refactor: Reduce maximum block nesting in Liquid::BlockBody#parse

2026-01-02 00:05:42 +03:00 · 2017-10-17 18:14:45 -04:00
64 changed files with 271 additions and 1716 deletions
--- a/.github/probots.yml
+++ b/.github/probots.yml
@@ -1,2 +0,0 @@
-enabled:
-  - cla
--- a/.gitignore
+++ b/.gitignore
@@ -7,4 +7,3 @@ pkg
 .ruby-version
 Gemfile.lock
 .bundle
-.byebug_history
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,6 +1,4 @@
-inherit_from:
-  - .rubocop_todo.yml
-  - ./.rubocop_todo.yml
+inherit_from: ./.rubocop_todo.yml

 AllCops:
  Exclude:
@@ -31,8 +29,8 @@ Lint/ParenthesesAsGroupedExpression:
 Lint/UnusedBlockArgument:
  Enabled: false

-Layout/EndAlignment:
-  EnforcedStyleAlignWith: variable
+Lint/EndAlignment:
+  AlignWith: variable

 Lint/UnusedMethodArgument:
  Enabled: false
@@ -61,10 +59,10 @@ Style/BracesAroundHashParameters:
 Style/NumericLiterals:
  Enabled: false

-Layout/SpaceInsideArrayLiteralBrackets:
+Style/SpaceInsideBrackets:
  Enabled: false

-Layout/SpaceBeforeBlockBraces:
+Style/SpaceBeforeBlockBraces:
  Enabled: false

 Style/Documentation:
@@ -73,22 +71,19 @@ Style/Documentation:
 Style/ClassAndModuleChildren:
  Enabled: false

-Style/TrailingCommaInArrayLiteral:
+Style/TrailingComma:
  Enabled: false

-Style/TrailingCommaInHashLiteral:
-  Enabled: false
-
-Layout/IndentHash:
+Style/IndentHash:
  EnforcedStyle: consistent

 Style/FormatString:
  Enabled: false

-Layout/AlignParameters:
+Style/AlignParameters:
  EnforcedStyle: with_fixed_indentation

-Layout/MultilineOperationIndentation:
+Style/MultilineOperationIndentation:
  EnforcedStyle: indented

 Style/IfUnlessModifier:
@@ -97,7 +92,7 @@ Style/IfUnlessModifier:
 Style/RaiseArgs:
  Enabled: false

-Style/PreferredHashMethods:
+Style/DeprecatedHashMethods:
  Enabled: false

 Style/RegexpLiteral:
@@ -109,10 +104,10 @@ Style/SymbolLiteral:
 Performance/Count:
  Enabled: false

-Naming/ConstantName:
+Style/ConstantName:
  Enabled: false

-Layout/CaseIndentation:
+Style/CaseIndentation:
  Enabled: false

 Style/ClassVars:
@@ -126,7 +121,3 @@ Style/TrivialAccessors:

 Style/WordArray:
  Enabled: false
-
-Naming/MethodName:
-  Exclude:
-    - 'example/server/liquid_servlet.rb'
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,260 +1,72 @@
-# This configuration was generated by
-# `rubocop --auto-gen-config`
-# on 2019-04-22 19:11:24 -0400 using RuboCop version 0.53.0.
+# This configuration was generated by `rubocop --auto-gen-config`
+# on 2015-06-08 18:16:16 +0000 using RuboCop version 0.32.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.

-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: Include, TreatCommentsAsGroupSeparators.
-# Include: **/*.gemspec
-Gemspec/OrderedDependencies:
-  Exclude:
-    - 'liquid.gemspec'
-
 # Offense count: 5
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: auto_detection, squiggly, active_support, powerpack, unindent
-Layout/IndentHeredoc:
-  Exclude:
-    - 'test/integration/tags/for_tag_test.rb'
-    - 'test/integration/trim_mode_test.rb'
-
-# Offense count: 6
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: symmetrical, new_line, same_line
-Layout/MultilineMethodCallBraceLayout:
-  Exclude:
-    - 'test/integration/error_handling_test.rb'
-    - 'test/unit/strainer_unit_test.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: runtime_error, standard_error
-Lint/InheritException:
-  Exclude:
-    - 'lib/liquid/interrupts.rb'
-
-# Offense count: 1
-# Configuration parameters: CheckForMethodsWithNoSideEffects.
-Lint/Void:
-  Exclude:
-    - 'lib/liquid/parse_context.rb'
+Lint/NestedMethodDefinition:
+  Enabled: false

 # Offense count: 53
 Metrics/AbcSize:
-  Max: 56
+  Max: 58

 # Offense count: 12
 Metrics/CyclomaticComplexity:
-  Max: 13
+  Max: 15

-# Offense count: 112
+# Offense count: 553
+# Configuration parameters: AllowURI, URISchemes.
+Metrics/LineLength:
+  Max: 294
+
+# Offense count: 77
 # Configuration parameters: CountComments.
 Metrics/MethodLength:
-  Max: 38
+  Max: 46

-# Offense count: 8
+# Offense count: 6
 Metrics/PerceivedComplexity:
-  Max: 11
+  Max: 13

-# Offense count: 52
-# Configuration parameters: Blacklist.
-# Blacklist: END, (?-mix:EO[A-Z]{1})
-Naming/HeredocDelimiterNaming:
-  Exclude:
-    - 'test/integration/assign_test.rb'
-    - 'test/integration/capture_test.rb'
-    - 'test/integration/trim_mode_test.rb'
-
-# Offense count: 23
-# Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
-# AllowedNames: io, id
-Naming/UncommunicativeMethodParamName:
-  Exclude:
-    - 'example/server/example_servlet.rb'
-    - 'lib/liquid/condition.rb'
-    - 'lib/liquid/context.rb'
-    - 'lib/liquid/standardfilters.rb'
-    - 'lib/liquid/tags/if.rb'
-    - 'lib/liquid/utils.rb'
-    - 'lib/liquid/variable.rb'
-    - 'test/integration/filter_test.rb'
-    - 'test/integration/standard_filter_test.rb'
-    - 'test/integration/tags/for_tag_test.rb'
-    - 'test/integration/template_test.rb'
-    - 'test/unit/condition_unit_test.rb'
-
-# Offense count: 12
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: prefer_alias, prefer_alias_method
-Style/Alias:
-  Exclude:
-    - 'lib/liquid/drop.rb'
-    - 'lib/liquid/i18n.rb'
-    - 'lib/liquid/profiler/hooks.rb'
-    - 'lib/liquid/standardfilters.rb'
-    - 'lib/liquid/tag.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'lib/liquid/variable.rb'
-
-# Offense count: 22
-Style/CommentedKeyword:
+# Offense count: 1
+Style/AccessorMethodName:
  Enabled: false

 # Offense count: 1
 # Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SingleLineConditionsOnly, IncludeTernaryExpressions.
-# SupportedStyles: assign_to_condition, assign_inside_condition
-Style/ConditionalAssignment:
-  Exclude:
-    - 'lib/liquid/errors.rb'
-
-# Offense count: 1
-Style/DateTime:
-  Exclude:
-    - 'test/unit/context_unit_test.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/EmptyCaseCondition:
-  Exclude:
-    - 'lib/liquid/block_body.rb'
-    - 'lib/liquid/lexer.rb'
-
-# Offense count: 5
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: compact, expanded
-Style/EmptyMethod:
-  Exclude:
-    - 'lib/liquid/tag.rb'
-    - 'lib/liquid/tags/comment.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'test/integration/tags/include_tag_test.rb'
-    - 'test/unit/context_unit_test.rb'
+Style/ClosingParenthesisIndentation:
+  Enabled: false

 # Offense count: 3
-# Cop supports --auto-correct.
-Style/Encoding:
-  Exclude:
-    - 'lib/liquid/version.rb'
-    - 'liquid.gemspec'
-    - 'test/integration/standard_filter_test.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/ExpandPathArguments:
-  Exclude:
-    - 'Rakefile'
-    - 'liquid.gemspec'
-
-# Offense count: 7
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: annotated, template, unannotated
-Style/FormatStringToken:
-  Exclude:
-    - 'test/integration/filter_test.rb'
-    - 'test/integration/hash_ordering_test.rb'
-
-# Offense count: 14
 # Configuration parameters: MinBodyLength.
 Style/GuardClause:
-  Exclude:
-    - 'lib/liquid/condition.rb'
-    - 'lib/liquid/lexer.rb'
-    - 'lib/liquid/strainer.rb'
-    - 'lib/liquid/tags/assign.rb'
-    - 'lib/liquid/tags/capture.rb'
-    - 'lib/liquid/tags/case.rb'
-    - 'lib/liquid/tags/for.rb'
-    - 'lib/liquid/tags/include.rb'
-    - 'lib/liquid/tags/raw.rb'
-    - 'lib/liquid/tags/table_row.rb'
-    - 'lib/liquid/variable.rb'
-    - 'test/unit/tokenizer_unit_test.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, MinBodyLength.
-# SupportedStyles: skip_modifier_ifs, always
-Style/Next:
-  Exclude:
-    - 'lib/liquid/tags/for.rb'
+  Enabled: false

 # Offense count: 4
-# Cop supports --auto-correct.
-# Configuration parameters: AutoCorrect, EnforcedStyle.
-# SupportedStyles: predicate, comparison
-Style/NumericPredicate:
-  Exclude:
-    - 'spec/**/*'
-    - 'lib/liquid/context.rb'
-    - 'lib/liquid/forloop_drop.rb'
-    - 'lib/liquid/standardfilters.rb'
-    - 'lib/liquid/tablerowloop_drop.rb'
-
-# Offense count: 14
-# Cop supports --auto-correct.
-# Configuration parameters: PreferredDelimiters.
-Style/PercentLiteralDelimiters:
-  Exclude:
-    - 'lib/liquid/tags/if.rb'
-    - 'liquid.gemspec'
-    - 'test/integration/assign_test.rb'
-    - 'test/integration/standard_filter_test.rb'
+# Configuration parameters: EnforcedStyle, SupportedStyles.
+Style/MethodName:
+  Enabled: false

 # Offense count: 1
-# Cop supports --auto-correct.
-Style/RedundantSelf:
-  Exclude:
-    - 'lib/liquid/strainer.rb'
+Style/MultilineBlockChain:
+  Enabled: false

-# Offense count: 9
+# Offense count: 2
+# Configuration parameters: EnforcedStyle, MinBodyLength, SupportedStyles.
+Style/Next:
+  Enabled: false
+
+# Offense count: 7
 # Cop supports --auto-correct.
 # Configuration parameters: AllowAsExpressionSeparator.
 Style/Semicolon:
-  Exclude:
-    - 'test/integration/error_handling_test.rb'
-    - 'test/integration/template_test.rb'
-    - 'test/unit/context_unit_test.rb'
-
-# Offense count: 7
-# Cop supports --auto-correct.
-# Configuration parameters: MinSize.
-# SupportedStyles: percent, brackets
-Style/SymbolArray:
-  EnforcedStyle: brackets
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, AllowSafeAssignment.
-# SupportedStyles: require_parentheses, require_no_parentheses, require_parentheses_when_complex
-Style/TernaryParentheses:
-  Exclude:
-    - 'lib/liquid/context.rb'
-    - 'lib/liquid/utils.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/UnneededPercentQ:
-  Exclude:
-    - 'test/integration/error_handling_test.rb'
+  Enabled: false

