-      })
-    end
-  end
-
-  private
-
-  def assert_migration(source_to_expected_output_hash)
-    source_to_expected_output_hash.each do |source, expect|
-      message = "source: #{source.inspect}"
-      assert_equal(expect, Liquid::Template.migrate(source), message)
-      assert_no_migration(expect)
-      assert_equal(Liquid::Template.parse(expect, parse_mode: :strict).render!, Liquid::Template.parse(source).render!, message)
-    end
-  end
-end

test/unit/parse_tree_visitor_test.rb

@@ -8,245 +8,245 @@ class ParseTreeVisitorTest < Minitest::Test
   def test_variable
     assert_equal(
       ["test"],
-      visit(%({{ test }}))
+      visit(%({{ test }})),
     )
   end
 
   def test_varible_with_filter
     assert_equal(
       ["test", "infilter"],
-      visit(%({{ test | split: infilter }}))
+      visit(%({{ test | split: infilter }})),
     )
   end
 
   def test_dynamic_variable
     assert_equal(
       ["test", "inlookup"],
-      visit(%({{ test[inlookup] }}))
+      visit(%({{ test[inlookup] }})),
     )
   end
 
   def test_echo
     assert_equal(
       ["test"],
-      visit(%({% echo test %}))
+      visit(%({% echo test %})),
     )
   end
 
   def test_if_condition
     assert_equal(
       ["test"],
-      visit(%({% if test %}{% endif %}))
+      visit(%({% if test %}{% endif %})),
     )
   end
 
   def test_complex_if_condition
     assert_equal(
       ["test"],
-      visit(%({% if 1 == 1 and 2 == test %}{% endif %}))
+      visit(%({% if 1 == 1 and 2 == test %}{% endif %})),
     )
   end
 
   def test_if_body
     assert_equal(
       ["test"],
-      visit(%({% if 1 == 1 %}{{ test }}{% endif %}))
+      visit(%({% if 1 == 1 %}{{ test }}{% endif %})),
     )
   end
 
   def test_unless_condition
     assert_equal(
       ["test"],
-      visit(%({% unless test %}{% endunless %}))
+      visit(%({% unless test %}{% endunless %})),
     )
   end
 
   def test_complex_unless_condition
     assert_equal(
       ["test"],
-      visit(%({% unless 1 == 1 and 2 == test %}{% endunless %}))
+      visit(%({% unless 1 == 1 and 2 == test %}{% endunless %})),
     )
   end
 
   def test_unless_body
     assert_equal(
       ["test"],
-      visit(%({% unless 1 == 1 %}{{ test }}{% endunless %}))
+      visit(%({% unless 1 == 1 %}{{ test }}{% endunless %})),
     )
   end
 
   def test_elsif_condition
     assert_equal(
       ["test"],
-      visit(%({% if 1 == 1 %}{% elsif test %}{% endif %}))
+      visit(%({% if 1 == 1 %}{% elsif test %}{% endif %})),
     )
   end
 
   def test_complex_elsif_condition
     assert_equal(
       ["test"],
-      visit(%({% if 1 == 1 %}{% elsif 1 == 1 and 2 == test %}{% endif %}))
+      visit(%({% if 1 == 1 %}{% elsif 1 == 1 and 2 == test %}{% endif %})),
     )
   end
 
   def test_elsif_body
     assert_equal(
       ["test"],
-      visit(%({% if 1 == 1 %}{% elsif 2 == 2 %}{{ test }}{% endif %}))
+      visit(%({% if 1 == 1 %}{% elsif 2 == 2 %}{{ test }}{% endif %})),
     )
   end
 
   def test_else_body
     assert_equal(
       ["test"],
-      visit(%({% if 1 == 1 %}{% else %}{{ test }}{% endif %}))
+      visit(%({% if 1 == 1 %}{% else %}{{ test }}{% endif %})),
     )
   end
 
   def test_case_left
     assert_equal(
       ["test"],
-      visit(%({% case test %}{% endcase %}))
+      visit(%({% case test %}{% endcase %})),
     )
   end
 
