use byteslice to create Variable BlockBody

* Speed up lexing

* Bump msrv to 3.0 (from 2.7)

* Normalize test for ruby-head compat

* Fix bug when parsing negative numbers

.github/workflows/liquid.yml

@@ -11,10 +11,10 @@ jobs:
     strategy:
       matrix:
         entry:
-          - { ruby: 2.7, allowed-failure: false } # minimum supported
+          - { 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: true }
+          - { ruby: ruby-head, allowed-failure: false }
     name: Test Ruby ${{ matrix.entry.ruby }}
     steps:
       - uses: actions/checkout@v3

.gitignore

@@ -6,3 +6,4 @@ pkg
 .rvmrc
 .bundle
 .byebug_history
+Gemfile.lock

.ruby-version

@@ -1 +1 @@
-3.3.0
+3.3.4

Gemfile

@@ -7,6 +7,8 @@ end
 
 gemspec
 
+gem "base64"
+
 group :benchmark, :test do
   gem 'benchmark-ips'
   gem 'memory_profiler'
@@ -26,7 +28,3 @@ group :test do
     gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'main'
   end
 end
-
-gem "vernier", "~> 1.0"
-
-gem "debug", "~> 1.9"

Gemfile.lock

@@ -1,90 +0,0 @@
-GIT
-  remote: https://github.com/Shopify/liquid-c.git
-  revision: 5a786af7284df55e013ea20551c4b688d02e8326
-  ref: main
-  specs:
-    liquid-c (4.2.0)
-      liquid (>= 5.0.1)
-
-PATH
-  remote: .
-  specs:
-    liquid (5.5.0)
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    ast (2.4.2)
-    benchmark-ips (2.13.0)
-    debug (1.9.2)
-      irb (~> 1.10)
-      reline (>= 0.3.8)
-    io-console (0.7.2)
-    irb (1.13.1)
-      rdoc (>= 4.0.0)
-      reline (>= 0.4.2)
-    json (2.7.2)
-    language_server-protocol (3.17.0.3)
-    memory_profiler (1.0.1)
-    minitest (5.22.3)
-    parallel (1.24.0)
-    parser (3.3.0.5)
-      ast (~> 2.4.1)
-      racc
-    psych (5.1.2)
-      stringio
-    racc (1.7.3)
-    rainbow (3.1.1)
-    rake (13.2.1)
-    rdoc (6.7.0)
-      psych (>= 4.0.0)
-    regexp_parser (2.9.0)
-    reline (0.5.8)
-      io-console (~> 0.5)
-    rexml (3.2.6)
-    rubocop (1.61.0)
-      json (~> 2.3)
-      language_server-protocol (>= 3.17.0)
-      parallel (~> 1.10)
-      parser (>= 3.3.0.2)
-      rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.8, < 3.0)
-      rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.30.0, < 2.0)
-      ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.31.2)
-      parser (>= 3.3.0.4)
-    rubocop-performance (1.19.1)
-      rubocop (>= 1.7.0, < 2.0)
-      rubocop-ast (>= 0.4.0)
-    rubocop-shopify (2.12.0)
-      rubocop (~> 1.44)
-    ruby-progressbar (1.13.0)
-    stackprof (0.2.26)
-    stringio (3.1.0)
-    terminal-table (3.0.2)
-      unicode-display_width (>= 1.1.1, < 3)
-    unicode-display_width (2.5.0)
-    vernier (1.0.1)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  benchmark-ips
-  debug (~> 1.9)
-  liquid!
-  liquid-c!
-  memory_profiler
-  minitest
-  rake (~> 13.0)
-  rubocop (~> 1.61.0)
-  rubocop-performance
-  rubocop-shopify (~> 2.12.0)
-  stackprof
-  terminal-table
-  vernier (~> 1.0)
-
-BUNDLED WITH
-   2.5.7

README.md

@@ -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`:

Rakefile

@@ -81,6 +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/liquid2profile

@@ -1,96 +0,0 @@
-#!/usr/bin/env ruby
-# frozen_string_literal: true
-
-require "bundler/setup"
-require "optparse"
-
-if %x(which samply).empty?
-  print "samply is not installed. Would you like to install it? [y/n] "
-  answer = $stdin.gets.chomp
-  if answer.downcase == "y"
-    puts "Installing samply..."
-    system("cargo install --git https://github.com/mstange/samply samply")
-  else
-    puts "samply is required for this script to run. Exiting..."
-    exit
-  end
-end
-
-options = {
-  db: File.expand_path("../bench/benchmarks/basic/db.yml", __dir__),
-  n_runs: 50000,
-  samply_run: true,
-  yjit_perfmap: false,
-  samply_output: "profile.json",
-  vernier: false,
-}
-
-optparse = OptionParser.new do |opts|
-  opts.on("--db [DB]", "use the provided db file instead of the default") do |db|
-    options[:db] = db
-  end
-  opts.on("-n [N]", "number of runs") do |n|
-    options[:n_runs] = n.to_i
-  end
-  opts.on("--skip-samply-run", "skip running samply") do
-    options[:samply_run] = false
-  end
-  opts.on("--yjit-perfmap", "enable yjit perfmap") do
-    options[:yjit_perfmap] = true
-  end
-  opts.on("--samply-output [OUTPUT]", "output file for samply") do |output|
-    options[:samply_output] = output
-  end
-  opts.on("--vernier", "enable vernier") do
-    options[:vernier] = true
-  end
-end
-optparse.parse!
-
-if options[:samply_run] && !options[:vernier]
-  samply_output = options[:samply_output]
-  if options[:yjit_perfmap]
-    exec(
-      "samply",
-      "record",
-      "--output",
-      samply_output,
-      "ruby",
-      "--yjit",
-      "--yjit-perf",
-      __FILE__,
-      "--skip-samply-run",
-      *ARGV,
-    )
-  else
-    exec("samply", "record", "--output", samply_output, "bundle", "exec", __FILE__, "--skip-samply-run", *ARGV)
-  end
-end
-
-lib = File.expand_path("../lib", __dir__)
-$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
-
-n_runs = options[:n_runs]
-code = ARGF.read
-
-require "liquid"
-# require "liquid/c"
-
-cpu_time_start = Process.clock_gettime(Process::CLOCK_PROCESS_CPUTIME_ID)
-
-if options[:vernier]
-  require "vernier"
-  Vernier.trace(out: "profile.json") do
-    n_runs.times do
-      Liquid::Template.parse(code)
-    end
-  end
-else
-  n_runs.times do
-    Liquid::Template.parse(code)
-  end
-end
-
-cpu_time_end = Process.clock_gettime(Process::CLOCK_PROCESS_CPUTIME_ID)
-cpu_time = cpu_time_end - cpu_time_start
-puts "CPU time: #{cpu_time}"

lib/liquid.rb

@@ -49,9 +49,19 @@ module Liquid
   self.cache_classes = true
 end
 
-require "debug"
 require "liquid/version"
+require "liquid/deprecations"
+require "liquid/const"
+require "liquid/template/tag_registry"
+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'
@@ -63,22 +73,16 @@ require 'liquid/errors'
 require 'liquid/interrupts'
 require 'liquid/strainer_template'
 require 'liquid/strainer_factory'
-require 'liquid/parser_switching'
 require 'liquid/expression'
 require 'liquid/context'
 require 'liquid/tag'
-require 'liquid/tag/disabler'
-require 'liquid/tag/disableable'
-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'
@@ -87,7 +91,3 @@ 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_body.rb

@@ -52,7 +52,7 @@ module Liquid
             next parse_liquid_tag(markup, parse_context)
           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
@@ -147,7 +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
@@ -247,11 +247,16 @@ module Liquid
 
     def create_variable(token, parse_context)
       if token.end_with?("}}")
-        start_markup = token[2] == WhitespaceControl ? 3 : 2
-        end_markup = token[-3] == WhitespaceControl ? -3 : -2
-        markup = token[start_markup...end_markup]
+        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.byteslice(i, markup_end)
+
         return Variable.new(markup, parse_context)
       end
+
       BlockBody.raise_missing_variable_terminator(token, parse_context)
     end
 
@@ -264,9 +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/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

@@ -15,14 +15,15 @@ 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)
+    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, &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!
 
@@ -32,7 +33,7 @@ module Liquid
       @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.

