tests passing

.github/workflows/liquid.yml

@@ -11,10 +11,10 @@ jobs:
     strategy:
       matrix:
         entry:
-          - { ruby: 3.0, allowed-failure: false } # minimum supported
+          - { ruby: 2.7, allowed-failure: false } # minimum supported
           - { ruby: 3.2, allowed-failure: false }
           - { ruby: 3.3, allowed-failure: false } # latest
-          - { ruby: ruby-head, allowed-failure: false }
+          - { ruby: ruby-head, allowed-failure: true }
     name: Test Ruby ${{ matrix.entry.ruby }}
     steps:
       - uses: actions/checkout@v3

.gitignore

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

.ruby-version

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

Gemfile

@@ -23,4 +23,12 @@ group :test do
   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: 'main'
+  end
+end
+
+group :development do
+  gem "webrick"
 end

Gemfile.lock

@@ -0,0 +1,77 @@
+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 (5.6.0.alpha)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.2)
+    base64 (0.2.0)
+    benchmark-ips (2.13.0)
+    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
+    racc (1.7.3)
+    rainbow (3.1.1)
+    rake (13.2.1)
+    regexp_parser (2.9.0)
+    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)
+    terminal-table (3.0.2)
+      unicode-display_width (>= 1.1.1, < 3)
+    unicode-display_width (2.5.0)
+    webrick (1.8.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  base64
+  benchmark-ips
+  liquid!
+  liquid-c!
+  memory_profiler
+  minitest
+  rake (~> 13.0)
+  rubocop (~> 1.61.0)
+  rubocop-performance
+  rubocop-shopify (~> 2.12.0)
+  stackprof
+  terminal-table
+  webrick
+
+BUNDLED WITH
+   2.5.7

Rakefile

@@ -43,6 +43,8 @@ task :test do
   Rake::Task['base_test'].invoke
 
   if RUBY_ENGINE == 'ruby' || RUBY_ENGINE == 'truffleruby'
+    ENV['LIQUID_C'] = '1'
+
     ENV['LIQUID_PARSER_MODE'] = 'lax'
     Rake::Task['integration_test'].reenable
     Rake::Task['integration_test'].invoke
@@ -79,25 +81,6 @@ namespace :benchmark do
   task :strict do
     ruby "./performance/benchmark.rb strict"
   end
-
-  desc "Run unit benchmarks"
-  namespace :unit do
-    desc "Run all unit benchmarks"
-    task :all do
-      Dir["./performance/unit/*_benchmark.rb"].each do |file|
-        puts "🧪 Running #{file}"
-        ruby file
-      end
-    end
-
-    %w[lexer loom].each do |benchmark|
-      desc "Run the #{benchmark} benchmark"
-      task benchmark.to_sym do
-        puts "🧪 Running #{benchmark}"
-        ruby "./performance/unit/#{benchmark}_benchmark.rb"
-      end
-    end
-  end
 end
 
 namespace :profile do

example/server/parser_attempt.rb

@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+require 'bundler/inline'
+
+gemfile(true) do
+  source "https://rubygems.org"
+  gem 'liquid'
+end
+
+require 'liquid'
+
+class Parser
+  def initialize(template)
+    @template = template
+  end
+
+  def parse
+    @parsed_template = Liquid::Template.parse(@template)
+  end
+
+  def test_parse
+    document = @parsed_template.root
+
+    variables = []
+
+    if document.is_a?(Liquid::Document)
+      body = document.body
+
+      if body.is_a?(Liquid::BlockBody)
+        body.nodelist.each do |node|
+          next unless node.is_a?(Liquid::Variable)
+
+          puts node.inspect
+          variable_name = node.name.name
+          variables << variable_name
+        end
+      end
+    end
+    puts "Variables: #{variables}"
+  end
+
+  def render
+    @parsed_template.render
+  end
+end
+
+starter_template = "{{ foo }}"
+starter_template_2 = "{{foo}}, {{bar}}"
+starter_template_2_1 = "{{ foo }} and {{ bar }}"
+starter_template_3 = "{% assign foo = 'bar' %}{{ foo }}"
+# Let's start small here
+template = <<~LIQUID
+  {% assign foo = 'bar' %}
+  {{ foo }}
+LIQUID
+
+parser = Parser.new(starter_template)
+parser.parse
+parser.test_parse

example/server/templates/index.liquid

@@ -1,6 +1,71 @@
-<p>Hello world!</p>
+<!DOCTYPE html>
+  <html lang="en">
 
-<p>It is {{date}}</p>
+  <head>
+      <meta charset="UTF-8">
+      <meta name="viewport" content="width=device-width, initial-scale=1.0">
+      <title>Simple Code Editor</title>
+      <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.65.5/codemirror.min.css">
+      <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.65.5/theme/dracula.min.css">
+      <script src="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.65.5/codemirror.min.js"></script>
+      <script src="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.65.5/mode/xml/xml.min.js"></script>
+      <script src="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.65.5/mode/htmlmixed/htmlmixed.min.js"></script>
+      <style>
+        .liquid, .CodeMirror {
+          position: fixed;
+          height: 100vh;
+          width: 50vw;
+          top: 0;
+          font-size: 24px;
+        }
+        .liquid {
+          left: 0;
+        }
+        .CodeMirror {
+          left: 50%;
+        }
+        .CodeMirror-hscrollbar {
+          overflow: hidden;
+        }
+      </style>
+  </head>
 