 # Offense count: 1
 # Cop supports --auto-correct.
+# Configuration parameters: MaxLineLength.
 Style/WhileUntilModifier:
-  Exclude:
-    - 'lib/liquid/tags/case.rb'
-
-# Offense count: 648
-# Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
-# URISchemes: http, https
-Metrics/LineLength:
-  Max: 294
+  Enabled: false
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,32 +3,27 @@ language: ruby
 rvm:
  - 2.1
  - 2.2
-  - 2.3
-  - 2.4
-  - 2.5
-  - &latest_ruby 2.6
+  - 2.3.3
  - ruby-head
  - jruby-head
 #  - rbx-2

+sudo: false
+
 addons:
  apt:
    packages:
    - libgmp3-dev

 matrix:
-  include:
-    - rvm: *latest_ruby
-      script: bundle exec rake memory_profile:run
-      name: Profiling Memory Usage
  allow_failures:
-    - rvm: ruby-head
    - rvm: jruby-head

 install:
+  - gem install rainbow -v 2.2.1
  - bundle install

-script: bundle exec rake
+script: "bundle exec rake"

 notifications:
  disable: true
--- a/15
+++ b/15
@@ -1,24 +1,17 @@
 source 'https://rubygems.org'
-git_source(:github) do |repo_name|
-  "https://github.com/#{repo_name}.git"
-end

 gemspec

+gem 'stackprof', platforms: :mri
+
 group :benchmark, :test do
  gem 'benchmark-ips'
-  gem 'memory_profiler'
-  gem 'terminal-table'
-
-  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ } do
-    gem 'stackprof'
-  end
 end

 group :test do
-  gem 'rubocop', '~> 0.53.0'
+  gem 'rubocop', '0.34.2'

  platform :mri do
-    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'liquid-tag'
+    gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'bd53db95de3d44d631e7c5a267c3d934e66107dd'
  end
 end
--- a/History.md
+++ b/History.md
@@ -1,58 +1,5 @@
 # Liquid Change Log

-## 4.0.3 / 2019-03-12
-
-### Fixed
-* Fix break and continue tags inside included templates in loops (#1072) [Justin Li]
-
-## 4.0.2 / 2019-03-08
-
-### Changed
-* Add `where` filter (#1026) [Samuel Doiron]
-* Add `ParseTreeVisitor` to iterate the Liquid AST (#1025) [Stephen Paul Weber]
-* Improve `strip_html` performance (#1032) [printercu]
-
-### Fixed
-* Add error checking for invalid combinations of inputs to sort, sort_natural, where, uniq, map, compact filters (#1059) [Garland Zhang]
-* Validate the character encoding in url_decode (#1070) [Clayton Smith]
-
-## 4.0.1 / 2018-10-09
-
-### Changed
-* Add benchmark group in Gemfile (#855) [Jerry Liu]
-* Allow benchmarks to benchmark render by itself (#851) [Jerry Liu]
-* Avoid calling `line_number` on String node when rescuing a render error. (#860) [Dylan Thacker-Smith]
-* Avoid duck typing to detect whether to call render on a node. [Dylan Thacker-Smith]
-* Clarify spelling of `reversed` on `for` block tag (#843) [Mark Crossfield]
-* Replace recursion with loop to avoid potential stack overflow from malicious input (#891, #892) [Dylan Thacker-Smith]
-* Limit block tag nesting to 100 (#894) [Dylan Thacker-Smith]
-* Replace `assert_equal nil` with `assert_nil` (#895) [Dylan Thacker-Smith]
-* Remove Spy Gem (#896) [Dylan Thacker-Smith]
-* Add `collection_name` and `variable_name` reader to `For` block (#909)
-* Symbols render as strings (#920) [Justin Li]
-* Remove default value from Hash objects (#932) [Maxime Bedard]
-* Remove one level of nesting (#944) [Dylan Thacker-Smith]
-* Update Rubocop version (#952) [Justin Li]
-* Add `at_least` and `at_most` filters (#954, #958) [Nithin Bekal]
-* Add a regression test for a liquid-c trim mode bug (#972) [Dylan Thacker-Smith]
-* Use https rather than git protocol to fetch liquid-c [Dylan Thacker-Smith]
-* Add tests against Ruby 2.4 (#963) and 2.5 (#981)
-* Replace RegExp literals with constants (#988) [Ashwin Maroli]
-* Replace unnecessary `#each_with_index` with `#each` (#992) [Ashwin Maroli]
-* Improve the unexpected end delimiter message for block tags. (#1003) [Dylan Thacker-Smith]
-* Refactor and optimize rendering (#1005) [Christopher Aue]
-* Add installation instruction (#1006) [Ben Gift]
-* Remove Circle CI (#1010)
-* Rename deprecated `BigDecimal.new` to `BigDecimal` (#1024) [Koichi ITO]
-* Rename deprecated Rubocop name (#1027) [Justin Li]
-
-### Fixed
-* Handle `join` filter on non String joiners (#857) [Richard Monette]
-* Fix duplicate inclusion condition logic error of `Liquid::Strainer.add_filter` method (#861)
-* Fix `escape`, `url_encode`, `url_decode` not handling non-string values (#898) [Thierry Joyal]
-* Fix raise when variable is defined but nil when using `strict_variables` [Pascal Betz]
-* Fix `sort` and `sort_natural` to handle arrays with nils (#930) [Eric Chan]
-
 ## 4.0.0 / 2016-12-14 / branch "4-0-stable"

 ### Changed
--- a/README.md
+++ b/README.md
@@ -42,8 +42,6 @@ Liquid is a template engine which was written with very specific requirements:

 ## How to use Liquid

-Install Liquid by adding `gem 'liquid'` to your gemfile.
-
 Liquid supports a very simple API based around the Liquid::Template class.
 For standard use you can just pass it the content of a file and call render with a parameters hash.

--- a/9
+++ b/9
@@ -3,7 +3,7 @@ require 'rake/testtask'
 $LOAD_PATH.unshift File.expand_path("../lib", __FILE__)
 require "liquid/version"

-task default: [:test, :rubocop]
+task default: [:rubocop, :test]

 desc 'run test suite with default parser'
 Rake::TestTask.new(:base_test) do |t|
@@ -85,13 +85,6 @@ namespace :profile do
  end
 end

-namespace :memory_profile do
-  desc "Run memory profiler"
-  task :run do
-    ruby "./performance/memory_profile.rb"
-  end
-end
-
 desc "Run example"
 task :example do
  ruby "-w -d -Ilib example/server/server.rb"
--- a/circle.yml
+++ b/circle.yml
@@ -0,0 +1,3 @@
+machine:
+  ruby:
+    version: ruby-2.1
--- a/lib/liquid.rb
+++ b/lib/liquid.rb
@@ -45,7 +45,6 @@ module Liquid
 end

 require "liquid/version"
-require 'liquid/parse_tree_visitor'
 require 'liquid/lexer'
 require 'liquid/parser'
 require 'liquid/i18n'
--- a/lib/liquid/block.rb
+++ b/lib/liquid/block.rb
@@ -13,7 +13,6 @@ module Liquid
      end
    end

-    # For backwards compatibility
    def render(context)
      @body.render(context)
    end
@@ -27,12 +26,12 @@ module Liquid
    end

    def unknown_tag(tag, _params, _tokens)
-      if tag == 'else'.freeze
+      case tag
+      when 'else'.freeze
        raise SyntaxError.new(parse_context.locale.t("errors.syntax.unexpected_else".freeze,
          block_name: block_name))
-      elsif tag.start_with?('end'.freeze)
+      when 'end'.freeze
        raise SyntaxError.new(parse_context.locale.t("errors.syntax.invalid_delimiter".freeze,
-          tag: tag,
          block_name: block_name,
          block_delimiter: block_delimiter))
      else
--- a/lib/liquid/block_body.rb
+++ b/lib/liquid/block_body.rb
@@ -1,9 +1,7 @@
 module Liquid
  class BlockBody
-    LiquidTagToken = /\A\s*(\w+)\s*(.*?)\z/o
-    FullToken = /\A#{TagStart}#{WhitespaceControl}?(\s*)(\w+)(\s*)(.*?)#{WhitespaceControl}?#{TagEnd}\z/om
+    FullToken = /\A#{TagStart}#{WhitespaceControl}?\s*(\w+)\s*(.*?)#{WhitespaceControl}?#{TagEnd}\z/om
    ContentOfVariable = /\A#{VariableStart}#{WhitespaceControl}?(.*?)#{WhitespaceControl}?#{VariableEnd}\z/om
-    WhitespaceOrNothing = /\A\s*\z/
    TAGSTART = "{%".freeze
    VARSTART = "{{".freeze

@@ -14,42 +12,8 @@ module Liquid
      @blank = true
    end

-    def parse(tokenizer, parse_context, &block)
+    def parse(tokenizer, parse_context)
      parse_context.line_number = tokenizer.line_number
-
-      if tokenizer.for_liquid_tag
-        parse_for_liquid_tag(tokenizer, parse_context, &block)
-      else
-        parse_for_document(tokenizer, parse_context, &block)
-      end
-    end
-
-    private def parse_for_liquid_tag(tokenizer, parse_context)
-      while token = tokenizer.shift
-        unless token.empty? || token =~ WhitespaceOrNothing
-          unless token =~ LiquidTagToken
-            # line isn't empty but didn't match tag syntax, yield and let the
-            # caller raise a syntax error
-            return yield token, token
-          end
-          tag_name = $1
-          markup = $2
-          unless tag = registered_tags[tag_name]
-            # end parsing if we reach an unknown tag and let the caller decide
-            # determine how to proceed
-            return yield tag_name, markup
-          end
-          new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
-          @blank &&= new_tag.blank?
-          @nodelist << new_tag
-        end
-        parse_context.line_number = tokenizer.line_number
-      end
-
-      yield nil, nil
-    end
-
-    private def parse_for_document(tokenizer, parse_context, &block)
      while token = tokenizer.shift
        next if token.empty?
        case
@@ -58,20 +22,9 @@ module Liquid
          unless token =~ FullToken
            raise_missing_tag_terminator(token, parse_context)
          end
-          tag_name = $2
-          markup = $4
-
-          if parse_context.line_number
-            # newlines inside the tag should increase the line number,
-            # particularly important for multiline {% liquid %} tags
-            parse_context.line_number += $1.count("\n".freeze) + $3.count("\n".freeze)
-          end
-
-          if tag_name == 'liquid'.freeze
-            liquid_tag_tokenizer = Tokenizer.new(markup, line_number: parse_context.line_number, for_liquid_tag: true)
-            next parse_for_liquid_tag(liquid_tag_tokenizer, parse_context, &block)
-          end
-
+          tag_name = $1
+          markup = $2
+          # fetch the tag from registered blocks
          unless tag = registered_tags[tag_name]
            # end parsing if we reach an unknown tag and let the caller decide
            # determine how to proceed
@@ -90,7 +43,7 @@ module Liquid
          end
          parse_context.trim_whitespace = false
          @nodelist << token
-          @blank &&= !!(token =~ WhitespaceOrNothing)
+          @blank &&= !!(token =~ /\A\s*\z/)
        end
        parse_context.line_number = tokenizer.line_number
      end
@@ -113,57 +66,52 @@ module Liquid
    end

    def render(context)
-      render_to_output_buffer(context, '')
-    end
-
-    def render_to_output_buffer(context, output)
+      output = []
      context.resource_limits.render_score += @nodelist.length

-      idx = 0
-      while node = @nodelist[idx]
-        previous_output_size = output.bytesize
+      @nodelist.each do |token|
+        # Break out if we have any unhanded interrupts.
+        break if context.interrupt?