   def test_case_condition
     assert_equal(
       ["test"],
-      visit(%({% case 1 %}{% when test %}{% endcase %}))
+      visit(%({% case 1 %}{% when test %}{% endcase %})),
     )
   end
 
   def test_case_when_body
     assert_equal(
       ["test"],
-      visit(%({% case 1 %}{% when 2 %}{{ test }}{% endcase %}))
+      visit(%({% case 1 %}{% when 2 %}{{ test }}{% endcase %})),
     )
   end
 
   def test_case_else_body
     assert_equal(
       ["test"],
-      visit(%({% case 1 %}{% else %}{{ test }}{% endcase %}))
+      visit(%({% case 1 %}{% else %}{{ test }}{% endcase %})),
     )
   end
 
   def test_for_in
     assert_equal(
       ["test"],
-      visit(%({% for x in test %}{% endfor %}))
+      visit(%({% for x in test %}{% endfor %})),
     )
   end
 
   def test_for_limit
     assert_equal(
       ["test"],
-      visit(%({% for x in (1..5) limit: test %}{% endfor %}))
+      visit(%({% for x in (1..5) limit: test %}{% endfor %})),
     )
   end
 
   def test_for_offset
     assert_equal(
       ["test"],
-      visit(%({% for x in (1..5) offset: test %}{% endfor %}))
+      visit(%({% for x in (1..5) offset: test %}{% endfor %})),
     )
   end
 
   def test_for_body
     assert_equal(
       ["test"],
-      visit(%({% for x in (1..5) %}{{ test }}{% endfor %}))
+      visit(%({% for x in (1..5) %}{{ test }}{% endfor %})),
     )
   end
 
   def test_for_range
     assert_equal(
       ["test"],
-      visit(%({% for x in (1..test) %}{% endfor %}))
+      visit(%({% for x in (1..test) %}{% endfor %})),
     )
   end
 
   def test_tablerow_in
     assert_equal(
       ["test"],
-      visit(%({% tablerow x in test %}{% endtablerow %}))
+      visit(%({% tablerow x in test %}{% endtablerow %})),
     )
   end
 
   def test_tablerow_limit
     assert_equal(
       ["test"],
-      visit(%({% tablerow x in (1..5) limit: test %}{% endtablerow %}))
+      visit(%({% tablerow x in (1..5) limit: test %}{% endtablerow %})),
     )
   end
 
   def test_tablerow_offset
     assert_equal(
       ["test"],
-      visit(%({% tablerow x in (1..5) offset: test %}{% endtablerow %}))
+      visit(%({% tablerow x in (1..5) offset: test %}{% endtablerow %})),
     )
   end
 
   def test_tablerow_body
     assert_equal(
       ["test"],
-      visit(%({% tablerow x in (1..5) %}{{ test }}{% endtablerow %}))
+      visit(%({% tablerow x in (1..5) %}{{ test }}{% endtablerow %})),
     )
   end
 
   def test_cycle
     assert_equal(
       ["test"],
-      visit(%({% cycle test %}))
+      visit(%({% cycle test %})),
     )
   end
 
   def test_assign
     assert_equal(
       ["test"],
-      visit(%({% assign x = test %}))
+      visit(%({% assign x = test %})),
     )
   end
 
   def test_capture
     assert_equal(
       ["test"],
-      visit(%({% capture x %}{{ test }}{% endcapture %}))
+      visit(%({% capture x %}{{ test }}{% endcapture %})),
     )
   end
 
   def test_include
     assert_equal(
       ["test"],
-      visit(%({% include test %}))
+      visit(%({% include test %})),
     )
   end
 
   def test_include_with
     assert_equal(
       ["test"],
-      visit(%({% include "hai" with test %}))
+      visit(%({% include "hai" with test %})),
     )
   end
 
   def test_include_for
     assert_equal(
       ["test"],
-      visit(%({% include "hai" for test %}))
+      visit(%({% include "hai" for test %})),
     )
   end
 
   def test_render_with
     assert_equal(
       ["test"],
-      visit(%({% render "hai" with test %}))
+      visit(%({% render "hai" with test %})),
     )
   end
 
   def test_render_for
     assert_equal(
       ["test"],
-      visit(%({% render "hai" for test %}))
+      visit(%({% render "hai" for test %})),
     )
   end
 