+  <body>
+    <div class="liquid">
+      {% snippet "main" %}
 
-<p>Check out the <a href="/products">Products</a> screen </p>
+        {% # Snippet input %}
+        {% snippet "input" |type, name| %}
+          <div>
+            <label>{{ type | capitalize }}</label>
+            <input type={{ type }}>
+          </div>
+        {% endsnippet %}
+
+        {% snippet "league" %}
+        <h1>Welcome to the league of super evil</h1>
+        {% endsnippet %}
+
+        {% render "league" %}
+        {% render "input", type: "text" %}
+        {% render "input", type: "password" %}
+
+      {% endsnippet %}
+      {% render 'main' %}
+    </div>
+
+    <textarea id="code">
+      {% capture html %}{% render 'main' %}{% endcapture %}
+      {{ html | escape }}
+    </textarea>
+
+    <script>
+      const editorElement = document.querySelector('#code')
+      const editor = CodeMirror.fromTextArea(editorElement, {
+          lineNumbers: true,
+          mode: "htmlmixed",
+          theme: "dracula"
+      });
+    </script>
+  </body>
+</html>

lib/liquid.rb

@@ -44,11 +44,15 @@ module Liquid
   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/template/tag_registry"
 require 'liquid/standardfilters'
 require 'liquid/file_system'
 require 'liquid/parser_switching'
@@ -68,6 +72,7 @@ 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/tag'
@@ -86,4 +91,3 @@ require 'liquid/partial_cache'
 require 'liquid/usage'
 require 'liquid/registers'
 require 'liquid/template_factory'
-require 'liquid/loom'

lib/liquid/block_body.rb

@@ -31,11 +31,10 @@ module Liquid
       end
     end
 
-    # TODO: Freeze the nodelist after optimization
-    # def freeze
-    #   @nodelist.freeze
-    #   super
-    # end
+    def freeze
+      @nodelist.freeze
+      super
+    end
 
     private def parse_for_liquid_tag(tokenizer, parse_context)
       while (token = tokenizer.shift)
@@ -155,12 +154,6 @@ module Liquid
           end
           new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
           @blank &&= new_tag.blank?
-
-          if parse_context.eager_optimize
-            next if new_tag.nodelist&.all? { !_1.is_a?(String) && _1.nodelist.empty? } # this is an empty block
-            next if new_tag.is_a?(If) && new_tag.blocks.empty? # this is an empty If block
-          end
-
           @nodelist << new_tag
         when token.start_with?(VARSTART)
           whitespace_handler(token, parse_context)
@@ -253,17 +246,10 @@ module Liquid
     end
 
     def create_variable(token, parse_context)
-      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)
-
+      if token =~ ContentOfVariable
+        markup = Regexp.last_match(1)
         return Variable.new(markup, parse_context)
       end
-
       BlockBody.raise_missing_variable_terminator(token, parse_context)
     end
 

lib/liquid/context.rb

@@ -19,7 +19,7 @@ module Liquid
 
     # rubocop:disable Metrics/ParameterLists
     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)
+      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 = {}, environment = Environment.default)
@@ -143,7 +143,6 @@ module Liquid
       check_overflow
 
       self.class.build(
-        environment: @environment,
         resource_limits: resource_limits,
         static_environments: static_environments,
         registers: Registers.new(registers),

lib/liquid/environment.rb

@@ -41,7 +41,7 @@ module Liquid
       # @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.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
@@ -74,7 +74,7 @@ module Liquid
     # Initializes a new environment instance.
     # @api private
     def initialize
-      @tags = Tags::STANDARD_TAGS.dup
+      @tags = Template::TagRegistry.new(Tags::STANDARD_TAGS)
       @error_mode = :lax
       @strainer_template = Class.new(StrainerTemplate).tap do |klass|
         klass.add_filter(StandardFilters)

lib/liquid/lexer.rb

@@ -1,9 +1,8 @@
 # frozen_string_literal: true
 
 require "strscan"
-
 module Liquid
-  class Lexer1
+  class Lexer
     SPECIALS = {
       '|' => :pipe,
       '.' => :dot,
@@ -59,179 +58,4 @@ 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

@@ -4,6 +4,7 @@
       tag_unexpected_args: "Syntax Error in '%{tag}' - Valid syntax: %{tag}"
       assign: "Syntax Error in 'assign' - Valid syntax: assign [var] = [source]"
       capture: "Syntax Error in 'capture' - Valid syntax: capture [var]"
+      snippet: "Syntax Error in 'snippet' - Valid syntax: snippet [quoted string]"
       case: "Syntax Error in 'case' - Valid syntax: case [condition]"
       case_invalid_when: "Syntax Error in tag 'case' - Valid when condition: {% when [condition] [or condition2...] %}"
       case_invalid_else: "Syntax Error in tag 'case' - Valid else condition: {% else %} (no parameters) "