-        case node
-        when String
-          output << node
-        when Variable
-          render_node(context, output, node)
-        when Block
-          render_node(context, node.blank? ? '' : output, node)
-          break if context.interrupt? # might have happened in a for-block
-        when Continue, Break
+        begin
          # If we get an Interrupt that means the block must stop processing. An
          # Interrupt is any command that stops block execution such as {% break %}
          # or {% continue %}
-          context.push_interrupt(node.interrupt)
-          break
-        else # Other non-Block tags
-          render_node(context, output, node)
-          break if context.interrupt? # might have happened through an include
-        end
-        idx += 1
+          if token.is_a?(Continue) || token.is_a?(Break)
+            context.push_interrupt(token.interrupt)
+            break
+          end

-        raise_if_resource_limits_reached(context, output.bytesize - previous_output_size)
+          node_output = render_node(token, context)
+
+          unless token.is_a?(Block) && token.blank?
+            output << node_output
+          end
+        rescue MemoryError => e
+          raise e
+        rescue UndefinedVariable, UndefinedDropMethod, UndefinedFilter => e
+          context.handle_error(e, token.line_number)
+          output << nil
+        rescue ::StandardError => e
+          line_number = token.is_a?(String) ? nil : token.line_number
+          output << context.handle_error(e, line_number)
+        end
      end

-      output
+      output.join
    end

    private

-    def render_node(context, output, node)
-      node.render_to_output_buffer(context, output)
-    rescue UndefinedVariable, UndefinedDropMethod, UndefinedFilter => e
-      context.handle_error(e, node.line_number)
-    rescue ::StandardError => e
-      line_number = node.is_a?(String) ? nil : node.line_number
-      output << context.handle_error(e, line_number)
-    end
+    def render_node(node, context)
+      node_output = node.is_a?(String) ? node : node.render(context)
+      node_output = node_output.is_a?(Array) ? node_output.join : node_output.to_s

-    def raise_if_resource_limits_reached(context, length)
-      context.resource_limits.render_length += length
-      return unless context.resource_limits.reached?
-      raise MemoryError.new("Memory limits exceeded".freeze)
+      context.resource_limits.render_length += node_output.length
+      if context.resource_limits.reached?
+        raise MemoryError.new("Memory limits exceeded".freeze)
+      end
+      node_output
    end

    def create_variable(token, parse_context)
--- a/lib/liquid/condition.rb
+++ b/lib/liquid/condition.rb
@@ -29,7 +29,7 @@ module Liquid
      @@operators
    end

-    attr_reader :attachment, :child_condition
+    attr_reader :attachment
    attr_accessor :left, :operator, :right

    def initialize(left = nil, operator = nil, right = nil)
@@ -83,7 +83,7 @@ module Liquid

    protected

-    attr_reader :child_relation
+    attr_reader :child_relation, :child_condition

    private

@@ -128,15 +128,6 @@ module Liquid
        end
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [
-          @node.left, @node.right,
-          @node.child_condition, @node.attachment
-        ].compact
-      end
-    end
  end

  class ElseCondition < Condition
--- a/lib/liquid/expression.rb
+++ b/lib/liquid/expression.rb
@@ -19,26 +19,22 @@ module Liquid
      'false'.freeze => false,
      'blank'.freeze => MethodLiteral.new(:blank?, '').freeze,
      'empty'.freeze => MethodLiteral.new(:empty?, '').freeze
-    }.freeze
-
-    SINGLE_QUOTED_STRING = /\A'(.*)'\z/m
-    DOUBLE_QUOTED_STRING = /\A"(.*)"\z/m
-    INTEGERS_REGEX       = /\A(-?\d+)\z/
-    FLOATS_REGEX         = /\A(-?\d[\d\.]+)\z/
-    RANGES_REGEX         = /\A\((\S+)\.\.(\S+)\)\z/
+    }

    def self.parse(markup)
      if LITERALS.key?(markup)
        LITERALS[markup]
      else
        case markup
-        when SINGLE_QUOTED_STRING, DOUBLE_QUOTED_STRING
+        when /\A'(.*)'\z/m # Single quoted strings
          $1
-        when INTEGERS_REGEX
+        when /\A"(.*)"\z/m # Double quoted strings
+          $1
+        when /\A(-?\d+)\z/ # Integer and floats
          $1.to_i
-        when RANGES_REGEX
+        when /\A\((\S+)\.\.(\S+)\)\z/ # Ranges
          RangeLookup.parse($1, $2)
-        when FLOATS_REGEX
+        when /\A(-?\d[\d\.]+)\z/ # Floats
          $1.to_f
        else
          VariableLookup.parse(markup)
--- a/lib/liquid/i18n.rb
+++ b/lib/liquid/i18n.rb
@@ -26,7 +26,7 @@ module Liquid
    def interpolate(name, vars)
      name.gsub(/%\{(\w+)\}/) do
        # raise TranslationError, "Undefined key #{$1} for interpolation in translation #{name}"  unless vars[$1.to_sym]
-        (vars[$1.to_sym]).to_s
+        "#{vars[$1.to_sym]}"
      end
    end

--- a/lib/liquid/lexer.rb
+++ b/lib/liquid/lexer.rb
@@ -12,14 +12,13 @@ module Liquid
      ')'.freeze => :close_round,
      '?'.freeze => :question,
      '-'.freeze => :dash
-    }.freeze
+    }
    IDENTIFIER = /[a-zA-Z_][\w-]*\??/
    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)
@@ -29,7 +28,7 @@ module Liquid
      @output = []

      until @ss.eos?
-        @ss.skip(WHITESPACE_OR_NOTHING)
+        @ss.skip(/\s*/)
        break if @ss.eos?
        tok = case
        when t = @ss.scan(COMPARISON_OPERATOR) then [:comparison, t]
--- a/lib/liquid/locales/en.yml
+++ b/lib/liquid/locales/en.yml
@@ -14,7 +14,7 @@
      if: "Syntax Error in tag 'if' - Valid syntax: if [expression]"
      include: "Error in tag 'include' - Valid syntax: include '[template]' (with|for) [object|collection]"
      unknown_tag: "Unknown tag '%{tag}'"
-      invalid_delimiter: "'%{tag}' is not a valid delimiter for %{block_name} tags. use %{block_delimiter}"
+      invalid_delimiter: "'end' is not a valid delimiter for %{block_name} tags. use %{block_delimiter}"
      unexpected_else: "%{block_name} tag does not expect 'else' tag"
      unexpected_outer_tag: "Unexpected outer '%{tag}' tag"
      tag_termination: "Tag '%{token}' was not properly terminated with regexp: %{tag_end}"
--- a/lib/liquid/parse_tree_visitor.rb
+++ b/lib/liquid/parse_tree_visitor.rb
@@ -1,42 +0,0 @@
-# frozen_string_literal: true
-
-module Liquid
-  class ParseTreeVisitor
-    def self.for(node, callbacks = Hash.new(proc {}))
-      if defined?(node.class::ParseTreeVisitor)
-        node.class::ParseTreeVisitor
-      else
-        self
-      end.new(node, callbacks)
-    end
-
-    def initialize(node, callbacks)
-      @node = node
-      @callbacks = callbacks
-    end
-
-    def add_callback_for(*classes, &block)
-      callback = block
-      callback = ->(node, _) { yield node } if block.arity.abs == 1
-      callback = ->(_, _) { yield } if block.arity.zero?
-      classes.each { |klass| @callbacks[klass] = callback }
-      self
-    end
-
-    def visit(context = nil)
-      children.map do |node|
-        item, new_context = @callbacks[node.class].call(node, context)
-        [
-          item,
-          ParseTreeVisitor.for(node, @callbacks).visit(new_context || context)
-        ]
-      end
-    end
-
-    protected
-
-    def children
-      @node.respond_to?(:nodelist) ? Array(@node.nodelist) : []
-    end
-  end
-end
--- a/lib/liquid/parser.rb
+++ b/lib/liquid/parser.rb
@@ -44,14 +44,11 @@ module Liquid
      tok[0] == type
    end

-    SINGLE_TOKEN_EXPRESSION_TYPES = [:string, :number].freeze
-    private_constant :SINGLE_TOKEN_EXPRESSION_TYPES
-
    def expression
      token = @tokens[@p]
      if token[0] == :id
        variable_signature
-      elsif SINGLE_TOKEN_EXPRESSION_TYPES.include? token[0]
+      elsif [:string, :number].include? token[0]
        consume
      elsif token.first == :open_round
        consume
--- a/lib/liquid/profiler/hooks.rb
+++ b/lib/liquid/profiler/hooks.rb
@@ -1,8 +1,8 @@
 module Liquid
  class BlockBody
-    def render_node_with_profiling(context, output, node)
+    def render_node_with_profiling(node, context)
      Profiler.profile_node_render(node) do
-        render_node_without_profiling(context, output, node)
+        render_node_without_profiling(node, context)
      end
    end

@@ -11,13 +11,13 @@ module Liquid
  end

  class Include < Tag
-    def render_to_output_buffer_with_profiling(context, output)
+    def render_with_profiling(context)
      Profiler.profile_children(context.evaluate(@template_name_expr).to_s) do
-        render_to_output_buffer_without_profiling(context, output)
+        render_without_profiling(context)
      end
    end

-    alias_method :render_to_output_buffer_without_profiling, :render_to_output_buffer
-    alias_method :render_to_output_buffer, :render_to_output_buffer_with_profiling
+    alias_method :render_without_profiling, :render
+    alias_method :render, :render_with_profiling
  end
 end
--- a/lib/liquid/standardfilters.rb
+++ b/lib/liquid/standardfilters.rb
@@ -9,14 +9,8 @@ module Liquid
      '<'.freeze => '&lt;'.freeze,
      '"'.freeze => '&quot;'.freeze,
      "'".freeze => '&#39;'.freeze
-    }.freeze
+    }
    HTML_ESCAPE_ONCE_REGEXP = /["><']|&(?!([a-zA-Z]+|(#\d+));)/
-    STRIP_HTML_BLOCKS = Regexp.union(
-      /<script.*?<\/script>/m,
-      /<!--.*?-->/m,
-      /<style.*?<\/style>/m
-    )
-    STRIP_HTML_TAGS = /<.*?>/m

    # Return the size of an array or of an string
    def size(input)
@@ -52,12 +46,7 @@ module Liquid
    end

    def url_decode(input)
-      return if input.nil?
-
-      result = CGI.unescape(input.to_s)
-      raise Liquid::ArgumentError, "invalid byte sequence in #{result.encoding}" unless result.valid_encoding?
-
-      result
+      CGI.unescape(input.to_s) unless input.nil?
    end

    def slice(input, offset, length = nil)
@@ -79,7 +68,7 @@ module Liquid
      truncate_string_str = truncate_string.to_s
      l = length - truncate_string_str.length
      l = 0 if l < 0
-      input_str.length > length ? input_str[0...l].concat(truncate_string_str) : input_str
+      input_str.length > length ? input_str[0...l] + truncate_string_str : input_str
    end

    def truncatewords(input, words = 15, truncate_string = "...".freeze)
@@ -88,7 +77,7 @@ module Liquid
      words = Utils.to_integer(words)
      l = words - 1
      l = 0 if l < 0
-      wordlist.length > l ? wordlist[0..l].join(" ".freeze).concat(truncate_string.to_s) : input
+      wordlist.length > l ? wordlist[0..l].join(" ".freeze) + truncate_string.to_s : input
    end