@@ -257,7 +257,7 @@ class ParseTreeVisitorTest < Minitest::Test
         ["test", []],
         ["xs", []],
       ]]],
-      traversal(%({% for x in xs offset: test %}{{ other }}{% endfor %})).visit
+      traversal(%({% for x in xs offset: test %}{{ other }}{% endfor %})).visit,
     )
   end
 

test/unit/partial_cache_unit_test.rb

@@ -7,13 +7,13 @@ class PartialCacheUnitTest < Minitest::Test
     context = Liquid::Context.build(
       registers: {
         file_system: StubFileSystem.new('my_partial' => 'my partial body'),
-      }
+      },
     )
 
     partial = Liquid::PartialCache.load(
       'my_partial',
       context: context,
-      parse_context: Liquid::ParseContext.new
+      parse_context: Liquid::ParseContext.new,
     )
 
     assert_equal('my partial body', partial.render)
@@ -22,14 +22,14 @@ class PartialCacheUnitTest < Minitest::Test
   def test_reads_from_the_file_system_only_once_per_file
     file_system = StubFileSystem.new('my_partial' => 'some partial body')
     context     = Liquid::Context.build(
-      registers: { file_system: file_system }
+      registers: { file_system: file_system },
     )
 
     2.times do
       Liquid::PartialCache.load(
         'my_partial',
         context: context,
-        parse_context: Liquid::ParseContext.new
+        parse_context: Liquid::ParseContext.new,
       )
     end
 
@@ -39,31 +39,31 @@ class PartialCacheUnitTest < Minitest::Test
   def test_cache_state_is_stored_per_context
     parse_context      = Liquid::ParseContext.new
     shared_file_system = StubFileSystem.new(
-      'my_partial' => 'my shared value'
+      'my_partial' => 'my shared value',
     )
     context_one = Liquid::Context.build(
       registers: {
         file_system: shared_file_system,
-      }
+      },
     )
     context_two = Liquid::Context.build(
       registers: {
         file_system: shared_file_system,
-      }
+      },
     )
 
     2.times do
       Liquid::PartialCache.load(
         'my_partial',
         context: context_one,
-        parse_context: parse_context
+        parse_context: parse_context,
       )
     end
 
     Liquid::PartialCache.load(
       'my_partial',
       context: context_two,
-      parse_context: parse_context
+      parse_context: parse_context,
     )
 
     assert_equal(2, shared_file_system.file_read_count)
@@ -72,18 +72,18 @@ class PartialCacheUnitTest < Minitest::Test
   def test_cache_is_not_broken_when_a_different_parse_context_is_used
     file_system = StubFileSystem.new('my_partial' => 'some partial body')
     context     = Liquid::Context.build(
-      registers: { file_system: file_system }
+      registers: { file_system: file_system },
     )
 
     Liquid::PartialCache.load(
       'my_partial',
       context: context,
-      parse_context: Liquid::ParseContext.new(my_key: 'value one')
+      parse_context: Liquid::ParseContext.new(my_key: 'value one'),
     )
     Liquid::PartialCache.load(
       'my_partial',
       context: context,
-      parse_context: Liquid::ParseContext.new(my_key: 'value two')
+      parse_context: Liquid::ParseContext.new(my_key: 'value two'),
     )
 
     # Technically what we care about is that the file was parsed twice,
@@ -95,13 +95,13 @@ class PartialCacheUnitTest < Minitest::Test
     context = Liquid::Context.build(
       registers: {
         file_system: StubFileSystem.new('my_partial' => 'my partial body'),
-      }
+      },
     )
 
     partial = Liquid::PartialCache.load(
       'my_partial',
       context: context,
-      parse_context: Liquid::ParseContext.new
+      parse_context: Liquid::ParseContext.new,
     )
 
     assert_equal('my partial body', partial.render)
@@ -113,13 +113,13 @@ class PartialCacheUnitTest < Minitest::Test
       registers: {
         file_system: StubFileSystem.new('my_partial' => 'my partial body'),
         template_factory: template_factory,
-      }
+      },
     )
 