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/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 = Template::TagRegistry.new(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 = Template::TagRegistry.new(Tags::STANDARD_TAGS)
+      @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/expression.rb

@@ -20,31 +20,7 @@ module Liquid
     # malicious input as described in https://github.com/Shopify/liquid/issues/1357
     RANGES_REGEX         = /\A\(\s*(?>(\S+)\s*\.\.)\s*(\S+)\s*\)\z/
 
-    include ParserSwitching
-
-    def self.parse(markup, parse_context)
-      new(markup, parse_context)
-    end
-
-    private_class_method def self.new(markup, parse_context)
-      obj = allocate
-      obj.instance_variable_set(:@markup, markup)
-      obj.instance_variable_set(:@parse_context, parse_context)
-      if !parse_context.nil?
-        obj.strict_parse_with_error_mode_fallback(markup)
-      else
-        obj.lax_parse(markup)
-      end
-    end
-
-    def strict_parse(markup)
-      return nil unless markup
-
-      p = Parser.new(markup)
-      p.expression
-    end
-
-    def lax_parse(markup)
+    def self.parse(markup)
       return nil unless markup
 
       markup = markup.strip
@@ -57,7 +33,7 @@ module Liquid
       when INTEGERS_REGEX
         Regexp.last_match(1).to_i
       when RANGES_REGEX
-        RangeLookup.parse(Regexp.last_match(1), Regexp.last_match(2), parse_context)
+        RangeLookup.parse(Regexp.last_match(1), Regexp.last_match(2))
       when FLOATS_REGEX
         Regexp.last_match(1).to_f
       else

lib/liquid/lexer.rb

@@ -1,183 +1,215 @@
 # frozen_string_literal: true
 
+require "strscan"
+
 module Liquid
-  class StringScanner
-    def initialize(string)
-      @len = string.length
-      @string = string.freeze
-      @buffer = IO::Buffer.for(@string)
-      @pos    = 0
-    end
-
-    def eos?
-      @pos >= @len
-    end
-
-    def peek(n = 0)
-      return if @pos + n >= @len
-      @buffer.get_value(:U8, @pos + n)
-    end
-
-    def match(str)
-      return if @pos + str.length > @len
-
-      if (@buffer.slice(@pos, str.length) <=> IO::Buffer.for(str)) == 0
-        advance(str.length)
-      end
-    end
-
-    def match_until(char)
-      pos = 1
-      pos += 1 while peek(pos) != char
-      if peek(pos) == char
-        advance(pos + 1)
-      end
-    end
-
-    def advance(n = 1)
-      original_pos = @pos
-      @pos += n
-      @string[original_pos, n]
-    end
-
-    def space?(c)
-      return false unless c
-      c == 32 || c == 9 || c == 10 || c == 13
-    end
-
-    def skip_spaces
-      @pos += 1 while @pos < @len && space?(@buffer.get_value(:U8, @pos))
-    end
-  end
-
-  class Lexer
+  class Lexer1
     SPECIALS = {
-      '|'.ord => :pipe,
-      '.'.ord => :dot,
-      ':'.ord => :colon,
-      ','.ord => :comma,
-      '['.ord => :open_square,
-      ']'.ord => :close_square,
-      '('.ord => :open_round,
-      ')'.ord => :close_round,
-      '?'.ord => :question,
-      '-'.ord => :dash,
+      '|' => :pipe,
+      '.' => :dot,
+      ':' => :colon,
+      ',' => :comma,
+      '[' => :open_square,
+      ']' => :close_square,
+      '(' => :open_round,
+      ')' => :close_round,
+      '?' => :question,
+      '-' => :dash,
     }.freeze
-
-    LESS_THAN = '<'.ord
-    GREATER_THAN = '>'.ord
-    EQUALS = '='.ord
-    EXCLAMATION = '!'.ord
-    QUOTE = '"'.ord
-    APOSTROPHE = "'".ord
-    DASH = '-'.ord
-    DOT = '.'.ord
-    UNDERSCORE = '_'.ord
-    QUESTION_MARK = '?'.ord
+    IDENTIFIER            = /[a-zA-Z_][\w-]*\??/
+    SINGLE_STRING_LITERAL = /'[^\']*'/
+    DOUBLE_STRING_LITERAL = /"[^\"]*"/
+    STRING_LITERAL        = Regexp.union(SINGLE_STRING_LITERAL, DOUBLE_STRING_LITERAL)
+    NUMBER_LITERAL        = /-?\d+(\.\d+)?/
+    DOTDOT                = /\.\./
+    COMPARISON_OPERATOR   = /==|!=|<>|<=?|>=?|contains(?=\s)/
+    WHITESPACE_OR_NOTHING = /\s*/
 