    # Split input string into an array of substrings separated by given pattern.
@@ -114,9 +103,7 @@ module Liquid

    def strip_html(input)
      empty = ''.freeze
-      result = input.to_s.gsub(STRIP_HTML_BLOCKS, empty)
-      result.gsub!(STRIP_HTML_TAGS, empty)
-      result
+      input.to_s.gsub(/<script.*?<\/script>/m, empty).gsub(/<!--.*?-->/m, empty).gsub(/<style.*?<\/style>/m, empty).gsub(/<.*?>/m, empty)
    end

    # Remove all newlines from the string
@@ -133,18 +120,19 @@ module Liquid
    # provide optional property with which to sort an array of hashes or drops
    def sort(input, property = nil)
      ary = InputIterator.new(input)
-
-      return [] if ary.empty?
-
      if property.nil?
+        ary.sort
+      elsif ary.empty? # The next two cases assume a non-empty array.
+        []
+      elsif ary.first.respond_to?(:[]) && !ary.first[property].nil?
        ary.sort do |a, b|
-          nil_safe_compare(a, b)
-        end
-      elsif ary.all? { |el| el.respond_to?(:[]) }
-        begin
-          ary.sort { |a, b| nil_safe_compare(a[property], b[property]) }
-        rescue TypeError
-          raise_property_error(property)
+          a = a[property]
+          b = b[property]
+          if a && b
+            a <=> b
+          else
+            a ? -1 : 1
+          end
        end
      end
    end
@@ -154,40 +142,12 @@ module Liquid
    def sort_natural(input, property = nil)
      ary = InputIterator.new(input)

-      return [] if ary.empty?
-
      if property.nil?
-        ary.sort do |a, b|
-          nil_safe_casecmp(a, b)
-        end
-      elsif ary.all? { |el| el.respond_to?(:[]) }
-        begin
-          ary.sort { |a, b| nil_safe_casecmp(a[property], b[property]) }
-        rescue TypeError
-          raise_property_error(property)
-        end
-      end
-    end
-
-    # Filter the elements of an array to those with a certain property value.
-    # By default the target is any truthy value.
-    def where(input, property, target_value = nil)
-      ary = InputIterator.new(input)
-
-      if ary.empty?
+        ary.sort { |a, b| a.casecmp(b) }
+      elsif ary.empty? # The next two cases assume a non-empty array.
        []
-      elsif ary.first.respond_to?(:[]) && target_value.nil?
-        begin
-          ary.select { |item| item[property] }
-        rescue TypeError
-          raise_property_error(property)
-        end
-      elsif ary.first.respond_to?(:[])
-        begin
-          ary.select { |item| item[property] == target_value }
-        rescue TypeError
-          raise_property_error(property)
-        end
+      elsif ary.first.respond_to?(:[]) && !ary.first[property].nil?
+        ary.sort { |a, b| a[property].casecmp(b[property]) }
      end
    end

@@ -201,11 +161,7 @@ module Liquid
      elsif ary.empty? # The next two cases assume a non-empty array.
        []
      elsif ary.first.respond_to?(:[])
-        begin
-          ary.uniq { |a| a[property] }
-        rescue TypeError
-          raise_property_error(property)
-        end
+        ary.uniq{ |a| a[property] }
      end
    end

@@ -227,8 +183,6 @@ module Liquid
          r.is_a?(Proc) ? r.call : r
        end
      end
-    rescue TypeError
-      raise_property_error(property)
    end

    # Remove nils within an array
@@ -241,22 +195,20 @@ module Liquid
      elsif ary.empty? # The next two cases assume a non-empty array.
        []
      elsif ary.first.respond_to?(:[])
-        begin
-          ary.reject { |a| a[property].nil? }
-        rescue TypeError
-          raise_property_error(property)
-        end
+        ary.reject{ |a| a[property].nil? }
      end
    end

    # Replace occurrences of a string with another
    def replace(input, string, replacement = ''.freeze)
-      input.to_s.gsub(string.to_s, replacement.to_s)
+      replacement = replacement.to_s
+      input.to_s.gsub(string.to_s) { replacement }
    end

    # Replace the first occurrences of a string with another
    def replace_first(input, string, replacement = ''.freeze)
-      input.to_s.sub(string.to_s, replacement.to_s)
+      replacement = replacement.to_s
+      input.to_s.sub(string.to_s) { replacement }
    end

    # remove a substring
@@ -403,22 +355,6 @@ module Liquid
      raise Liquid::FloatDomainError, e.message
    end

-    def at_least(input, n)
-      min_value = Utils.to_number(n)
-
-      result = Utils.to_number(input)
-      result = min_value if min_value > result
-      result.is_a?(BigDecimal) ? result.to_f : result
-    end
-
-    def at_most(input, n)
-      max_value = Utils.to_number(n)
-
-      result = Utils.to_number(input)
-      result = max_value if max_value < result
-      result.is_a?(BigDecimal) ? result.to_f : result
-    end
-
    def default(input, default_value = ''.freeze)
      if !input || input.respond_to?(:empty?) && input.empty?
        default_value
@@ -429,31 +365,11 @@ module Liquid

    private

-    def raise_property_error(property)
-      raise Liquid::ArgumentError.new("cannot select the property '#{property}'")
-    end
-
    def apply_operation(input, operand, operation)
      result = Utils.to_number(input).send(operation, Utils.to_number(operand))
      result.is_a?(BigDecimal) ? result.to_f : result
    end

-    def nil_safe_compare(a, b)
-      if !a.nil? && !b.nil?
-        a <=> b
-      else
-        a.nil? ? 1 : -1
-      end
-    end
-
-    def nil_safe_casecmp(a, b)
-      if !a.nil? && !b.nil?
-        a.to_s.casecmp(b.to_s)
-      else
-        a.nil? ? 1 : -1
-      end
-    end
-
    class InputIterator
      include Enumerable

--- a/lib/liquid/tag.rb
+++ b/lib/liquid/tag.rb
@@ -5,8 +5,8 @@ module Liquid
    include ParserSwitching

    class << self
-      def parse(tag_name, markup, tokenizer, parse_context)
-        tag = new(tag_name, markup, parse_context)
+      def parse(tag_name, markup, tokenizer, options)
+        tag = new(tag_name, markup, options)
        tag.parse(tokenizer)
        tag
      end
@@ -36,14 +36,6 @@ module Liquid
      ''.freeze
    end

-    # For backwards compatibility with custom tags. In a future release, the semantics
-    # of the `render_to_output_buffer` method will become the default and the `render`
-    # method will be removed.
-    def render_to_output_buffer(context, output)
-      output << render(context)
-      output
-    end
-
    def blank?
      false
    end
--- a/lib/liquid/tags/assign.rb
+++ b/lib/liquid/tags/assign.rb
@@ -10,27 +10,21 @@ module Liquid
  class Assign < Tag
    Syntax = /(#{VariableSignature}+)\s*=\s*(.*)\s*/om

-    def self.syntax_error_translation_key
-      "errors.syntax.assign".freeze
-    end
-
-    attr_reader :to, :from
-
    def initialize(tag_name, markup, options)
      super
      if markup =~ Syntax
        @to = $1
        @from = Variable.new($2, options)
      else
-        raise SyntaxError.new(options[:locale].t(self.class.syntax_error_translation_key))
+        raise SyntaxError.new options[:locale].t("errors.syntax.assign".freeze)
      end
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      val = @from.render(context)
      context.scopes.last[@to] = val
      context.resource_limits.assign_score += assign_score_of(val)
-      output
+      ''.freeze
    end

    def blank?
@@ -41,7 +35,7 @@ module Liquid

    def assign_score_of(val)
      if val.instance_of?(String)
-        val.bytesize
+        val.length
      elsif val.instance_of?(Array) || val.instance_of?(Hash)
        sum = 1
        # Uses #each to avoid extra allocations.
@@ -51,12 +45,6 @@ module Liquid
        1
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [@node.from]
-      end
-    end
  end

  Template.register_tag('assign'.freeze, Assign)
--- a/lib/liquid/tags/capture.rb
+++ b/lib/liquid/tags/capture.rb
@@ -22,12 +22,11 @@ module Liquid
      end
    end

-    def render_to_output_buffer(context, output)
-      previous_output_size = output.bytesize
-      super
+    def render(context)
+      output = super
      context.scopes.last[@to] = output
-      context.resource_limits.assign_score += (output.bytesize - previous_output_size)
-      output
+      context.resource_limits.assign_score += output.length
+      ''.freeze
    end

    def blank?
--- a/lib/liquid/tags/case.rb
+++ b/lib/liquid/tags/case.rb
@@ -3,8 +3,6 @@ module Liquid
    Syntax     = /(#{QuotedFragment})/o
    WhenSyntax = /(#{QuotedFragment})(?:(?:\s+or\s+|\s*\,\s*)(#{QuotedFragment}.*))?/om

-    attr_reader :blocks, :left
-
    def initialize(tag_name, markup, options)
      super
      @blocks = []
@@ -38,21 +36,21 @@ module Liquid
      end
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      context.stack do
        execute_else_block = true

+        output = ''
        @blocks.each do |block|
          if block.else?
-            block.attachment.render_to_output_buffer(context, output) if execute_else_block
+            return block.attachment.render(context) if execute_else_block
          elsif block.evaluate(context)
            execute_else_block = false
-            block.attachment.render_to_output_buffer(context, output)
+            output << block.attachment.render(context)
          end
        end
+        output
      end
-
-      output
    end

    private
@@ -82,12 +80,6 @@ module Liquid
      block.attach(BlockBody.new)
      @blocks << block
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [@node.left] + @node.blocks
-      end
-    end
  end

  Template.register_tag('case'.freeze, Case)
--- a/lib/liquid/tags/comment.rb
+++ b/lib/liquid/tags/comment.rb
@@ -1,7 +1,7 @@
 module Liquid
  class Comment < Block
-    def render_to_output_buffer(_context, output)
-      output
+    def render(_context)
+      ''.freeze
    end

    def unknown_tag(_tag, _markup, _tokens)
--- a/lib/liquid/tags/cycle.rb
+++ b/lib/liquid/tags/cycle.rb
@@ -15,8 +15,6 @@ module Liquid
    SimpleSyntax = /\A#{QuotedFragment}+/o
    NamedSyntax  = /\A(#{QuotedFragment})\s*\:\s*(.*)/om

-    attr_reader :variables
-
    def initialize(tag_name, markup, options)
      super
      case markup
@@ -31,29 +29,18 @@ module Liquid
      end
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      context.registers[:cycle] ||= {}

      context.stack do
        key = context.evaluate(@name)
        iteration = context.registers[:cycle][key].to_i
-
-        val = context.evaluate(@variables[iteration])
-
-        if val.is_a?(Array)
-          val = val.join
-        elsif !val.is_a?(String)
-          val = val.to_s
-        end
-
-        output << val
-
+        result = context.evaluate(@variables[iteration])
        iteration += 1
        iteration  = 0 if iteration >= @variables.size
        context.registers[:cycle][key] = iteration
+        result
      end
-
-      output
    end

    private
@@ -64,12 +51,6 @@ module Liquid
        $1 ? Expression.parse($1) : nil
      end.compact
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        Array(@node.variables)
-      end
-    end
  end

  Template.register_tag('cycle', Cycle)
--- a/lib/liquid/tags/decrement.rb
+++ b/lib/liquid/tags/decrement.rb
@@ -23,12 +23,11 @@ module Liquid
      @variable = markup.strip
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      value = context.environments.first[@variable] ||= 0
      value -= 1
      context.environments.first[@variable] = value
-      output << value.to_s
-      output
+      value.to_s
    end
  end