     partial = Liquid::PartialCache.load(
       'my_partial',
       context: context,
-      parse_context: Liquid::ParseContext.new
+      parse_context: Liquid::ParseContext.new,
     )
 
     assert_equal('my partial body', partial.render)
@@ -129,12 +129,12 @@ class PartialCacheUnitTest < Minitest::Test
   def test_cache_state_is_shared_for_subcontexts
     parse_context      = Liquid::ParseContext.new
     shared_file_system = StubFileSystem.new(
-      'my_partial' => 'my shared value'
+      'my_partial' => 'my shared value',
     )
     context = Liquid::Context.build(
       registers: Liquid::Registers.new(
         file_system: shared_file_system,
-      )
+      ),
     )
     subcontext = context.new_isolated_subcontext
 
@@ -144,16 +144,57 @@ class PartialCacheUnitTest < Minitest::Test
       Liquid::PartialCache.load(
         'my_partial',
         context: context,
-        parse_context: parse_context
+        parse_context: parse_context,
       )
 
       Liquid::PartialCache.load(
         'my_partial',
         context: subcontext,
-        parse_context: parse_context
+        parse_context: parse_context,
       )
     end
 
     assert_equal(1, shared_file_system.file_read_count)
   end
+
+  def test_uses_template_name_from_template_factory
+    template_factory = StubTemplateFactory.new
+    context = Liquid::Context.build(
+      registers: {
+        file_system: StubFileSystem.new('my_partial' => 'my partial body'),
+        template_factory: template_factory,
+      },
+    )
+
+    partial = Liquid::PartialCache.load(
+      'my_partial',
+      context: context,
+      parse_context: Liquid::ParseContext.new,
+    )
+
+    assert_equal('some/path/my_partial', partial.name)
+  end
+
+  def test_includes_error_mode_into_template_cache
+    template_factory = StubTemplateFactory.new
+    context = Liquid::Context.build(
+      registers: {
+        file_system: StubFileSystem.new('my_partial' => 'my partial body'),
+        template_factory: template_factory,
+      },
+    )
+
+    [:lax, :warn, :strict].each do |error_mode|
+      Liquid::PartialCache.load(
+        'my_partial',
+        context: context,
+        parse_context: Liquid::ParseContext.new(error_mode: error_mode),
+      )
+    end
+
+    assert_equal(
+      ["my_partial:lax", "my_partial:warn", "my_partial:strict"],
+      context.registers[:cached_partials].keys,
+    )
+  end
 end

test/unit/regexp_unit_test.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'test_helper'
+require 'timeout'
 
 class RegexpUnitTest < Minitest::Test
   include Liquid
@@ -37,10 +38,22 @@ class RegexpUnitTest < Minitest::Test
 
   def test_variable_parser
     assert_equal(['var'],                               'var'.scan(VariableParser))
+    assert_equal(['[var]'],                             '[var]'.scan(VariableParser))
     assert_equal(['var', 'method'],                     'var.method'.scan(VariableParser))
     assert_equal(['var', '[method]'],                   'var[method]'.scan(VariableParser))
     assert_equal(['var', '[method]', '[0]'],            'var[method][0]'.scan(VariableParser))
     assert_equal(['var', '["method"]', '[0]'],          'var["method"][0]'.scan(VariableParser))
     assert_equal(['var', '[method]', '[0]', 'method'],  'var[method][0].method'.scan(VariableParser))
   end
+
+  def test_variable_parser_with_large_input
+    Timeout.timeout(1) { assert_equal(['[var]'], '[var]'.scan(VariableParser)) }
+
+    very_long_string = "foo" * 1000
+
+    # valid dynamic lookup
+    Timeout.timeout(1) { assert_equal(["[#{very_long_string}]"], "[#{very_long_string}]".scan(VariableParser)) }
+    # invalid dynamic lookup with missing closing bracket
+    Timeout.timeout(1) { assert_equal([very_long_string], "[#{very_long_string}".scan(VariableParser)) }
+  end
 end # RegexpTest

test/unit/strainer_template_unit_test.rb

@@ -25,11 +25,13 @@ class StrainerTemplateUnitTest < Minitest::Test
   end
 
   def test_add_filter_raises_when_module_privately_overrides_registered_public_methods
-    strainer = Context.new.strainer
-
     error = assert_raises(Liquid::MethodOverrideError) do
-      strainer.class.add_filter(PrivateMethodOverrideFilter)
+      Liquid::Environment.build do |env|
+        env.register_filter(PublicMethodOverrideFilter)
+        env.register_filter(PrivateMethodOverrideFilter)
+      end
     end
+
     assert_equal('Liquid error: Filter overrides registered public methods as non public: public_filter', error.message)
   end
 