lib/liquid/loom.rb

@@ -1,123 +0,0 @@
-# frozen_string_literal: true
-
-module Liquid
-  class Loom
-    MERGABLE_IF_OPERATORS = ["==", ">", "<", "!="].freeze
-    EQUAL_OP = "==".freeze
-
-    class << self
-      def optimize(template)
-        new(template).optimize
-      end
-    end
-
-    def initialize template
-      @root = template.root
-    end
-
-    def optimize
-      merge_if_blocks
-    end
-
-    def merge_if_blocks
-      nodelist_list = [@root.nodelist]
-
-      while nodelist_list.any?
-        next_nodelist_list = []
-
-        nodelist_list.each do |nodelist|
-          i = 0
-          while i < nodelist.length
-            node = nodelist[i]
-            chain_if_blocks(nodelist, node, i) if node.is_a?(If)
-            i += 1
-          end
-        end
-
-        nodelist_list = next_nodelist_list
-      end
-    end
-
-    private
-
-    def mergable_if_blocks?(target_if, next_if)
-      target_left = target_if.blocks.first.left
-      target_right = target_if.blocks.first.right
-      next_left = next_if.blocks.first.left
-      next_right = next_if.blocks.first.right
-
-      used_variables = Hash.new { |h, k| h[k] = 0 }
-
-      [
-        target_if.blocks.first.left,
-        target_if.blocks.first.right,
-        next_if.blocks.first.left,
-        next_if.blocks.first.right
-      ].each do |var|
-        if var.is_a?(VariableLookup)
-          used_variables[var.name] += 1
-        end
-      end
-
-      return if used_variables.keys.count > 1
-
-      most_used_variable_name = used_variables.keys[0]
-
-      # TODO: I probably can't do this
-      # It might be possible to get different result between a > b and b < a
-      # Move most commonly used variable to the left side
-      if (target_left.is_a?(VariableLookup) && target_left.name != most_used_variable_name) || (target_right.is_a?(VariableLookup) && target_right.name == most_used_variable_name)
-        target_left, target_right = target_right, target_left
-      end
-
-      if (next_left.is_a?(VariableLookup) && next_left.name != most_used_variable_name) || (next_right.is_a?(VariableLookup) && next_right.name == most_used_variable_name)
-        next_left, next_right = next_right, next_left
-      end
-
-      return false unless target_left.is_a?(VariableLookup) && next_left.is_a?(VariableLookup)
-      return false if target_left.name != next_left.name
-
-      return false if target_right.nil? || next_right.nil?
-
-
-      # we need to be conversative here and only can merge ==, >, <, and != operators
-      target_operator = target_if.blocks.first.operator
-      next_operator = next_if.blocks.first.operator
-
-      return false unless MERGABLE_IF_OPERATORS.include?(target_operator) && MERGABLE_IF_OPERATORS.include?(next_operator)
-
-      return false if target_operator == next_operator && target_right == next_right
-
-      return false if target_right.is_a?(VariableLookup) || next_right.is_a?(VariableLookup)
-
-      true
-    end
-
-    def chain_if_blocks(nodelist, first_if_node, first_if_index)
-      used_variables = Set.new
-
-      # only check the top level Condition (ignore children conditions for now)
-      first_if_node.blocks.each do |condition|
-        used_variables << condition.left
-        used_variables << condition.right if condition.right
-      end
-
-      if_blocks = []
-
-      nodelist[first_if_index + 1..-1].each do |node|
-        break unless node.is_a?(If)
-
-        # check if the variables used in the current block are used in the previous block
-        break unless mergable_if_blocks?(first_if_node, node)
-
-        if_blocks << node
-      end
-
-      nodelist.delete_if { |node| if_blocks.include?(node) }
-
-      if_blocks.each do |if_block|
-        first_if_node.blocks << if_block.blocks.first
-      end
-    end
-  end
-end

lib/liquid/parse_context.rb

@@ -3,7 +3,7 @@
 module Liquid
   class ParseContext
     attr_accessor :locale, :line_number, :trim_whitespace, :depth
-    attr_reader :partial, :warnings, :error_mode, :environment, :eager_optimize
+    attr_reader :partial, :warnings, :error_mode, :environment
 
     def initialize(options = Const::EMPTY_HASH)
       @environment = options.fetch(:environment, Environment.default)
@@ -11,7 +11,6 @@ module Liquid
 
       @locale   = @template_options[:locale] ||= I18n.new
       @warnings = []
-      @eager_optimize = options.fetch(:eager_optimize, ENV["OPTIMIZE"] == "true")
 
       self.depth   = 0
       self.partial = false

lib/liquid/parse_tree_visitor.rb

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

lib/liquid/parser.rb

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

lib/liquid/standardfilters.rb

@@ -877,7 +877,7 @@ module Liquid
     #   - [`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)

lib/liquid/strainer_factory.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Liquid
+  # StrainerFactory is the factory for the filters system.
+  module StrainerFactory
+    extend self
+
+    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 = Const::EMPTY_ARRAY, environment = Environment.default)
+      Deprecations.warn("StrainerFactory.create", "StrainerFactory.create_strainer")
+      environment.create_strainer(context, filters)
+    end
+
+    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/tags.rb

@@ -19,6 +19,7 @@ require_relative "tags/comment"
 require_relative "tags/raw"
 require_relative "tags/render"
 require_relative "tags/cycle"
+require_relative "tags/snippet"
 
 module Liquid
   module Tags
@@ -42,6 +43,7 @@ module Liquid
       'if' => If,
       'echo' => Echo,
       'tablerow' => TableRow,
+      'snippet' => Snippet,
     }.freeze
   end
 end

lib/liquid/tags/if.rb

@@ -23,7 +23,6 @@ module Liquid
     def initialize(tag_name, markup, options)
       super
       @blocks = []
-      @has_else_block = false
       push_block('if', markup)
     end
 
@@ -34,44 +33,17 @@ module Liquid
     def parse(tokens)
       while parse_body(@blocks.last.attachment, tokens)
       end
-
-      if parse_context.eager_optimize && definitive_false_statement?
-        @blocks.clear
-      else
-        @blocks.reverse_each do |block|
-          block.attachment.remove_blank_strings if blank?
-          block.attachment.freeze
-        end
+      @blocks.reverse_each do |block|
+        block.attachment.remove_blank_strings if blank?
+        block.attachment.freeze
       end
     end
 
-    def definitive_false_statement?
-      # check if any blocks have variable lookups
-      @blocks.each do |condition|
-        return false if condition.left.is_a?(VariableLookup) || condition.right&.is_a?(VariableLookup)
-
-        child_condition = condition.child_condition
-
-        while child_condition
-          return false if child_condition&.left.is_a?(VariableLookup) || child_condition&.right&.is_a?(VariableLookup)
-          child_condition = child_condition.child_condition
-        end
-      end
-
-      # check if all blocks are false
-      @blocks.each do |condition|
-        return false if condition.evaluate
-      end
-
-      true
-    end
-
     ELSE_TAG_NAMES = ['elsif', 'else'].freeze
     private_constant :ELSE_TAG_NAMES
 
     def unknown_tag(tag, markup, tokens)
       if ELSE_TAG_NAMES.include?(tag)
-        @has_else_block = true
         push_block(tag, markup)
       else
         super

lib/liquid/tags/render.rb

@@ -66,6 +66,24 @@ module Liquid
       template_name = @template_name_expr
       raise ::ArgumentError unless template_name.is_a?(String)
 