--- a/lib/liquid/tags/echo.rb
+++ b/lib/liquid/tags/echo.rb
@@ -1,24 +0,0 @@
-module Liquid
-  # Echo outputs an expression
-  #
-  #   {% echo monkey %}
-  #   {% echo user.name %}
-  #
-  # This is identical to variable output syntax, like {{ foo }}, but works
-  # inside {% liquid %} tags. The full syntax is supported, including filters:
-  #
-  #   {% echo user | link %}
-  #
-  class Echo < Tag
-    def initialize(tag_name, markup, parse_context)
-      super
-      @variable = Variable.new(markup, parse_context)
-    end
-
-    def render(context)
-      @variable.render_to_output_buffer(context, '')
-    end
-  end
-
-  Template.register_tag('echo'.freeze, Echo)
-end
--- a/lib/liquid/tags/for.rb
+++ b/lib/liquid/tags/for.rb
@@ -46,7 +46,8 @@ module Liquid
  class For < Block
    Syntax = /\A(#{VariableSegment}+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/o

-    attr_reader :collection_name, :variable_name, :limit, :from
+    attr_reader :collection_name
+    attr_reader :variable_name

    def initialize(tag_name, markup, options)
      super
@@ -70,16 +71,14 @@ module Liquid
      @else_block = BlockBody.new
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      segment = collection_segment(context)

      if segment.empty?
-        render_else(context, output)
+        render_else(context)
      else
-        render_segment(context, output, segment)
+        render_segment(context, segment)
      end
-
-      output
    end

    protected
@@ -126,23 +125,14 @@ module Liquid
      from = if @from == :continue
        offsets[@name].to_i
      else
-        from_value = context.evaluate(@from)
-        if from_value.nil?
-          0
-        else
-          Utils.to_integer(from_value)
-        end
+        context.evaluate(@from).to_i
      end

      collection = context.evaluate(@collection_name)
      collection = collection.to_a if collection.is_a?(Range)

-      limit_value = context.evaluate(@limit)
-      to = if limit_value.nil?
-        nil
-      else
-        Utils.to_integer(limit_value) + from
-      end
+      limit = context.evaluate(@limit)
+      to = limit ? limit.to_i + from : nil

      segment = Utils.slice_collection(collection, from, to)
      segment.reverse! if @reversed
@@ -152,10 +142,12 @@ module Liquid
      segment
    end

-    def render_segment(context, output, segment)
+    def render_segment(context, segment)
      for_stack = context.registers[:for_stack] ||= []
      length = segment.length

+      result = ''
+
      context.stack do
        loop_vars = Liquid::ForloopDrop.new(@name, length, for_stack[-1])

@@ -164,9 +156,9 @@ module Liquid
        begin
          context['forloop'.freeze] = loop_vars

-          segment.each do |item|
+          segment.each_with_index do |item, index|
            context[@variable_name] = item
-            @for_block.render_to_output_buffer(context, output)
+            result << @for_block.render(context)
            loop_vars.send(:increment!)

            # Handle any interrupts if they exist.
@@ -181,7 +173,7 @@ module Liquid
        end
      end

-      output
+      result
    end

    def set_attribute(key, expr)
@@ -197,18 +189,8 @@ module Liquid
      end
    end

-    def render_else(context, output)
-      if @else_block
-        @else_block.render_to_output_buffer(context, output)
-      else
-        output
-      end
-    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        (super + [@node.limit, @node.from, @node.collection_name]).compact
-      end
+    def render_else(context)
+      @else_block ? @else_block.render(context) : ''.freeze
    end
  end

--- a/lib/liquid/tags/if.rb
+++ b/lib/liquid/tags/if.rb
@@ -12,9 +12,7 @@ module Liquid
  class If < Block
    Syntax = /(#{QuotedFragment})\s*([=!<>a-z_]+)?\s*(#{QuotedFragment})?/o
    ExpressionsAndOperators = /(?:\b(?:\s?and\s?|\s?or\s?)\b|(?:\s*(?!\b(?:\s?and\s?|\s?or\s?)\b)(?:#{QuotedFragment}|\S+)\s*)+)/o
-    BOOLEAN_OPERATORS = %w(and or).freeze
-
-    attr_reader :blocks
+    BOOLEAN_OPERATORS = %w(and or)

    def initialize(tag_name, markup, options)
      super
@@ -22,15 +20,15 @@ module Liquid
      push_block('if'.freeze, markup)
    end

-    def nodelist
-      @blocks.map(&:attachment)
-    end
-
    def parse(tokens)
      while parse_body(@blocks.last.attachment, tokens)
      end
    end

+    def nodelist
+      @blocks.map(&:attachment)
+    end
+
    def unknown_tag(tag, markup, tokens)
      if ['elsif'.freeze, 'else'.freeze].include?(tag)
        push_block(tag, markup)
@@ -39,16 +37,15 @@ module Liquid
      end
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      context.stack do
        @blocks.each do |block|
          if block.evaluate(context)
-            return block.attachment.render_to_output_buffer(context, output)
+            return block.attachment.render(context)
          end
        end
+        ''.freeze
      end
-
-      output
    end

    private
@@ -111,12 +108,6 @@ module Liquid
        Condition.new(a)
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        @node.blocks
-      end
-    end
  end

  Template.register_tag('if'.freeze, If)
--- a/lib/liquid/tags/ifchanged.rb
+++ b/lib/liquid/tags/ifchanged.rb
@@ -1,17 +1,16 @@
 module Liquid
  class Ifchanged < Block
-    def render_to_output_buffer(context, output)
+    def render(context)
      context.stack do
-        block_output = ''
-        super(context, block_output)
+        output = super

-        if block_output != context.registers[:ifchanged]
-          context.registers[:ifchanged] = block_output
-          output << block_output
+        if output != context.registers[:ifchanged]
+          context.registers[:ifchanged] = output
+          output
+        else
+          ''.freeze
        end
      end
-
-      output
    end
  end

--- a/lib/liquid/tags/include.rb
+++ b/lib/liquid/tags/include.rb
@@ -16,8 +16,6 @@ module Liquid
  class Include < Tag
    Syntax = /(#{QuotedFragment}+)(\s+(?:with|for)\s+(#{QuotedFragment}+))?/o

-    attr_reader :template_name_expr, :variable_name_expr, :attributes
-
    def initialize(tag_name, markup, options)
      super

@@ -42,7 +40,7 @@ module Liquid
    def parse(_tokens)
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      template_name = context.evaluate(@template_name_expr)
      raise ArgumentError.new(options[:locale].t("errors.argument.include")) unless template_name

@@ -66,21 +64,19 @@ module Liquid
          end

          if variable.is_a?(Array)
-            variable.each do |var|
+            variable.collect do |var|
              context[context_variable_name] = var
-              partial.render_to_output_buffer(context, output)
+              partial.render(context)
            end
          else
            context[context_variable_name] = variable
-            partial.render_to_output_buffer(context, output)
+            partial.render(context)
          end
        end
      ensure
        context.template_name = old_template_name
        context.partial = old_partial
      end
-
-      output
    end

    private
@@ -111,15 +107,6 @@ module Liquid

      file_system.read_template_file(context.evaluate(@template_name_expr))
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [
-          @node.template_name_expr,
-          @node.variable_name_expr
-        ] + @node.attributes.values
-      end
-    end
  end

  Template.register_tag('include'.freeze, Include)
--- a/lib/liquid/tags/increment.rb
+++ b/lib/liquid/tags/increment.rb
@@ -20,11 +20,10 @@ module Liquid
      @variable = markup.strip
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      value = context.environments.first[@variable] ||= 0
      context.environments.first[@variable] = value + 1
-      output << value.to_s
-      output
+      value.to_s
    end
  end

--- a/lib/liquid/tags/raw.rb
+++ b/lib/liquid/tags/raw.rb
@@ -22,9 +22,8 @@ module Liquid
      raise SyntaxError.new(parse_context.locale.t("errors.syntax.tag_never_closed".freeze, block_name: block_name))
    end

-    def render_to_output_buffer(_context, output)
-      output << @body
-      output
+    def render(_context)
+      @body
    end

    def nodelist
--- a/lib/liquid/tags/table_row.rb
+++ b/lib/liquid/tags/table_row.rb
@@ -2,8 +2,6 @@ module Liquid
  class TableRow < Block
    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)/o

-    attr_reader :variable_name, :collection_name, :attributes
-
    def initialize(tag_name, markup, options)
      super
      if markup =~ Syntax
@@ -18,7 +16,7 @@ module Liquid
      end
    end

-    def render_to_output_buffer(context, output)
+    def render(context)
      collection = context.evaluate(@collection_name) or return ''.freeze

      from = @attributes.key?('offset'.freeze) ? context.evaluate(@attributes['offset'.freeze]).to_i : 0
@@ -30,34 +28,25 @@ module Liquid

      cols = context.evaluate(@attributes['cols'.freeze]).to_i

-      output << "<tr class=\"row1\">\n"
+      result = "<tr class=\"row1\">\n"
      context.stack do
        tablerowloop = Liquid::TablerowloopDrop.new(length, cols)
        context['tablerowloop'.freeze] = tablerowloop

-        collection.each do |item|
+        collection.each_with_index do |item, index|
          context[@variable_name] = item

-          output << "<td class=\"col#{tablerowloop.col}\">"
-          super
-          output << '</td>'
+          result << "<td class=\"col#{tablerowloop.col}\">" << super << '</td>'

          if tablerowloop.col_last && !tablerowloop.last
-            output << "</tr>\n<tr class=\"row#{tablerowloop.row + 1}\">"
+            result << "</tr>\n<tr class=\"row#{tablerowloop.row + 1}\">"
          end

          tablerowloop.send(:increment!)
        end
      end
-
-      output << "</tr>\n"
-      output
-    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        super + @node.attributes.values + [@node.collection_name]
-      end
+      result << "</tr>\n"
+      result
    end
  end

--- a/lib/liquid/tags/unless.rb
+++ b/lib/liquid/tags/unless.rb
@@ -6,23 +6,23 @@ module Liquid
  #   {% unless x < 0 %} x is greater than zero {% endunless %}
  #
  class Unless < If
-    def render_to_output_buffer(context, output)
+    def render(context)
      context.stack do
        # First condition is interpreted backwards ( if not )
        first_block = @blocks.first
        unless first_block.evaluate(context)
-          return first_block.attachment.render_to_output_buffer(context, output)
+          return first_block.attachment.render(context)
        end

        # After the first condition unless works just like if
        @blocks[1..-1].each do |block|
          if block.evaluate(context)
-            return block.attachment.render_to_output_buffer(context, output)
+            return block.attachment.render(context)
          end
        end
-      end

-      output
+        ''.freeze
+      end
    end
  end

--- a/lib/liquid/template.rb
+++ b/lib/liquid/template.rb
@@ -50,7 +50,7 @@ module Liquid
      private

      def lookup_class(name)
-        Object.const_get(name)
+        name.split("::").reject(&:empty?).reduce(Object) { |scope, const| scope.const_get(const) }
      end
    end

@@ -187,12 +187,9 @@ module Liquid
        raise ArgumentError, "Expected Hash or Liquid::Context as parameter"
      end

-      output = nil
-
      case args.last
      when Hash
        options = args.pop
-        output = options[:output] if options[:output]

        registers.merge!(options[:registers]) if options[:registers].is_a?(Hash)

@@ -207,9 +204,10 @@ module Liquid
      begin
        # render the nodelist.
        # for performance reasons we get an array back here. join will make a string out of it.
-        with_profiling(context) do
-          @root.render_to_output_buffer(context, output || '')
+        result = with_profiling(context) do
+          @root.render(context)
        end
+        result.respond_to?(:join) ? result.join : result
      rescue Liquid::MemoryError => e
        context.handle_error(e)
      ensure
@@ -222,10 +220,6 @@ module Liquid
      render(*args)
    end

-    def render_to_output_buffer(context, output)
-      render(context, output: output)
-    end
-
    private

    def tokenize(source)
--- a/lib/liquid/tokenizer.rb
+++ b/lib/liquid/tokenizer.rb
@@ -1,31 +1,25 @@
 module Liquid
  class Tokenizer
-    attr_reader :line_number, :for_liquid_tag
+    attr_reader :line_number

-    def initialize(source, line_numbers = false, line_number: nil, for_liquid_tag: false)
+    def initialize(source, line_numbers = false)
      @source = source
-      @line_number = line_number || (line_numbers ? 1 : nil)
-      @for_liquid_tag = for_liquid_tag
+      @line_number = line_numbers ? 1 : nil
      @tokens = tokenize
    end

    def shift
-      token = @tokens.shift or return
-
-      if @line_number
-        @line_number += @for_liquid_tag ? 1 : token.count("\n")
-      end
-
+      token = @tokens.shift
+      @line_number += token.count("\n") if @line_number && token
      token
    end

    private

    def tokenize
+      @source = @source.source if @source.respond_to?(:source)
      return [] if @source.to_s.empty?