     def initialize(input)
       @ss = StringScanner.new(input)
     end
 
-    def digit?(char)
-      return false unless char
-      char >= 48 && char <= 57
-    end
-
-    def alpha?(char)
-      return false unless char
-      char >= 65 && char <= 90 || char >= 97 && char <= 122
-    end
-
-    def identifier?(char)
-      return false unless char
-      digit?(char) || alpha?(char) || char == UNDERSCORE || char == DASH
-    end
-
     def tokenize
       @output = []
 
       until @ss.eos?
-        @ss.skip_spaces
+        @ss.skip(WHITESPACE_OR_NOTHING)
         break if @ss.eos?
-
-        next_char = @ss.peek
-        case next_char
-        when LESS_THAN
-          @output << [:comparison, @ss.match("<=") || @ss.match("<>") || @ss.match("<")]
-          next
-        when GREATER_THAN
-          @output << [:comparison, @ss.match(">=") || @ss.match(">")]
-          next
-        when EQUALS
-          if (match = @ss.match("=="))
-            @output << [:comparison, match]
-            next
-          end
-        when EXCLAMATION
-          if (match = @ss.match("!="))
-            @output << [:comparison, match]
-            next
-          end
-        when DOT
-          if (match = @ss.match(".."))
-            @output << [:dotdot, match]
-            next
-          end
-        end
-
-        if (match = @ss.match("contains"))
-          @output << [:comparison, match]
-          next
-        end
-
-        if next_char == APOSTROPHE || next_char == QUOTE
-          if (str = @ss.match_until(next_char))
-            @output << [:string, str]
-            next
-          end
-        end
-
-        if next_char == DASH || digit?(next_char)
-          peek = 1
-          has_dot = false
-          while (peeked = @ss.peek(peek))
-            if !has_dot && peeked == DOT
-              has_dot = true
-            elsif !digit?(peeked)
-              break
-            end
-            peek += 1
-          end
-          peek -= 1
-
-          if @ss.peek(peek) == DOT
-            peek -= 1
-          end
-
-          if @ss.peek(peek) != DASH
-            @output << [:number, @ss.advance(peek)]
-            next
-          end
-        end
-
-        if alpha?(next_char) || next_char == UNDERSCORE
-          peek = 1
-          peek += 1 while identifier?(@ss.peek(peek))
-          peek += 1 if @ss.peek(peek) == QUESTION_MARK
-          @output << [:id, @ss.advance(peek)]
-          next
-        end
-
-        if (special = SPECIALS[next_char])
-          @output << [special, @ss.advance]
-          next
+        tok      = if (t = @ss.scan(COMPARISON_OPERATOR))
+          [:comparison, t]
+        elsif (t = @ss.scan(STRING_LITERAL))
+          [:string, t]
+        elsif (t = @ss.scan(NUMBER_LITERAL))
+          [:number, t]
+        elsif (t = @ss.scan(IDENTIFIER))
+          [:id, t]
+        elsif (t = @ss.scan(DOTDOT))
+          [:dotdot, t]
         else
-          raise SyntaxError, "Unexpected character #{next_char.chr}"
+          c     = @ss.getch
+          if (s = SPECIALS[c])
+            [s, c]
+          else
+            raise SyntaxError, "Unexpected character #{c}"
+          end
         end
+        @output << tok
       end
 
       @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
+    CONTAINS = /contains(?=\s)/
+    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*/
+
+    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
+      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?
+
+        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 NUMBER_TABLE[@ss.peek_byte]
+              @ss.pos -= 1
+              @output << [:number, @ss.scan(NUMBER_LITERAL)]
+            else
+              @output << special
+            end
+          else
+            @output << special
+          end
+        elsif (sub_table = COMPARISON_JUMP_TABLE[peeked])
+          @ss.scan_byte
+          if (found = sub_table[@ss.peek_byte])
+            @output << found
+            @ss.scan_byte
+          else
+            raise SyntaxError, "Unexpected character #{peeked.chr}"
+          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"
+              COMPARISON_CONTAINS
+            else
+              [type, t]
+            end
+          else
+            raise SyntaxError, "Unexpected character #{peeked.chr}"
+          end
+        end
+      end
+      # rubocop:enable Metrics/BlockNesting
+
+      @output << EOS
+    end
+  end
+
+  Lexer = StringScanner.instance_methods.include?(:scan_byte) ? Lexer2 : Lexer1
 end

lib/liquid/parse_context.rb

@@ -3,9 +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
 
-    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
@@ -28,14 +29,14 @@ module Liquid
     end
 
     def parse_expression(markup)
-      Expression.parse(markup, self)
+      Expression.parse(markup)
     end
 
     def partial=(value)
       @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/parser.rb