+      # Inline snippets take precedence over external snippets
+      if (inline_snippet = context.registers[:inline_snippet][template_name])
+        inner_context = context.new_isolated_subcontext
+
+        snippet_body = inline_snippet[:body]
+        snippet_args = inline_snippet[:args]
+        # Validate and set the arguments in the inner context
+        @attributes.each do |key, value|
+          unless snippet_args.include?(key)
+            raise Liquid::ArgumentError, "Invalid argument `#{key}` for snippet `#{template_name}`"
+          end
+
+          inner_context[key] = context.evaluate(value)
+        end
+
+        return output << snippet_body.render(inner_context)
+      end
+
       partial = PartialCache.load(
         template_name,
         context: context,

lib/liquid/tags/snippet.rb

@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+module Liquid
+  # @liquid_public_docs
+  # @liquid_type tag
+  # @liquid_category theme
+  # @liquid_name snippet
+  # @liquid_summary
+  #   Creates a new inline snippet using a string value as the identifier.
+  # @liquid_description
+  #   You can create inline snippets to make your Liquid code more modular.
+  # @liquid_syntax
+  #   {% snippet "input" %}
+  #     value
+  #   {% endsnippet %}
+  class Snippet < Block
+    SYNTAX = /(#{QuotedString})(?:\s*\|\s*([\w\s,]+)\s*\|)?/o
+    def initialize(tag_name, markup, options)
+      super
+
+      if markup =~ SYNTAX
+        @to = Regexp.last_match(1)
+        args = Regexp.last_match(2)
+
+        @args = args ? args.split(/\s*,\s*/) : []
+      else
+        raise SyntaxError, options[:locale].t("errors.syntax.snippet")
+      end
+    end
+
+    def render(context)
+      context.registers[:inline_snippet] ||= {}
+      context.registers[:inline_snippet][snippet_id] = {
+        body: snippet_body,
+        args: @args,
+      }
+      ''
+    end
+
+    private
+
+    def snippet_id
+      @to[1, @to.size - 2]
+    end
+
+    def snippet_body
+      body = @body
+      body
+    end
+  end
+end

lib/liquid/template.rb

@@ -82,11 +82,7 @@ module Liquid
       # See Liquid::Profiler for more information
       def parse(source, options = {})
         environment = options[:environment] || Environment.default
-        template = new(environment: environment).parse(source, options)
-
-        Loom.optimize(template) if options[:eager_optimize]
-
-        template
+        new(environment: environment).parse(source, options)
       end
     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

@@ -68,7 +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) : Const::EMPTY_ARRAY
+        filterargs = p.consume?(:colon) ? parse_filterargs(p) : []
         @filters << parse_filter_expressions(filtername, filterargs)
       end
       p.consume(:end_of_string)
@@ -95,21 +95,15 @@ module Liquid
 
     def render_to_output_buffer(context, output)
       obj = render(context)
-      render_obj_to_output(obj, output)
-      output
-    end
 
-    def render_obj_to_output(obj, output)
-      case obj
-      when NilClass
-        # Do nothing
-      when Array
-        obj.each do |o|
-          render_obj_to_output(o, output)
-        end
-      when
+      if obj.is_a?(Array)
+        output << obj.join
+      elsif obj.nil?
+      else
         output << obj.to_s
       end
+
+      output
     end
 
     def disabled?(_context)

lib/liquid/version.rb

@@ -2,5 +2,5 @@
 # frozen_string_literal: true
 
 module Liquid
-  VERSION = "5.6.0.rc2"
+  VERSION = "5.6.0.alpha"
 end

liquid.gemspec

@@ -13,11 +13,11 @@ Gem::Specification.new do |s|
   s.summary     = "A secure, non-evaling end user template engine with aesthetic markup."
   s.authors     = ["Tobias Lütke"]
   s.email       = ["[email protected]"]
-  s.homepage    = "https://shopify.github.io/liquid/"
+  s.homepage    = "http://www.liquidmarkup.org"
   s.license     = "MIT"
   # s.description = "A secure, non-evaling end user template engine with aesthetic markup."
 
-  s.required_ruby_version     = ">= 3.0.0"
+  s.required_ruby_version     = ">= 2.7.0"
   s.required_rubygems_version = ">= 1.3.7"
 
   s.metadata['allowed_push_host'] = 'https://rubygems.org'
@@ -28,9 +28,6 @@ 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

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

performance/shopify/liquid.rb

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

performance/unit/lexer_benchmark.rb

@@ -1,62 +0,0 @@
-# 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

performance/unit/loom_benchmark.rb

@@ -1,56 +0,0 @@
-# frozen_string_literal: true
-
-require "benchmark/ips"
-require 'liquid'
-
-RubyVM::YJIT.enable
-
-TEMPLATE = <<~LIQUID
-{% if false %}
-  {% for i in (1..1000000) %}
-    {{ "Hello world!" }}
-  {% endfor %}
-{% endif %}
-
-{% assign result = 1 %}
-{% if foo == 1 %}{% assign result = 1 %}{% endif %}{% if foo == 2 %}{% assign result = 2 %}{% endif %}{% if foo == 3 %}{% assign result = 3 %}{% endif %}
-Result: {{ result }}
-LIQUID
-
-baseline_template = Liquid::Template.parse(TEMPLATE, eager_optimize: false)
-optimized_template = Liquid::Template.parse(TEMPLATE, eager_optimize: true)
-
-[nil, 1, 2, 3].each do |foo|
-  baseline_output = baseline_template.render('foo' => foo)
-  optimized_output = optimized_template.render('foo' => foo)
-
-  if baseline_output != optimized_output
-    puts "WARNING! Baseline and optimized templates render differently for foo=#{foo}"
-    puts "Baseline: #{baseline_output}"
-    puts "Optimized: #{optimized_output}"
-
-    raise
-  end
-end
-
-def render(template, foo)
-  template.render('foo' => foo)
-end
-
-Benchmark.ips do |x|
-  x.config(time: 20, warmup: 3)
-
-  x.report("baseline") do
-    [nil, 1, 2, 3].each do |foo|
-      render(baseline_template, foo)
-    end
-  end
-
-  x.report("optimized") do
-    [nil, 1, 2, 3].each do |foo|
-      render(optimized_template, foo)
-    end
-  end
-
-  x.compare!
-end

test/integration/context_test.rb

@@ -672,21 +672,6 @@ class ContextTest < Minitest::Test
     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