-      return @source.split("\n") if @for_liquid_tag
-
      tokens = @source.split(TemplateParser)

      # removes the rogue empty element at the beginning of the array
--- a/lib/liquid/utils.rb
+++ b/lib/liquid/utils.rb
@@ -46,11 +46,11 @@ module Liquid
    def self.to_number(obj)
      case obj
      when Float
-        BigDecimal(obj.to_s)
+        BigDecimal.new(obj.to_s)
      when Numeric
        obj
      when String
-        (obj.strip =~ /\A-?\d+\.\d+\z/) ? BigDecimal(obj) : obj.to_i
+        (obj.strip =~ /\A-?\d+\.\d+\z/) ? BigDecimal.new(obj) : obj.to_i
      else
        if obj.respond_to?(:to_number)
          obj.to_number
--- a/lib/liquid/variable.rb
+++ b/lib/liquid/variable.rb
@@ -10,16 +10,10 @@ module Liquid
  #   {{ user | link }}
  #
  class Variable
-    FilterMarkupRegex = /#{FilterSeparator}\s*(.*)/om
    FilterParser = /(?:\s+|#{QuotedFragment}|#{ArgumentSeparator})+/o
-    FilterArgsRegex = /(?:#{FilterArgumentSeparator}|#{ArgumentSeparator})\s*((?:\w+\s*\:\s*)?#{QuotedFragment})/o
-    JustTagAttributes = /\A#{TagAttributes}\z/o
-    MarkupWithQuotedFragment = /(#{QuotedFragment})(.*)/om
-
    attr_accessor :filters, :name, :line_number
    attr_reader :parse_context
    alias_method :options, :parse_context
-
    include ParserSwitching

    def initialize(markup, parse_context)
@@ -41,17 +35,17 @@ module Liquid

    def lax_parse(markup)
      @filters = []
-      return unless markup =~ MarkupWithQuotedFragment
+      return unless markup =~ /(#{QuotedFragment})(.*)/om

      name_markup = $1
      filter_markup = $2
      @name = Expression.parse(name_markup)
-      if filter_markup =~ FilterMarkupRegex
+      if filter_markup =~ /#{FilterSeparator}\s*(.*)/om
        filters = $1.scan(FilterParser)
        filters.each do |f|
          next unless f =~ /\w+/
          filtername = Regexp.last_match(0)
-          filterargs = f.scan(FilterArgsRegex).flatten
+          filterargs = f.scan(/(?:#{FilterArgumentSeparator}|#{ArgumentSeparator})\s*((?:\w+\s*\:\s*)?#{QuotedFragment})/o).flatten
          @filters << parse_filter_expressions(filtername, filterargs)
        end
      end
@@ -85,38 +79,26 @@ module Liquid
      end

      obj = context.apply_global_filter(obj)
+
      taint_check(context, obj)
+
      obj
    end

-    def render_to_output_buffer(context, output)
-      obj = render(context)
-
-      if obj.is_a?(Array)
-        output << obj.join
-      elsif obj.nil?
-      else
-        output << obj.to_s
-      end
-
-      output
-    end
-
    private

    def parse_filter_expressions(filter_name, unparsed_args)
      filter_args = []
-      keyword_args = nil
+      keyword_args = {}
      unparsed_args.each do |a|
-        if matches = a.match(JustTagAttributes)
-          keyword_args ||= {}
+        if matches = a.match(/\A#{TagAttributes}\z/o)
          keyword_args[matches[1]] = Expression.parse(matches[2])
        else
          filter_args << Expression.parse(a)
        end
      end
      result = [filter_name, filter_args]
-      result << keyword_args if keyword_args
+      result << keyword_args unless keyword_args.empty?
      result
    end

@@ -150,11 +132,5 @@ module Liquid
        raise error
      end
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        [@node.name] + @node.filters.flatten
-      end
-    end
  end
 end
--- a/lib/liquid/variable_lookup.rb
+++ b/lib/liquid/variable_lookup.rb
@@ -1,7 +1,7 @@
 module Liquid
  class VariableLookup
    SQUARE_BRACKETED = /\A\[(.*)\]\z/m
-    COMMAND_METHODS = ['size'.freeze, 'first'.freeze, 'last'.freeze].freeze
+    COMMAND_METHODS = ['size'.freeze, 'first'.freeze, 'last'.freeze]

    attr_reader :name, :lookups

@@ -78,11 +78,5 @@ module Liquid
    def state
      [@name, @lookups, @command_flags]
    end
-
-    class ParseTreeVisitor < Liquid::ParseTreeVisitor
-      def children
-        @node.lookups
-      end
-    end
  end
 end
--- a/lib/liquid/version.rb
+++ b/lib/liquid/version.rb
@@ -1,5 +1,4 @@
 # encoding: utf-8
-
 module Liquid
-  VERSION = "4.0.3".freeze
+  VERSION = "4.0.0"
 end
--- a/liquid.gemspec
+++ b/liquid.gemspec
@@ -1,5 +1,4 @@
 # encoding: utf-8
-
 lib = File.expand_path('../lib/', __FILE__)
 $LOAD_PATH.unshift lib unless $LOAD_PATH.include?(lib)

--- a/performance/memory_profile.rb
+++ b/performance/memory_profile.rb
@@ -1,62 +0,0 @@
-# frozen_string_literal: true
-
-require 'benchmark/ips'
-require 'memory_profiler'
-require 'terminal-table'
-require_relative 'theme_runner'
-
-class Profiler
-  LOG_LABEL   = "Profiling: ".rjust(14).freeze
-  REPORTS_DIR = File.expand_path('.memprof', __dir__).freeze
-
-  def self.run
-    puts
-    yield new
-  end
-
-  def initialize
-    @allocated = []
-    @retained  = []
-    @headings  = []
-  end
-
-  def profile(phase, &block)
-    print LOG_LABEL
-    print "#{phase}.. ".ljust(10)
-    report = MemoryProfiler.report(&block)
-    puts 'Done.'
-    @headings  << phase.capitalize
-    @allocated << "#{report.scale_bytes(report.total_allocated_memsize)} (#{report.total_allocated} objects)"
-    @retained  << "#{report.scale_bytes(report.total_retained_memsize)} (#{report.total_retained} objects)"
-
-    return if ENV['CI']
-    require 'fileutils'
-    report_file = File.join(REPORTS_DIR, "#{sanitize(phase)}.txt")
-    FileUtils.mkdir_p(REPORTS_DIR)
-    report.pretty_print(to_file: report_file, scale_bytes: true)
-  end
-
-  def tabulate
-    table = Terminal::Table.new(headings: @headings.unshift('Phase')) do |t|
-      t << @allocated.unshift('Total allocated')
-      t << @retained.unshift('Total retained')
-    end
-
-    puts
-    puts table
-    puts "\nDetailed report(s) saved to #{REPORTS_DIR}/" unless ENV['CI']
-  end
-
-  def sanitize(string)
-    string.downcase.gsub(/[\W]/, '-').squeeze('-')
-  end
-end
-
-Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
-
-runner = ThemeRunner.new
-Profiler.run do |x|
-  x.profile('parse') { runner.compile }
-  x.profile('render') { runner.render }
-  x.tabulate
-end
--- a/performance/shopify/comment_form.rb
+++ b/performance/shopify/comment_form.rb
@@ -12,7 +12,7 @@ class CommentForm < Liquid::Block
    end
  end

-  def render_to_output_buffer(context, output)
+  def render(context)
    article = context[@variable_name]

    context.stack do
@@ -23,9 +23,7 @@ class CommentForm < Liquid::Block
        'email'  => context['comment.email'],
        'body'   => context['comment.body']
      }
-
-      output << wrap_in_form(article, render_all(@nodelist, context, output))
-      output
+      wrap_in_form(article, render_all(@nodelist, context))
    end
  end

--- a/performance/shopify/paginate.rb
+++ b/performance/shopify/paginate.rb
@@ -21,7 +21,7 @@ class Paginate < Liquid::Block
    end
  end

-  def render_to_output_buffer(context, output)
+  def render(context)
    @context = context

    context.stack do
--- a/test/integration/blank_test.rb
+++ b/test/integration/blank_test.rb
@@ -1,10 +1,11 @@
 require 'test_helper'

 class FoobarTag < Liquid::Tag
-  def render_to_output_buffer(context, output)
-    output << ' '
-    output
+  def render(*args)
+    " "
  end
+
+  Liquid::Template.register_tag('foobar', FoobarTag)
 end

 class BlankTestFileSystem
@@ -30,9 +31,7 @@ class BlankTest < Minitest::Test
  end

  def test_new_tags_are_not_blank_by_default
-    with_custom_tag('foobar', FoobarTag) do
-      assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
-    end
+    assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
  end

  def test_loops_are_blank
--- a/test/integration/block_test.rb
+++ b/test/integration/block_test.rb
@@ -1,12 +0,0 @@
-require 'test_helper'
-
-class BlockTest < Minitest::Test
-  include Liquid
-
-  def test_unexpected_end_tag
-    exc = assert_raises(SyntaxError) do
-      Template.parse("{% if true %}{% endunless %}")
-    end
-    assert_equal exc.message, "Liquid syntax error: 'endunless' is not a valid delimiter for if tags. use endif"
-  end
-end
--- a/test/integration/error_handling_test.rb
+++ b/test/integration/error_handling_test.rb
@@ -123,7 +123,7 @@ class ErrorHandlingTest < Minitest::Test
            ',
      error_mode: :warn,
      line_numbers: true
-    )
+                                     )

    assert_equal ['Liquid syntax error (line 4): Unexpected character = in "1 =! 2"'],
      template.warnings.map(&:message)
@@ -140,7 +140,7 @@ class ErrorHandlingTest < Minitest::Test
                ',
        error_mode: :strict,
        line_numbers: true
-      )
+                            )
    end