@@ -2,9 +2,6 @@
 
 module Liquid
   class Parser
-    Kwarg = Struct.new(:name, :value)
-    Arg = Struct.new(:value)
-
     def initialize(input)
       l       = Lexer.new(input)
       @tokens = l.tokenize
@@ -53,17 +50,10 @@ module Liquid
       token = @tokens[@p]
       case token[0]
       when :id
-        name = consume
-        lookups = variable_lookups
-        command_flags = 0
-        lookups.each_index do |i|
-          if VariableLookup::COMMAND_METHODS.include?(lookups[i])
-            @command_flags |= 1 << i
-          end
-        end
-        VariableLookup.new_with(name, lookups, command_flags)
-      when :open_square
         str = consume
+        str << variable_lookups
+      when :open_square
+        str = consume.dup
         str << expression
         str << consume(:close_square)
         str << variable_lookups
@@ -82,32 +72,31 @@ module Liquid
     end
 
     def argument
+      str = +""
       # might be a keyword argument (identifier: expression)
       if look(:id) && look(:colon, 1)
-        name = consume(:id)
-        consume(:colon)
-        value = expression
-        Kwarg.new(name, value)
-      else
-        Arg.new(expression)
+        str << consume << consume << ' '
       end
+
+      str << expression
+      str
     end
 
     def variable_lookups
-      lookups = []
+      str = +""
       loop do
         if look(:open_square)
-          consume
-          lookups << expression
-          consume(:close_square)
+          str << consume
+          str << expression
+          str << consume(:close_square)
         elsif look(:dot)
-          consume
-          lookups << consume(:id)
+          str << consume
+          str << consume(:id)
         else
           break
         end
       end
-      lookups
+      str
     end
   end
 end

lib/liquid/parser_switching.rb

@@ -33,7 +33,6 @@ module Liquid
     def strict_parse_with_error_context(markup)
       strict_parse(markup)
     rescue SyntaxError => e
-      puts e
       e.line_number    = line_number
       e.markup_context = markup_context(markup)
       raise e

lib/liquid/range_lookup.rb

@@ -2,9 +2,9 @@
 
 module Liquid
   class RangeLookup
-    def self.parse(start_markup, end_markup, parse_context = nil)
-      start_obj = Expression.parse(start_markup, parse_context)
-      end_obj   = Expression.parse(end_markup, parse_context)
+    def self.parse(start_markup, end_markup)
+      start_obj = Expression.parse(start_markup)
+      end_obj   = Expression.parse(end_markup)
       if start_obj.respond_to?(:evaluate) || end_obj.respond_to?(:evaluate)
         new(start_obj, end_obj)
       else

lib/liquid/standardfilters.rb

@@ -1001,6 +1001,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_filter(StandardFilters)
 end

lib/liquid/strainer_factory.rb

@@ -5,37 +5,19 @@ module Liquid
   module StrainerFactory
     extend self
 
-    def add_global_filter(filter)
-      strainer_class_cache.clear
-      GlobalCache.add_filter(filter)
+    def add_global_filter(filter, environment = Environment.default)
+      Deprecations.warn("StrainerFactory.add_global_filter", "Environment#register_filter")
+      environment.register_filter(filter)
     end
 
-    def create(context, filters = [])
-      strainer_from_cache(filters).new(context)
+    def create(context, filters = Const::EMPTY_ARRAY, environment = Environment.default)
+      Deprecations.warn("StrainerFactory.create", "StrainerFactory.create_strainer")
+      environment.create_strainer(context, filters)
     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 ||= {}
+    def global_filter_names(environment = Environment.default)
+      Deprecations.warn("StrainerFactory.global_filter_names", "Environment#filter_method_names")
+      Environment.strainer_template.filter_method_names
     end
   end
 end

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

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

@@ -72,6 +72,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('assign', Assign)
 end

lib/liquid/tags/break.rb

@@ -26,6 +26,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('break', Break)
 end

lib/liquid/tags/capture.rb

@@ -39,6 +39,4 @@ module Liquid
       true
     end
   end
-
-  Template.register_tag('capture', Capture)
 end

lib/liquid/tags/case.rb

@@ -123,6 +123,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('case', Case)
 end

lib/liquid/tags/comment.rb

@@ -85,6 +85,4 @@ module Liquid
       raise_tag_never_closed("raw")
     end
   end
-
-  Template.register_tag('comment', Comment)
 end

lib/liquid/tags/continue.rb

@@ -17,6 +17,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('continue', Continue)
 end

lib/liquid/tags/cycle.rb

@@ -26,14 +26,20 @@ module Liquid
       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] ||= {}
 