@@ -203,19 +203,20 @@ class ErrorHandlingTest < Minitest::Test
   end
 
   def test_setting_default_exception_renderer
+    old_exception_renderer = Liquid::Template.default_exception_renderer
     exceptions = []
-    default_exception_renderer = ->(e) {
+    Liquid::Template.default_exception_renderer = ->(e) {
       exceptions << e
       ''
     }
-
-    env = Liquid::Environment.build(exception_renderer: default_exception_renderer)
-    template = Liquid::Template.parse('This is a runtime error: {{ errors.argument_error }}', environment: env)
+    template = Liquid::Template.parse('This is a runtime error: {{ errors.argument_error }}')
 
     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

test/integration/parsing_quirks_test.rb

@@ -131,16 +131,4 @@ 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::Environment.default.file_system = ProfilingFileSystem.new
+    Liquid::Template.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.inspect}=>#{@context.registers[@value].inspect}}"
+    { @value => @context.registers[@value] }
   end
 end
 

test/integration/tags/include_tag_test.rb

@@ -174,10 +174,10 @@ class IncludeTagTest < Minitest::Test
       end
     end
 
-    env = Liquid::Environment.build(file_system: infinite_file_system.new)
+    Liquid::Template.file_system = infinite_file_system.new
 
     assert_raises(Liquid::StackLevelError) do
-      Template.parse("{% include 'loop' %}", environment: env).render!
+      Template.parse("{% include 'loop' %}").render!
     end
   end
 
@@ -264,27 +264,26 @@ class IncludeTagTest < Minitest::Test
   end
 
   def test_does_not_add_error_in_strict_mode_for_missing_variable
-    env = Liquid::Environment.build(file_system: TestFileSystem.new)
+    Liquid::Template.file_system = TestFileSystem.new
 
-    a = Liquid::Template.parse(' {% include "nested_template" %}', environment: env)
+    a = Liquid::Template.parse(' {% include "nested_template" %}')
     a.render!
     assert_empty(a.errors)
   end
 
   def test_passing_options_to_included_templates
-    env = Liquid::Environment.build(file_system: TestFileSystem.new)
-
+    Liquid::Template.file_system = TestFileSystem.new
     assert_raises(Liquid::SyntaxError) do
-      Template.parse("{% include template %}", error_mode: :strict, environment: env).render!("template" => '{{ "X" || downcase }}')
+      Template.parse("{% include template %}", error_mode: :strict).render!("template" => '{{ "X" || downcase }}')
     end
     with_error_mode(:lax) do
-      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: true, environment: env).render!("template" => '{{ "X" || downcase }}'))
+      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: true).render!("template" => '{{ "X" || downcase }}'))
     end
     assert_raises(Liquid::SyntaxError) do
-      Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:locale], environment: env).render!("template" => '{{ "X" || downcase }}')
+      Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:locale]).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], environment: env).render!("template" => '{{ "X" || downcase }}'))
+      assert_equal('x', Template.parse("{% include template %}", error_mode: :strict, include_options_blacklist: [:error_mode]).render!("template" => '{{ "X" || downcase }}'))
     end
   end
 
@@ -335,11 +334,8 @@ class IncludeTagTest < Minitest::Test
   end
 
   def test_including_with_strict_variables
-    env = Liquid::Environment.build(
-      file_system: StubFileSystem.new('simple' => 'simple'),
-    )
-
-    template = Liquid::Template.parse("{% include 'simple' %}", error_mode: :warn, environment: env)
+    Liquid::Template.file_system = StubFileSystem.new({ "simple" => "simple" })
+    template = Liquid::Template.parse("{% include 'simple' %}", error_mode: :warn)
     template.render(nil, strict_variables: true)
 
     assert_equal([], template.errors)

test/integration/tags/render_tag_test.rb

@@ -82,22 +82,19 @@ class RenderTagTest < Minitest::Test
   end
 
   def test_recursively_rendered_template_does_not_produce_endless_loop
-    env = Liquid::Environment.build(
-      file_system: StubFileSystem.new('loop' => '{% render "loop" %}'),
-    )
+    Liquid::Template.file_system = StubFileSystem.new('loop' => '{% render "loop" %}')
 
     assert_raises(Liquid::StackLevelError) do
-      Template.parse('{% render "loop" %}', environment: env).render!
+      Template.parse('{% render "loop" %}').render!
     end
   end
 
   def test_sub_contexts_count_towards_the_same_recursion_limit
-    env = Liquid::Environment.build(
-      file_system: StubFileSystem.new('loop_render' => '{% render "loop_render" %}'),
+    Liquid::Template.file_system = StubFileSystem.new(
+      'loop_render' => '{% render "loop_render" %}',
     )
-
     assert_raises(Liquid::StackLevelError) do
-      Template.parse('{% render "loop_render" %}', environment: env).render!
+      Template.parse('{% render "loop_render" %}').render!
     end
   end
 