@@ -42,11 +44,13 @@ class StrainerTemplateUnitTest < Minitest::Test
   end
 
   def test_add_filter_raises_when_module_overrides_registered_public_method_as_protected
-    strainer = Context.new.strainer
-
     error = assert_raises(Liquid::MethodOverrideError) do
-      strainer.class.add_filter(ProtectedMethodOverrideFilter)
+      Liquid::Environment.build do |env|
+        env.register_filter(PublicMethodOverrideFilter)
+        env.register_filter(ProtectedMethodOverrideFilter)
+      end
     end
+
     assert_equal('Liquid error: Filter overrides registered public methods as non public: public_filter', error.message)
   end
 
@@ -58,8 +62,9 @@ class StrainerTemplateUnitTest < Minitest::Test
 
   def test_add_filter_does_not_raise_when_module_overrides_previously_registered_method
     with_global_filter do
-      strainer = Context.new.strainer
-      strainer.class.add_filter(PublicMethodOverrideFilter)
+      context = Context.new
+      context.add_filters([PublicMethodOverrideFilter])
+      strainer = context.strainer
       assert(strainer.class.send(:filter_methods).include?('public_filter'))
     end
   end

test/unit/tag_unit_test.rb

@@ -20,4 +20,13 @@ class TagUnitTest < Minitest::Test
     tag = Tag.parse("some_tag", "", Tokenizer.new(""), ParseContext.new)
     assert_equal('some_tag', tag.tag_name)
   end
+
+  class CustomTag < Liquid::Tag
+    def render(_context); end
+  end
+
+  def test_tag_render_to_output_buffer_nil_value
+    custom_tag = CustomTag.parse("some_tag", "", Tokenizer.new(""), ParseContext.new)
+    assert_equal('some string', custom_tag.render_to_output_buffer(Context.new, "some string"))
+  end
 end