@@ -72,6 +78,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('cycle', Cycle)
 end

lib/liquid/tags/decrement.rb

@@ -35,6 +35,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('decrement', Decrement)
 end

lib/liquid/tags/echo.rb

@@ -36,6 +36,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('echo', Echo)
 end

lib/liquid/tags/for.rb

@@ -92,7 +92,8 @@ module Liquid
       @variable_name = p.consume(:id)
       raise SyntaxError, options[:locale].t("errors.syntax.for_invalid_in") unless p.id?('in')
 
-      @collection_name = p.expression
+      collection_name  = p.expression
+      @collection_name = parse_expression(collection_name)
 
       @name     = "#{@variable_name}-#{collection_name}"
       @reversed = p.id?('reversed')
@@ -103,7 +104,7 @@ module Liquid
           raise SyntaxError, options[:locale].t("errors.syntax.for_invalid_attribute")
         end
         p.consume(:colon)
-        set_attribute(attribute, p.expression, do_parse: false)
+        set_attribute(attribute, p.expression)
       end
       p.consume(:end_of_string)
     end
@@ -173,18 +174,16 @@ module Liquid
       output
     end
 
-    def set_attribute(key, expr, do_parse: true)
+    def set_attribute(key, expr)
       case key
       when 'offset'
         @from = if expr == 'continue'
           :continue
-        elsif do_parse
-          parse_expression(expr)
         else
-          expr
+          parse_expression(expr)
         end
       when 'limit'
-        @limit = do_parse ? parse_expression(expr) : expr
+        @limit = parse_expression(expr)
       end
     end
 
@@ -202,6 +201,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('for', For)
 end

lib/liquid/tags/if.rb

@@ -120,9 +120,9 @@ module Liquid
     end
 
     def parse_comparison(p)
-      a = p.expression
+      a = parse_expression(p.expression)
       if (op = p.consume?(:comparison))
-        b = p.expression
+        b = parse_expression(p.expression)
         Condition.new(a, op, b)
       else
         Condition.new(a)
@@ -135,6 +135,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('if', If)
 end

lib/liquid/tags/ifchanged.rb

@@ -14,6 +14,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('ifchanged', Ifchanged)
 end

lib/liquid/tags/include.rb

@@ -110,6 +110,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('include', Include)
 end

lib/liquid/tags/increment.rb

@@ -35,6 +35,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('increment', Increment)
 end

lib/liquid/tags/inline_comment.rb

@@ -25,6 +25,4 @@ module Liquid
       true
     end
   end
-
-  Template.register_tag('#', InlineComment)
 end

lib/liquid/tags/raw.rb

@@ -56,6 +56,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('raw', Raw)
 end

lib/liquid/tags/render.rb

@@ -108,6 +108,4 @@ module Liquid
       end
     end
   end
-
-  Template.register_tag('render', Render)
 end

lib/liquid/tags/table_row.rb

@@ -65,6 +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
@@ -91,6 +97,4 @@ module Liquid
       raise Liquid::ArgumentError, "invalid integer"
     end
   end
-
-  Template.register_tag('tablerow', TableRow)
 end

lib/liquid/tags/unless.rb

@@ -44,6 +44,4 @@ module Liquid
       output
     end
   end
-
-  Template.register_tag('unless', Unless)
 end

lib/liquid/template.rb

@@ -18,42 +18,6 @@ module Liquid
     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
@@ -61,46 +25,71 @@ 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)
+        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.
@@ -162,11 +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
@@ -226,8 +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/template/tag_registry.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+module Liquid
+  class Template
+    class TagRegistry
+      include Enumerable
+
+      def initialize(tags = nil)
+        @tags  = {}
+        @cache = {}
+        tags.each { |tag_name, klass| self[tag_name] = klass }
+        Deprecations.warn("Template::TagRegistry", "Use a Environment instance with zeitwerk")
+      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 delete(tag_name)
+        Deprecations.warn("Template::TagRegistry#delete", "Use a Environment instance with immutable tags")
+        @tags.delete(tag_name)
+        @cache.delete(tag_name)
+      end
+
+      def []=(tag_name, klass)
+        @tags[tag_name]  = klass.name
+        @cache[tag_name] = klass
+      end
+
+      def each(&block)
+        @tags.each(&block)
+      end
+
+      private
+
+      def lookup_class(name)
+        Object.const_get(name)
+      end
+    end
+  end
+end

lib/liquid/variable.rb

@@ -65,11 +65,11 @@ module Liquid
 
       return if p.look(:end_of_string)
 