    assert_equal 'Liquid syntax error (line 4): Unexpected character = in "1 =! 2"', err.message
@@ -158,7 +158,7 @@ class ErrorHandlingTest < Minitest::Test
          bla
                ',
        line_numbers: true
-      )
+                            )
    end

    assert_equal "Liquid syntax error (line 5): Unknown tag 'foo'", err.message
--- a/test/integration/parse_tree_visitor_test.rb
+++ b/test/integration/parse_tree_visitor_test.rb
@@ -1,247 +0,0 @@
-# frozen_string_literal: true
-
-require 'test_helper'
-
-class ParseTreeVisitorTest < Minitest::Test
-  include Liquid
-
-  def test_variable
-    assert_equal(
-      ["test"],
-      visit(%({{ test }}))
-    )
-  end
-
-  def test_varible_with_filter
-    assert_equal(
-      ["test", "infilter"],
-      visit(%({{ test | split: infilter }}))
-    )
-  end
-
-  def test_dynamic_variable
-    assert_equal(
-      ["test", "inlookup"],
-      visit(%({{ test[inlookup] }}))
-    )
-  end
-
-  def test_if_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if test %}{% endif %}))
-    )
-  end
-
-  def test_complex_if_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 and 2 == test %}{% endif %}))
-    )
-  end
-
-  def test_if_body
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{{ test }}{% endif %}))
-    )
-  end
-
-  def test_unless_condition
-    assert_equal(
-      ["test"],
-      visit(%({% unless test %}{% endunless %}))
-    )
-  end
-
-  def test_complex_unless_condition
-    assert_equal(
-      ["test"],
-      visit(%({% unless 1 == 1 and 2 == test %}{% endunless %}))
-    )
-  end
-
-  def test_unless_body
-    assert_equal(
-      ["test"],
-      visit(%({% unless 1 == 1 %}{{ test }}{% endunless %}))
-    )
-  end
-
-  def test_elsif_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% elsif test %}{% endif %}))
-    )
-  end
-
-  def test_complex_elsif_condition
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% elsif 1 == 1 and 2 == test %}{% endif %}))
-    )
-  end
-
-  def test_elsif_body
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% elsif 2 == 2 %}{{ test }}{% endif %}))
-    )
-  end
-
-  def test_else_body
-    assert_equal(
-      ["test"],
-      visit(%({% if 1 == 1 %}{% else %}{{ test }}{% endif %}))
-    )
-  end
-
-  def test_case_left
-    assert_equal(
-      ["test"],
-      visit(%({% case test %}{% endcase %}))
-    )
-  end
-
-  def test_case_condition
-    assert_equal(
-      ["test"],
-      visit(%({% case 1 %}{% when test %}{% endcase %}))
-    )
-  end
-
-  def test_case_when_body
-    assert_equal(
-      ["test"],
-      visit(%({% case 1 %}{% when 2 %}{{ test }}{% endcase %}))
-    )
-  end
-
-  def test_case_else_body
-    assert_equal(
-      ["test"],
-      visit(%({% case 1 %}{% else %}{{ test }}{% endcase %}))
-    )
-  end
-
-  def test_for_in
-    assert_equal(
-      ["test"],
-      visit(%({% for x in test %}{% endfor %}))
-    )
-  end
-
-  def test_for_limit
-    assert_equal(
-      ["test"],
-      visit(%({% for x in (1..5) limit: test %}{% endfor %}))
-    )
-  end
-
-  def test_for_offset
-    assert_equal(
-      ["test"],
-      visit(%({% for x in (1..5) offset: test %}{% endfor %}))
-    )
-  end
-
-  def test_for_body
-    assert_equal(
-      ["test"],
-      visit(%({% for x in (1..5) %}{{ test }}{% endfor %}))
-    )
-  end
-
-  def test_tablerow_in
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in test %}{% endtablerow %}))
-    )
-  end
-
-  def test_tablerow_limit
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in (1..5) limit: test %}{% endtablerow %}))
-    )
-  end
-
-  def test_tablerow_offset
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in (1..5) offset: test %}{% endtablerow %}))
-    )
-  end
-
-  def test_tablerow_body
-    assert_equal(
-      ["test"],
-      visit(%({% tablerow x in (1..5) %}{{ test }}{% endtablerow %}))
-    )
-  end
-
-  def test_cycle
-    assert_equal(
-      ["test"],
-      visit(%({% cycle test %}))
-    )
-  end
-
-  def test_assign
-    assert_equal(
-      ["test"],
-      visit(%({% assign x = test %}))
-    )
-  end
-
-  def test_capture
-    assert_equal(
-      ["test"],
-      visit(%({% capture x %}{{ test }}{% endcapture %}))
-    )
-  end
-
-  def test_include
-    assert_equal(
-      ["test"],
-      visit(%({% include test %}))
-    )
-  end
-
-  def test_include_with
-    assert_equal(
-      ["test"],
-      visit(%({% include "hai" with test %}))
-    )
-  end
-
-  def test_include_for
-    assert_equal(
-      ["test"],
-      visit(%({% include "hai" for test %}))
-    )
-  end
-
-  def test_preserve_tree_structure
-    assert_equal(
-      [[nil, [
-        [nil, [[nil, [["other", []]]]]],
-        ["test", []],
-        ["xs", []]
-      ]]],
-      traversal(%({% for x in xs offset: test %}{{ other }}{% endfor %})).visit
-    )
-  end
-
-  private
-
-  def traversal(template)
-    ParseTreeVisitor
-      .for(Template.parse(template).root)
-      .add_callback_for(VariableLookup, &:name)
-  end
-
-  def visit(template)
-    traversal(template).visit.flatten.compact
-  end
-end
--- a/test/integration/parsing_quirks_test.rb
+++ b/test/integration/parsing_quirks_test.rb
@@ -99,7 +99,7 @@ class ParsingQuirksTest < Minitest::Test
      # After the messed up quotes a filter without parameters (reverse) should work
      # but one with parameters (remove) shouldn't be detected.
      assert_template_result('here',  "{{ 'hi there' | split:\"t\"\" | reverse | first}}")
-      assert_template_result('hi ', "{{ 'hi there' | split:\"t\"\" | remove:\"i\" | first}}")
+      assert_template_result('hi ',  "{{ 'hi there' | split:\"t\"\" | remove:\"i\" | first}}")
    end
  end

--- a/test/integration/standard_filter_test.rb
+++ b/test/integration/standard_filter_test.rb
@@ -158,10 +158,6 @@ class StandardFiltersTest < Minitest::Test
    assert_equal '1', @filters.url_decode(1)
    assert_equal '2001-02-03', @filters.url_decode(Date.new(2001, 2, 3))
    assert_nil @filters.url_decode(nil)
-    exception = assert_raises Liquid::ArgumentError do
-      @filters.url_decode('%ff')
-    end
-    assert_equal 'Liquid error: invalid byte sequence in UTF-8', exception.message
  end

  def test_truncatewords
@@ -181,9 +177,6 @@ class StandardFiltersTest < Minitest::Test
    assert_equal 'test', @filters.strip_html("<div\nclass='multiline'>test</div>")
    assert_equal 'test', @filters.strip_html("<!-- foo bar \n test -->test")
    assert_equal '', @filters.strip_html(nil)
-
-    # Quirk of the existing implementation
-    assert_equal 'foo;', @filters.strip_html("<<<script </script>script>foo;</script>")
  end

  def test_join
@@ -197,11 +190,6 @@ class StandardFiltersTest < Minitest::Test
    assert_equal [{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }], @filters.sort([{ "a" => 4 }, { "a" => 3 }, { "a" => 1 }, { "a" => 2 }], "a")
  end

-  def test_sort_with_nils
-    assert_equal [1, 2, 3, 4, nil], @filters.sort([nil, 4, 3, 2, 1])
-    assert_equal [{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }, {}], @filters.sort([{ "a" => 4 }, { "a" => 3 }, {}, { "a" => 1 }, { "a" => 2 }], "a")
-  end
-
  def test_sort_when_property_is_sometimes_missing_puts_nils_last
    input = [
      { "price" => 4, "handle" => "alpha" },
@@ -220,89 +208,14 @@ class StandardFiltersTest < Minitest::Test
    assert_equal expectation, @filters.sort(input, "price")
  end

-  def test_sort_natural
-    assert_equal ["a", "B", "c", "D"], @filters.sort_natural(["c", "D", "a", "B"])
-    assert_equal [{ "a" => "a" }, { "a" => "B" }, { "a" => "c" }, { "a" => "D" }], @filters.sort_natural([{ "a" => "D" }, { "a" => "c" }, { "a" => "a" }, { "a" => "B" }], "a")
-  end
-
-  def test_sort_natural_with_nils
-    assert_equal ["a", "B", "c", "D", nil], @filters.sort_natural([nil, "c", "D", "a", "B"])
-    assert_equal [{ "a" => "a" }, { "a" => "B" }, { "a" => "c" }, { "a" => "D" }, {}], @filters.sort_natural([{ "a" => "D" }, { "a" => "c" }, {}, { "a" => "a" }, { "a" => "B" }], "a")
-  end
-
-  def test_sort_natural_when_property_is_sometimes_missing_puts_nils_last
-    input = [
-      { "price" => "4", "handle" => "alpha" },
-      { "handle" => "beta" },
-      { "price" => "1", "handle" => "gamma" },
-      { "handle" => "delta" },
-      { "price" => 2, "handle" => "epsilon" }
-    ]
-    expectation = [
-      { "price" => "1", "handle" => "gamma" },
-      { "price" => 2, "handle" => "epsilon" },
-      { "price" => "4", "handle" => "alpha" },
-      { "handle" => "delta" },
-      { "handle" => "beta" }
-    ]
-    assert_equal expectation, @filters.sort_natural(input, "price")
-  end
-
-  def test_sort_natural_case_check
-    input = [
-      { "key" => "X" },
-      { "key" => "Y" },
-      { "key" => "Z" },
-      { "fake" => "t" },
-      { "key" => "a" },
-      { "key" => "b" },
-      { "key" => "c" }
-    ]
-    expectation = [
-      { "key" => "a" },
-      { "key" => "b" },
-      { "key" => "c" },
-      { "key" => "X" },
-      { "key" => "Y" },
-      { "key" => "Z" },
-      { "fake" => "t" }
-    ]
-    assert_equal expectation, @filters.sort_natural(input, "key")
-    assert_equal ["a", "b", "c", "X", "Y", "Z"], @filters.sort_natural(["X", "Y", "Z", "a", "b", "c"])
-  end
-
  def test_sort_empty_array
    assert_equal [], @filters.sort([], "a")
  end

-  def test_sort_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.sort(foo, "bar")
-    end
-  end
-
  def test_sort_natural_empty_array
    assert_equal [], @filters.sort_natural([], "a")
  end

-  def test_sort_natural_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.sort_natural(foo, "bar")
-    end
-  end
-
  def test_legacy_sort_hash
    assert_equal [{ a: 1, b: 2 }], @filters.sort({ a: 1, b: 2 })
  end
@@ -326,34 +239,10 @@ class StandardFiltersTest < Minitest::Test
    assert_equal [], @filters.uniq([], "a")
  end

-  def test_uniq_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.uniq(foo, "bar")
-    end
-  end
-
  def test_compact_empty_array
    assert_equal [], @filters.compact([], "a")
  end

-  def test_compact_invalid_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.compact(foo, "bar")
-    end
-  end
-
  def test_reverse
    assert_equal [4, 3, 2, 1], @filters.reverse([1, 2, 3, 4])
  end
@@ -419,29 +308,6 @@ class StandardFiltersTest < Minitest::Test
    assert_template_result "123", '{{ foo | map: "foo" }}', "foo" => TestEnumerable.new
  end