test/unit/tags/comment_tag_unit_test.rb

@@ -0,0 +1,202 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class CommentTagUnitTest < Minitest::Test
+  def test_comment_inside_liquid_tag
+    assert_template_result("", <<~LIQUID.chomp)
+      {% liquid
+        if 1 != 1
+        comment
+        else
+          echo 123
+        endcomment
+        endif
+      %}
+    LIQUID
+  end
+
+  def test_does_not_parse_nodes_inside_a_comment
+    assert_template_result("", <<~LIQUID.chomp)
+      {% comment %}
+        {% if true %}
+        {% if ... %}
+        {%- for ? -%}
+        {% while true %}
+        {%
+          unless if
+        %}
+        {% endcase %}
+      {% endcomment %}
+    LIQUID
+  end
+
+  def test_allows_unclosed_tags
+    assert_template_result('', <<~LIQUID.chomp)
+      {% comment %}
+        {% if true %}
+      {% endcomment %}
+    LIQUID
+  end
+
+  def test_open_tags_in_comment
+    assert_template_result('', <<~LIQUID.chomp)
+      {% comment %}
+        {% assign a = 123 {% comment %}
+      {% endcomment %}
+    LIQUID
+
+    assert_raises(Liquid::SyntaxError) do
+      assert_template_result("", <<~LIQUID.chomp)
+        {% comment %}
+          {% assign foo = "1"
+        {% endcomment %}
+      LIQUID
+    end
+
+    assert_raises(Liquid::SyntaxError) do
+      assert_template_result("", <<~LIQUID.chomp)
+        {% comment %}
+          {% comment %}
+            {% invalid
+          {% endcomment %}
+        {% endcomment %}
+      LIQUID
+    end
+
+    assert_raises(Liquid::SyntaxError) do
+      assert_template_result("", <<~LIQUID.chomp)
+        {% comment %}
+        {% {{ {%- endcomment %}
+      LIQUID
+    end
+  end
+
+  def test_child_comment_tags_need_to_be_closed
+    assert_template_result("", <<~LIQUID.chomp)
+      {% comment %}
+        {% comment %}
+          {% comment %}{%    endcomment     %}
+        {% endcomment %}
+      {% endcomment %}
+    LIQUID
+
+    assert_raises(Liquid::SyntaxError) do
+      assert_template_result("", <<~LIQUID.chomp)
+        {% comment %}
+          {% comment %}
+            {% comment %}
+          {% endcomment %}
+        {% endcomment %}
+      LIQUID
+    end
+  end
+
+  def test_child_raw_tags_need_to_be_closed
+    assert_template_result("", <<~LIQUID.chomp)
+      {% comment %}
+        {% raw %}
+          {% endcomment %}
+        {% endraw %}
+      {% endcomment %}
+    LIQUID
+
+    assert_raises(Liquid::SyntaxError) do
+      Liquid::Template.parse(<<~LIQUID.chomp)
+        {% comment %}
+          {% raw %}
+          {% endcomment %}
+        {% endcomment %}
+      LIQUID
+    end
+  end
+
+  def test_error_line_number_is_correct
+    template = Liquid::Template.parse(<<~LIQUID.chomp, line_numbers: true)
+      {% comment %}
+        {% if true %}
+      {% endcomment %}
+      {{ errors.standard_error }}
+    LIQUID
+
+    output = template.render('errors' => ErrorDrop.new)
+    expected = <<~TEXT.chomp
+
+      Liquid error (line 4): standard error
+    TEXT
+
+    assert_equal(expected, output)
+  end
+
+  def test_comment_tag_delimiter_with_extra_strings
+    assert_template_result(
+      '',
+      <<~LIQUID.chomp,
+        {% comment %}
+          {% comment %}
+          {% endcomment
+          {% if true %}
+          {% endif %}
+        {% endcomment %}
+      LIQUID
+    )
+  end
+
+  def test_nested_comment_tag_with_extra_strings
+    assert_template_result(
+      '',
+      <<~LIQUID.chomp,
+        {% comment %}
+          {% comment
+            {% assign foo = 1 %}
+          {% endcomment
+          {% assign foo = 1 %}
+        {% endcomment %}
+      LIQUID
+    )
+  end
+
+  def test_ignores_delimiter_with_extra_strings
+    assert_template_result(
+      '',
+      <<~LIQUID.chomp,
+        {% if true %}
+          {% comment %}
+            {% commentXXXXX %}wut{% endcommentXXXXX %}
+          {% endcomment %}
+        {% endif %}
+      LIQUID
+    )
+  end
+
+  def test_delimiter_can_have_extra_strings
+    assert_template_result('', "{% comment %}123{% endcomment xyz %}")
+    assert_template_result('', "{% comment %}123{% endcomment\txyz %}")
+    assert_template_result('', "{% comment %}123{% endcomment\nxyz %}")
+    assert_template_result('', "{% comment %}123{% endcomment\n   xyz  endcomment %}")
+    assert_template_result('', "{%comment}{% assign a = 1 %}{%endcomment}{% endif %}")
+  end
+
+  def test_with_whitespace_control
+    assert_template_result("Hello!", "      {%- comment -%}123{%- endcomment -%}Hello!")
+    assert_template_result("Hello!", "{%- comment -%}123{%- endcomment -%}     Hello!")
+    assert_template_result("Hello!", "      {%- comment -%}123{%- endcomment -%}     Hello!")
+
+    assert_template_result("Hello!", <<~LIQUID.chomp)
+      {%- comment %}Whitespace control!{% endcomment -%}
+      Hello!
+    LIQUID
+  end
+
+  def test_dont_override_liquid_tag_whitespace_control
+    assert_template_result("Hello!World!", <<~LIQUID.chomp)
+      Hello!
+      {%- liquid
+        comment
+         this is inside a liquid tag
+        endcomment
+      -%}
+      World!
+    LIQUID
+  end
+end