-      @name = p.expression
+      @name = parse_context.parse_expression(p.expression)
       while p.consume?(:pipe)
         filtername = p.consume(:id)
         filterargs = p.consume?(:colon) ? parse_filterargs(p) : []
-        @filters << parse_strict_filter_expressions(filtername, filterargs)
+        @filters << parse_filter_expressions(filtername, filterargs)
       end
       p.consume(:end_of_string)
     end
@@ -132,22 +132,6 @@ module Liquid
       result
     end
 
-    def parse_strict_filter_expressions(filter_name, args)
-      filter_args  = []
-      keyword_args = nil
-      args.each do |a|
-        if a.is_a?(Liquid::Parser::Kwarg)
-          keyword_args ||= {}
-          keyword_args[a.name] = a.value
-        else
-          filter_args << a.value
-        end
-      end
-      result = [filter_name, filter_args]
-      result << keyword_args if keyword_args
-      result
-    end
-
     def evaluate_filter_expressions(context, filter_args, filter_kwargs)
       parsed_args = filter_args.map { |expr| context.evaluate(expr) }
       if filter_kwargs

lib/liquid/variable_lookup.rb

@@ -6,24 +6,16 @@ module Liquid
 
     attr_reader :name, :lookups
 
-    def self.parse(markup, parse_context = nil)
-      new(markup, parse_context)
+    def self.parse(markup)
+      new(markup)
     end
 
-    def self.new_with(name, lookups, command_flags)
-      instance = allocate
-      instance.instance_variable_set(:@name, name)
-      instance.instance_variable_set(:@lookups, lookups)
-      instance.instance_variable_set(:@command_flags, command_flags)
-      instance
-    end
-
-    def initialize(markup, parse_context = nil)
+    def initialize(markup)
       lookups = markup.scan(VariableParser)
 
       name = lookups.shift
       if name&.start_with?('[') && name&.end_with?(']')
-        name = Expression.parse(name[1..-2], parse_context)
+        name = Expression.parse(name[1..-2])
       end
       @name = name
 
@@ -33,7 +25,7 @@ module Liquid
       @lookups.each_index do |i|
         lookup = lookups[i]
         if lookup&.start_with?('[') && lookup&.end_with?(']')
-          lookups[i] = Expression.parse(lookup[1..-2], parse_context)
+          lookups[i] = Expression.parse(lookup[1..-2])
         elsif COMMAND_METHODS.include?(lookup)
           @command_flags |= 1 << i
         end

lib/liquid/version.rb

@@ -2,5 +2,5 @@
 # frozen_string_literal: true
 
 module Liquid
-  VERSION = "5.5.0"
+  VERSION = "5.6.0.alpha"
 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

@@ -3,6 +3,7 @@
 require 'benchmark/ips'
 require_relative 'theme_runner'
 
+RubyVM::YJIT.enable if defined?(RubyVM::YJIT)
 Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
 profiler = ThemeRunner.new
 

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

product.liquid

@@ -1,34 +0,0 @@
-<div id="product-left">
-  {% for image in product.images %}<div id="product-image">
-    <a href="{{ image | product_img_url: 'large' }}" rel="lightbox[images]" title="{{ product.title | escape }}"><img src="{{ image | product_img_url: 'medium' }}" alt="{{ product.title | escape }}" /></a>
-  </div>
-  {% endfor %}
-</div>
-<div id="product-right">
-  <h1>{{ product.title }}</h1>
-  {{ product.description }}
-
-  {% if product.available %}
-  <form action="/cart/add" method="post">
-
-    <div id="product-variants">
-      <div id="price-field"></div>
-
-      <select id="product-select" name='id'>
-        {% for variant in product.variants %}
-          <option value="{{ variant.id }}">{{ variant.title }} - {{ variant.price | money }}</option>
-        {% endfor %}
-      </select>
-    </div>
-
-    <input type="image" src="purchase.png" name="add" value="Purchase" id="purchase" />
-  </form>
-  {% else %}
-    <p class="bold-red">This product is temporarily unavailable</p>
-  {% endif %}
-
-  <div id="product-details">
-    <strong>Continue Shopping</strong><br />
-    Browse more {{ product.type }} or additional {{ product.vendor }} products.
-  </div>
-</div>

test/integration/error_handling_test.rb

@@ -219,6 +219,21 @@ class ErrorHandlingTest < Minitest::Test
     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
     template   = Liquid::Template.parse('This is a runtime error: {{ errors.runtime_error }}', line_numbers: true)
     exceptions = []
@@ -242,16 +257,10 @@ 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