test/integration/tags/snippet_test.rb

@@ -0,0 +1,190 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class SnippetTest < Minitest::Test
+  include Liquid
+
+  def test_valid_inline_snippet
+    template = <<~LIQUID.strip
+      {% snippet "input" %}
+        Hey
+      {% endsnippet %}
+    LIQUID
+    expected = ''
+
+    assert_template_result(expected, template)
+  end
+
+  def test_invalid_inline_snippet
+    template = <<~LIQUID.strip
+      {% snippet input %}
+        Hey
+      {% endsnippet %}
+    LIQUID
+    expected = "Syntax Error in 'snippet' - Valid syntax: snippet [quoted string]"
+
+    assert_match_syntax_error(expected, template)
+  end
+
+  def test_render_inline_snippet
+    template = <<~LIQUID.strip
+      {% snippet "hey" %}
+      Hey
+      {% endsnippet %}
+
+      {%- render "hey" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+      Hey
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_multiple_inline_snippets
+    template = <<~LIQUID.strip
+      {% snippet "input" %}
+      <input />
+      {% endsnippet %}
+
+      {% snippet "banner" %}
+      <marquee direction="up" height="100px">
+        Welcome to my store!
+      </marquee>
+      {% endsnippet %}
+
+      {%- render "input" -%}
+      {%- render "banner" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+
+
+      <input />
+
+      <marquee direction="up" height="100px">
+        Welcome to my store!
+      </marquee>
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_inline_snippet_with_argument
+    template = <<~LIQUID.strip
+      {% snippet "input" |type| %}
+      <input type="{{ type }}" />
+      {% endsnippet %}
+
+      {%- render "input", type: "text" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+      <input type="text" />
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_inline_snippet_with_multiple_arguments
+    template = <<~LIQUID.strip
+      {% snippet "input" |type, value| %}
+      <input type="{{ type }}" value="{{ value }}" />
+      {% endsnippet %}
+
+      {%- render "input", type: "text", value: "Hello" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+      <input type="text" value="Hello" />
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_inline_snippets_using_same_argument_name
+    template = <<~LIQUID.strip
+      {% snippet "input" |type| %}
+      <input type="{{ type }}" />
+      {% endsnippet %}
+
+      {% snippet "inputs" |type, value| %}
+        <input type="{{ type }}" value="{{ value }}" />
+      {% endsnippet %}
+
+      {%- render "input", type: "text" -%}
+      {%- render "inputs", type: "password", value: "pass" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+
+
+      <input type="text" />
+
+        <input type="password" value="pass" />
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_inline_snippet_empty_string_when_missing_argument
+    template = <<~LIQUID.strip
+      {% snippet "input" |type| %}
+      <input type="{{ type }}" value="{{ value }}" />
+      {% endsnippet %}
+
+      {%- render "input", type: "text" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+      <input type="text" value="" />
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_inline_snippet_shouldnt_leak_context
+    template = <<~LIQUID.strip
+      {% snippet "input" |type, value| %}
+      <input type="{{ type }}" value="{{ value }}" />
+      {% endsnippet %}
+
+      {%- render "input", type: "text", value: "Hello" -%}
+
+      {{ type }}
+      {{ value }}
+    LIQUID
+    expected = <<~OUTPUT
+
+      <input type="text" value="Hello" />
+
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+
+  def test_render_multiple_inline_snippets_without_leaking_context
+    template = <<~LIQUID.strip
+      {% snippet "input" |type| %}
+      <input type="{{ type }}" />
+      {% endsnippet %}
+      {% snippet "no_leak" %}
+      <input type="{{ type }}" />
+      {% endsnippet %}
+
+      {%- render "input", type: "text" -%}
+      {%- render "no_leak" -%}
+    LIQUID
+    expected = <<~OUTPUT
+
+
+      <input type="text" />
+
+      <input type="" />
+    OUTPUT
+
+    assert_template_result(expected, template)
+  end
+end

test/integration/variable_test.rb

@@ -130,10 +130,6 @@ class VariableTest < Minitest::Test
     assert_template_result('bar', '{{ foo }}', { 'foo' => :bar })
   end
 
-  def test_nested_array
-    assert_template_result('', '{{ foo }}', { 'foo' => [[nil]] })
-  end
-
   def test_dynamic_find_var
     assert_template_result('bar', '{{ [key] }}', { 'key' => 'foo', 'foo' => 'bar' })
   end

test/test_helper.rb

@@ -13,7 +13,12 @@ if (env_mode = ENV['LIQUID_PARSER_MODE'])
   puts "-- #{env_mode.upcase} ERROR MODE"
   mode = env_mode.to_sym
 end
-Liquid::Environment.default.error_mode = mode
+Liquid::Template.error_mode = mode
+
+if ENV['LIQUID_C'] == '1'
+  puts "-- LIQUID C"
+  require 'liquid/c'
+end
 
 if Minitest.const_defined?('Test')
   # We're on Minitest 5+. Nothing to do here.
@@ -83,11 +88,11 @@ module Minitest
     end
 
     def with_error_mode(mode)
-      old_mode = Liquid::Environment.default.error_mode
-      Liquid::Environment.default.error_mode = mode
+      old_mode = Liquid::Template.error_mode
+      Liquid::Template.error_mode = mode
       yield
     ensure
-      Liquid::Environment.default.error_mode = old_mode
+      Liquid::Template.error_mode = old_mode
     end
 
     def with_custom_tag(tag_name, tag_class, &block)

test/unit/block_unit_test.rb

@@ -32,12 +32,6 @@ 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)

test/unit/eager_optimize_test.rb

@@ -1,186 +0,0 @@
-# frozen_string_literal: true
-
-require 'test_helper'
-
-class EagerOptimizeTest < Minitest::Test
-  include Liquid
-
-  def test_remove_empty_blocks
-    source = <<~LIQUID.gsub(/\n/, '')
-      {% for i in (1..1000000) %}
-      {% endfor %}
-    LIQUID
-
-    template = Liquid::Template.parse(source, eager_optimize: true)
-    assert_equal(0, total_node_count(template))
-  end
-
-  def test_remove_false_if_block
-    source = <<~LIQUID.gsub(/\n/, '')
-      {% if false %}
-        {% if true %}
-          {% if true %}
-            {% if true %}
-              {{ "Hello world!" }}
-            {% endif %}
-          {% endif %}
-        {% endif %}
-      {% endif %}
-    LIQUID
-
-    template = Liquid::Template.parse(source, eager_optimize: true)
-    assert_equal(0, total_node_count(template))
-
-    source = <<~LIQUID.gsub(/\n/, '')
-      {% if false %}
-        {% for i in (1..1000000) %}
-          {{ "Hello world!" }}
-        {% endfor %}
-      {% endif %}
-    LIQUID
-
-    template = Liquid::Template.parse(source, eager_optimize: true)
-    assert_equal(0, total_node_count(template))
-  end
-
-  def test_remove_multiple_false_if_block
-    source = <<~LIQUID.gsub(/\n/, '')
-      {% if false %}
-        {% if true %}
-          {% if true %}
-            {% if true %}
-              {{ "Hello world!" }}
-            {% endif %}
-          {% endif %}
-        {% endif %}
-      {% endif %}
-    LIQUID
-
-    template = Liquid::Template.parse(source, eager_optimize: true)
-    assert_equal(0, total_node_count(template))
-  end
-
-  def test_merge_if_blocks
-    # for now, work with consecutive if blocks without any String nodes in between
-    source = <<~LIQUID.gsub(/\n/, '')
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if foo == 2 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if foo == 3 %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::If], source, { "foo" => nil })
-    assert_optimization([Liquid::If], source, { "foo" => 1 })
-    assert_optimization([Liquid::If], source, { "foo" => 2 })
-    assert_optimization([Liquid::If], source, { "foo" => 5 })
-
-    source = <<~LIQUID.gsub(/\n/, '')
-      {% assign bar = "application" %}
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if foo == 2 and bar contains "app" %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if 3 == foo and bar == "application" %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::Assign, Liquid::If], source)
-  end
-
-  def test_does_not_merge_if_blocks
-    assert_optimization([Liquid::If, Liquid::If], <<~LIQUID.gsub(/\n/, ''))
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if k == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::If, Liquid::If], <<~LIQUID.gsub(/\n/, ''))
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::If, Liquid::If], <<~LIQUID.gsub(/\n/, ''))
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if a == foo %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::If, Liquid::If], <<~LIQUID.gsub(/\n/, ''))
-      {% if foo %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if foo %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::If, Liquid::If], <<~LIQUID.gsub(/\n/, ''))
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if foo >= 1 %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-
-    assert_optimization([Liquid::If, Liquid::If], <<~LIQUID.gsub(/\n/, ''))
-      {% if foo == 1 %}
-        foo: {{ foo }}
-      {% endif %}
-      {% if 1  %}
-        foo: {{ foo }}
-      {% endif %}
-    LIQUID
-  end
-
-  private
-
-  def assert_optimization(expected, source, context = { "foo" => 1 })
-    template = Template.parse(source, eager_optimize: true)
-    assert_equal(expected, template.root.nodelist.map(&:class),)
-
-    baseline_template = Template.parse(source, eager_optimize: false)
-
-    assert_equal(
-      baseline_template.render(context),
-      template.render(context),
-    )
-  end
-
-  def total_node_count(template)
-    root = template.root
-    children = root.nodelist
-    count = 0
-
-    while children.any?
-      next_children = []
-
-      children.each do |node|
-        count += 1 unless node.is_a?(Liquid::BlockBody)
-        next_children.concat(node.nodelist) if node.respond_to?(:nodelist) && node.nodelist
-      end
-
-      children = next_children
-    end
-
-    count
-  end
-end

test/unit/lexer_unit_test.rb

@@ -6,134 +6,48 @@ class LexerUnitTest < Minitest::Test
   include Liquid
 
   def test_strings
-    assert_equal(
-      [[:string, %('this is a test""')], [:string, %("wat 'lol'")], [:end_of_string]],
-      tokenize(%( 'this is a test""' "wat 'lol'")),
-    )
+    tokens = Lexer.new(%( 'this is a test""' "wat 'lol'")).tokenize
+    assert_equal([[:string, %('this is a test""')], [:string, %("wat 'lol'")], [:end_of_string]], tokens)
   end
 
   def test_integer
-    assert_equal(
-      [[:id, 'hi'], [:number, '50'], [:end_of_string]],
-      tokenize('hi 50'),
-    )
+    tokens = Lexer.new('hi 50').tokenize
+    assert_equal([[:id, 'hi'], [:number, '50'], [:end_of_string]], tokens)
   end
 
   def test_float
-    assert_equal(
-      [[:id, 'hi'], [:number, '5.0'], [:end_of_string]],
-      tokenize('hi 5.0'),
-    )
+    tokens = Lexer.new('hi 5.0').tokenize
+    assert_equal([[:id, 'hi'], [:number, '5.0'], [:end_of_string]], tokens)
   end
 
   def test_comparison
-    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
+    tokens = Lexer.new('== <> contains ').tokenize
+    assert_equal([[:comparison, '=='], [:comparison, '<>'], [:comparison, 'contains'], [:end_of_string]], tokens)
   end
 
   def test_specials
-    assert_equal(
-      [[:pipe, '|'], [:dot, '.'], [:colon, ':'], [:end_of_string]],
-      tokenize('| .:'),
-    )
-
-    assert_equal(
-      [[:open_square, '['], [:comma, ','], [:close_square, ']'], [:end_of_string]],
-      tokenize('[,]'),
-    )
+    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)
   end
 
   def test_fancy_identifiers
-    assert_equal([[:id, 'hi'], [:id, 'five?'], [:end_of_string]], tokenize('hi five?'))
+    tokens = Lexer.new('hi five?').tokenize
+    assert_equal([[:id, 'hi'], [:id, 'five?'], [:end_of_string]], tokens)
 
-    assert_equal([[:number, '2'], [:id, 'foo'], [:end_of_string]], tokenize('2foo'))
+    tokens = Lexer.new('2foo').tokenize
+    assert_equal([[:number, '2'], [:id, 'foo'], [:end_of_string]], tokens)
   end
 
   def test_whitespace
-    assert_equal(
-      [[:id, 'five'], [:pipe, '|'], [:comparison, '=='], [:end_of_string]],
-      tokenize("five|\n\t =="),
-    )
+    tokens = Lexer.new("five|\n\t ==").tokenize
+    assert_equal([[:id, 'five'], [:pipe, '|'], [:comparison, '=='], [:end_of_string]], tokens)
   end
 
   def test_unexpected_character
     assert_raises(SyntaxError) do
-      tokenize("%")
+      Lexer.new("%").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/strainer_factory_unit_test.rb

@@ -2,7 +2,7 @@
 
 require 'test_helper'
 
-class EnvironmentFilterTest < Minitest::Test
+class StrainerFactoryUnitTest < Minitest::Test
   include Liquid
 
   module AccessScopeFilters
@@ -16,6 +16,8 @@ class EnvironmentFilterTest < Minitest::Test
     private :private_filter
   end
 