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
 

test/integration/tags/include_tag_test.rb

@@ -49,14 +49,6 @@ 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',
@@ -214,9 +206,10 @@ class IncludeTagTest < Minitest::Test
 
   def test_include_tag_caches_second_read_of_same_partial
     file_system = CountingFileSystem.new
+    environment = Liquid::Environment.build(file_system: file_system)
     assert_equal(
       'from CountingFileSystemfrom CountingFileSystem',
-      Template.parse("{% include 'pick_a_source' %}{% include 'pick_a_source' %}").render!({}, registers: { file_system: file_system }),
+      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

test/integration/tags/table_row_test.rb

@@ -207,4 +207,52 @@ class TableRowTest < Minitest::Test
       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/test_helper.rb

@@ -42,10 +42,11 @@ module Minitest
       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 || {})
+      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)
+      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
@@ -78,22 +79,12 @@ 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)
@@ -104,18 +95,11 @@ module Minitest
       Liquid::Template.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

test/unit/lexer_unit_test.rb

@@ -50,4 +50,14 @@ class LexerUnitTest < Minitest::Test
       Lexer.new("%").tokenize
     end
   end
+
+  def test_negative_numbers
+    tokens = Lexer.new("foo | default: -1").tokenize
+    assert_equal([[:id, 'foo'], [:pipe, '|'], [:id, 'default'], [:colon, ":"], [:number, '-1'], [:end_of_string]], tokens)
+  end
+
+  def test_greater_than_two_digits
+    tokens = Lexer.new("foo > 12").tokenize
+    assert_equal([[:id, 'foo'], [:comparison, '>'], [:number, '12'], [:end_of_string]], tokens)
+  end
 end

test/unit/strainer_template_unit_test.rb

@@ -58,8 +58,9 @@ 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/template_unit_test.rb

@@ -36,7 +36,6 @@ class TemplateUnitTest < Minitest::Test
     assert(Template.tags['custom'].equal?(original_klass))
   ensure
     Object.send(:remove_const, :CustomTag)
-    Template.tags.delete('custom')
     Liquid.cache_classes = original_cache_setting
   end
 
@@ -46,36 +45,26 @@ class TemplateUnitTest < Minitest::Test
 
     original_klass = Class.new
     Object.send(:const_set, :CustomTag, original_klass)
-    Template.register_tag('custom', CustomTag)
+    with_custom_tag('custom', CustomTag) do
+      Object.send(:remove_const, :CustomTag)
 
-    Object.send(:remove_const, :CustomTag)
+      new_klass = Class.new
+      Object.send(:const_set, :CustomTag, new_klass)
 
-    new_klass = Class.new
-    Object.send(:const_set, :CustomTag, new_klass)
-
-    assert(Template.tags['custom'].equal?(new_klass))
+      assert(Template.tags['custom'].equal?(new_klass))
+    end
   ensure
     Object.send(:remove_const, :CustomTag)
-    Template.tags.delete('custom')
     Liquid.cache_classes = original_cache_setting
   end
 
   class FakeTag; end
 
-  def test_tags_delete
-    Template.register_tag('fake', FakeTag)
-    assert_equal(FakeTag, Template.tags['fake'])
-
-    Template.tags.delete('fake')
-    assert_nil(Template.tags['fake'])
-  end
-
   def test_tags_can_be_looped_over
-    Template.register_tag('fake', FakeTag)
-    result = Template.tags.map { |name, klass| [name, klass] }
-    assert(result.include?(["fake", "TemplateUnitTest::FakeTag"]))
-  ensure
-    Template.tags.delete('fake')
+    with_custom_tag('fake', FakeTag) do
+      result = Template.tags.map { |name, klass| [name, klass] }
+      assert(result.include?(["fake", "TemplateUnitTest::FakeTag"]))
+    end
   end
 
   class TemplateSubclass < Liquid::Template