+  StrainerFactory.add_global_filter(AccessScopeFilters)
+
   module LateAddedFilter
     def late_added_filter(_input)
       "filtered"
@@ -23,28 +25,24 @@ class EnvironmentFilterTest < Minitest::Test
   end
 
   def setup
-    @environment = Liquid::Environment.build do |env|
-      env.register_filter(AccessScopeFilters)
-    end
-
-    @context = Context.build(environment: @environment)
+    @context = Context.build
   end
 
   def test_strainer
-    strainer = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@context)
     assert_equal(5, strainer.invoke('size', 'input'))
     assert_equal("public", strainer.invoke("public_filter"))
   end
 
   def test_stainer_raises_argument_error
-    strainer = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@context)
     assert_raises(Liquid::ArgumentError) do
       strainer.invoke("public_filter", 1)
     end
   end
 
   def test_stainer_argument_error_contains_backtrace
-    strainer = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@context)
 
     exception = assert_raises(Liquid::ArgumentError) do
       strainer.invoke("public_filter", 1)
@@ -59,7 +57,7 @@ class EnvironmentFilterTest < Minitest::Test
   end
 
   def test_strainer_only_invokes_public_filter_methods
-    strainer = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@context)
     assert_equal(false, strainer.class.invokable?('__test__'))
     assert_equal(false, strainer.class.invokable?('test'))
     assert_equal(false, strainer.class.invokable?('instance_eval'))
@@ -68,18 +66,18 @@ class EnvironmentFilterTest < Minitest::Test
   end
 
   def test_strainer_returns_nil_if_no_filter_method_found
-    strainer = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@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 = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@context)
     assert_equal("password", strainer.invoke("undef_the_method", "password"))
   end
 
   def test_strainer_only_allows_methods_defined_in_filters
-    strainer = @environment.create_strainer(@context)
+    strainer = StrainerFactory.create(@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"))
@@ -88,9 +86,7 @@ class EnvironmentFilterTest < Minitest::Test
   def test_strainer_uses_a_class_cache_to_avoid_method_cache_invalidation
     a = Module.new
     b = Module.new
-
-    strainer = @environment.create_strainer(@context, [a, b])
-
+    strainer = StrainerFactory.create(@context, [a, b])
     assert_kind_of(StrainerTemplate, strainer)
     assert_kind_of(a, strainer)
     assert_kind_of(b, strainer)
@@ -98,10 +94,8 @@ class EnvironmentFilterTest < Minitest::Test
   end
 
   def test_add_global_filter_clears_cache
-    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'))
+    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'))
   end
 end

test/unit/strainer_template_unit_test.rb

@@ -25,13 +25,11 @@ class StrainerTemplateUnitTest < Minitest::Test
   end
 
   def test_add_filter_raises_when_module_privately_overrides_registered_public_methods
-    error = assert_raises(Liquid::MethodOverrideError) do
-      Liquid::Environment.build do |env|
-        env.register_filter(PublicMethodOverrideFilter)
-        env.register_filter(PrivateMethodOverrideFilter)
-      end
-    end
+    strainer = Context.new.strainer
 
+    error = assert_raises(Liquid::MethodOverrideError) do
+      strainer.class.add_filter(PrivateMethodOverrideFilter)
+    end
     assert_equal('Liquid error: Filter overrides registered public methods as non public: public_filter', error.message)
   end
 
@@ -44,13 +42,11 @@ class StrainerTemplateUnitTest < Minitest::Test
   end
 
   def test_add_filter_raises_when_module_overrides_registered_public_method_as_protected
-    error = assert_raises(Liquid::MethodOverrideError) do
-      Liquid::Environment.build do |env|
-        env.register_filter(PublicMethodOverrideFilter)
-        env.register_filter(ProtectedMethodOverrideFilter)
-      end
-    end
+    strainer = Context.new.strainer
 
+    error = assert_raises(Liquid::MethodOverrideError) do
+      strainer.class.add_filter(ProtectedMethodOverrideFilter)
+    end
     assert_equal('Liquid error: Filter overrides registered public methods as non public: public_filter', error.message)
   end
 

test/unit/template_unit_test.rb

@@ -20,12 +20,50 @@ class TemplateUnitTest < Minitest::Test
     assert_equal(fixture("en_locale.yml"), locale.path)
   end
 
+  def test_with_cache_classes_tags_returns_the_same_class
+    original_cache_setting = Liquid.cache_classes
+    Liquid.cache_classes   = true
+
+    original_klass = Class.new
+    Object.send(:const_set, :CustomTag, original_klass)
+    Template.register_tag('custom', CustomTag)
+
+    Object.send(:remove_const, :CustomTag)
+
+    new_klass = Class.new
+    Object.send(:const_set, :CustomTag, new_klass)
+
+    assert(Template.tags['custom'].equal?(original_klass))
+  ensure
+    Object.send(:remove_const, :CustomTag)
+    Liquid.cache_classes = original_cache_setting
+  end
+
+  def test_without_cache_classes_tags_reloads_the_class
+    original_cache_setting = Liquid.cache_classes
+    Liquid.cache_classes   = false
+
+    original_klass = Class.new
+    Object.send(:const_set, :CustomTag, original_klass)
+    with_custom_tag('custom', CustomTag) do
+      Object.send(:remove_const, :CustomTag)
+
+      new_klass = Class.new
+      Object.send(:const_set, :CustomTag, new_klass)
+
+      assert(Template.tags['custom'].equal?(new_klass))
+    end
+  ensure
+    Object.send(:remove_const, :CustomTag)
+    Liquid.cache_classes = original_cache_setting
+  end
+
   class FakeTag; end
 
   def test_tags_can_be_looped_over
     with_custom_tag('fake', FakeTag) do
       result = Template.tags.map { |name, klass| [name, klass] }
-      assert(result.include?(["fake", TemplateUnitTest::FakeTag]))
+      assert(result.include?(["fake", "TemplateUnitTest::FakeTag"]))
     end
   end