-  def test_map_returns_empty_on_2d_input_array
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-
-    assert_raises Liquid::ArgumentError do
-      @filters.map(foo, "bar")
-    end
-  end
-
-  def test_map_returns_empty_with_no_property
-    foo = [
-      [1],
-      [2],
-      [3]
-    ]
-    assert_raises Liquid::ArgumentError do
-      @filters.map(foo, nil)
-    end
-  end
-
  def test_sort_works_on_enumerables
    assert_template_result "213", '{{ foo | sort: "bar" | map: "foo" }}', "foo" => TestEnumerable.new
  end
@@ -472,9 +338,9 @@ class StandardFiltersTest < Minitest::Test
    assert_equal '07/05/2006', @filters.date("2006-07-05 10:00:00", "%m/%d/%Y")

    assert_equal "07/16/2004", @filters.date("Fri Jul 16 01:00:00 2004", "%m/%d/%Y")
-    assert_equal Date.today.year.to_s, @filters.date('now', '%Y')
-    assert_equal Date.today.year.to_s, @filters.date('today', '%Y')
-    assert_equal Date.today.year.to_s, @filters.date('Today', '%Y')
+    assert_equal "#{Date.today.year}", @filters.date('now', '%Y')
+    assert_equal "#{Date.today.year}", @filters.date('today', '%Y')
+    assert_equal "#{Date.today.year}", @filters.date('Today', '%Y')

    assert_nil @filters.date(nil, "%B")

@@ -496,8 +362,10 @@ class StandardFiltersTest < Minitest::Test
  def test_replace
    assert_equal '2 2 2 2', @filters.replace('1 1 1 1', '1', 2)
    assert_equal '2 2 2 2', @filters.replace('1 1 1 1', 1, 2)
+    assert_equal "\\& \\& \\& \\&", @filters.replace('1 1 1 1', '1', "\\&")
    assert_equal '2 1 1 1', @filters.replace_first('1 1 1 1', '1', 2)
    assert_equal '2 1 1 1', @filters.replace_first('1 1 1 1', 1, 2)
+    assert_equal '\\& 1 1 1', @filters.replace_first("1 1 1 1", '1', "\\&")
    assert_template_result '2 1 1 1', "{{ '1 1 1 1' | replace_first: '1', 2 }}"
  end

@@ -630,28 +498,6 @@ class StandardFiltersTest < Minitest::Test
    assert_template_result "5", "{{ price | floor }}", 'price' => NumberLikeThing.new(5.4)
  end

-  def test_at_most
-    assert_template_result "4", "{{ 5 | at_most:4 }}"
-    assert_template_result "5", "{{ 5 | at_most:5 }}"
-    assert_template_result "5", "{{ 5 | at_most:6 }}"
-
-    assert_template_result "4.5", "{{ 4.5 | at_most:5 }}"
-    assert_template_result "5", "{{ width | at_most:5 }}", 'width' => NumberLikeThing.new(6)
-    assert_template_result "4", "{{ width | at_most:5 }}", 'width' => NumberLikeThing.new(4)
-    assert_template_result "4", "{{ 5 | at_most: width }}", 'width' => NumberLikeThing.new(4)
-  end
-
-  def test_at_least
-    assert_template_result "5", "{{ 5 | at_least:4 }}"
-    assert_template_result "5", "{{ 5 | at_least:5 }}"
-    assert_template_result "6", "{{ 5 | at_least:6 }}"
-
-    assert_template_result "5", "{{ 4.5 | at_least:5 }}"
-    assert_template_result "6", "{{ width | at_least:5 }}", 'width' => NumberLikeThing.new(6)
-    assert_template_result "5", "{{ width | at_least:5 }}", 'width' => NumberLikeThing.new(4)
-    assert_template_result "6", "{{ 5 | at_least: width }}", 'width' => NumberLikeThing.new(6)
-  end
-
  def test_append
    assigns = { 'a' => 'bc', 'b' => 'd' }
    assert_template_result('bcd', "{{ a | append: 'd'}}", assigns)
@@ -692,78 +538,6 @@ class StandardFiltersTest < Minitest::Test
    assert_template_result('abc', "{{ 'abc' | date: '%D' }}")
  end

-  def test_where
-    input = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "beta", "ok" => false },
-      { "handle" => "gamma", "ok" => false },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    expectation = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    assert_equal expectation, @filters.where(input, "ok", true)
-    assert_equal expectation, @filters.where(input, "ok")
-  end
-
-  def test_where_no_key_set
-    input = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "beta" },
-      { "handle" => "gamma" },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    expectation = [
-      { "handle" => "alpha", "ok" => true },
-      { "handle" => "delta", "ok" => true }
-    ]
-
-    assert_equal expectation, @filters.where(input, "ok", true)
-    assert_equal expectation, @filters.where(input, "ok")
-  end
-
-  def test_where_non_array_map_input
-    assert_equal [{ "a" => "ok" }], @filters.where({ "a" => "ok" }, "a", "ok")
-    assert_equal [], @filters.where({ "a" => "not ok" }, "a", "ok")
-  end
-
-  def test_where_indexable_but_non_map_value
-    assert_raises(Liquid::ArgumentError) { @filters.where(1, "ok", true) }
-    assert_raises(Liquid::ArgumentError) { @filters.where(1, "ok") }
-  end
-
-  def test_where_non_boolean_value
-    input = [
-      { "message" => "Bonjour!", "language" => "French" },
-      { "message" => "Hello!", "language" => "English" },
-      { "message" => "Hallo!", "language" => "German" }
-    ]
-
-    assert_equal [{ "message" => "Bonjour!", "language" => "French" }], @filters.where(input, "language", "French")
-    assert_equal [{ "message" => "Hallo!", "language" => "German" }], @filters.where(input, "language", "German")
-    assert_equal [{ "message" => "Hello!", "language" => "English" }], @filters.where(input, "language", "English")
-  end
-
-  def test_where_array_of_only_unindexable_values
-    assert_nil @filters.where([nil], "ok", true)
-    assert_nil @filters.where([nil], "ok")
-  end
-
-  def test_where_no_target_value
-    input = [
-      { "foo" => false },
-      { "foo" => true },
-      { "foo" => "for sure" },
-      { "bar" => true }
-    ]
-
-    assert_equal [{ "foo" => true }, { "foo" => "for sure" }], @filters.where(input, "foo")
-  end
-
  private

  def with_timezone(tz)
--- a/test/integration/tags/echo_test.rb
+++ b/test/integration/tags/echo_test.rb
@@ -1,11 +0,0 @@
-require 'test_helper'
-
-class EchoTest < Minitest::Test
-  include Liquid
-
-  def test_echo_outputs_its_input
-    assert_template_result('BAR', <<~LIQUID, { 'variable-name' => 'bar' })
-      {%- echo variable-name | upcase -%}
-    LIQUID
-  end
-end
--- a/test/integration/tags/for_tag_test.rb
+++ b/test/integration/tags/for_tag_test.rb
@@ -103,34 +103,6 @@ HERE
    assert_template_result('3456', '{%for i in array limit: 4 offset: 2 %}{{ i }}{%endfor%}', assigns)
  end

-  def test_limiting_with_invalid_limit
-    assigns = { 'array' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] }
-    template = <<-MKUP
-      {% for i in array limit: true offset: 1 %}
-        {{ i }}
-      {% endfor %}
-    MKUP
-
-    exception = assert_raises(Liquid::ArgumentError) do
-      Template.parse(template).render!(assigns)
-    end
-    assert_equal("Liquid error: invalid integer", exception.message)
-  end
-
-  def test_limiting_with_invalid_offset
-    assigns = { 'array' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] }
-    template = <<-MKUP
-      {% for i in array limit: 1 offset: true %}
-        {{ i }}
-      {% endfor %}
-    MKUP
-
-    exception = assert_raises(Liquid::ArgumentError) do
-      Template.parse(template).render!(assigns)
-    end
-    assert_equal("Liquid error: invalid integer", exception.message)
-  end
-
  def test_dynamic_variable_limiting
    assigns = { 'array' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] }
    assigns['limit'] = 2
@@ -187,7 +159,7 @@ HERE
    assert_template_result(expected, markup, assigns)
  end

-  def test_pause_resume_big_limit
+  def test_pause_resume_BIG_limit
    assigns = { 'array' => { 'items' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] } }
    markup = <<-MKUP
      {%for i in array.items limit:3 %}{{i}}{%endfor%}
@@ -206,7 +178,7 @@ HERE
    assert_template_result(expected, markup, assigns)
  end

-  def test_pause_resume_big_offset
+  def test_pause_resume_BIG_offset
    assigns = { 'array' => { 'items' => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] } }
    markup = '{%for i in array.items limit:3 %}{{i}}{%endfor%}
      next
--- a/test/integration/tags/include_tag_test.rb
+++ b/test/integration/tags/include_tag_test.rb
@@ -30,9 +30,6 @@ class TestFileSystem
    when 'assignments'
      "{% assign foo = 'bar' %}"

-    when 'break'
-      "{% break %}"
-
    else
      template_path
    end
@@ -66,9 +63,8 @@ class CustomInclude < Liquid::Tag
  def parse(tokens)
  end

-  def render_to_output_buffer(context, output)
-    output << @template_name[1..-2]
-    output
+  def render(context)
+    @template_name[1..-2]
  end
 end

@@ -246,9 +242,4 @@ class IncludeTagTest < Minitest::Test

    assert_equal [], template.errors
  end
-
-  def test_break_through_include
-    assert_template_result "1", "{% for i in (1..3) %}{{ i }}{% break %}{{ i }}{% endfor %}"
-    assert_template_result "1", "{% for i in (1..3) %}{{ i }}{% include 'break' %}{{ i }}{% endfor %}"
-  end
 end # IncludeTagTest
--- a/test/integration/tags/liquid_tag_test.rb
+++ b/test/integration/tags/liquid_tag_test.rb
@@ -1,104 +0,0 @@
-require 'test_helper'
-
-class LiquidTagTest < Minitest::Test
-  include Liquid
-
-  def test_liquid_tag
-    assert_template_result('1 2 3', <<~LIQUID, 'array' => [1, 2, 3])
-    {%- liquid
-      echo array | join: " "
-    -%}
-    LIQUID
-
-    assert_template_result('1 2 3', <<~LIQUID, 'array' => [1, 2, 3])
-    {%- liquid
-      for value in array
-        echo value
-        unless forloop.last
-          echo " "
-        endunless
-      endfor
-    -%}
-    LIQUID
-
-    assert_template_result('4 8 12 6', <<~LIQUID, 'array' => [1, 2, 3])
-    {%- liquid
-      for value in array
-        assign double_value = value | times: 2
-        echo double_value | times: 2
-        unless forloop.last
-          echo " "
-        endunless
-      endfor
-
-      echo " "
-      echo double_value
-    -%}
-    LIQUID
-
-    assert_template_result('abc', <<~LIQUID)
-    {%- liquid echo "a" -%}
-    b
-    {%- liquid echo "c" -%}
-    LIQUID
-  end
-
-  def test_liquid_tag_errors
-    assert_match_syntax_error("syntax error (line 1): Unknown tag 'error'", <<~LIQUID)
-    {%- liquid error no such tag -%}
-    LIQUID
-
-    assert_match_syntax_error("syntax error (line 7): Unknown tag 'error'", <<~LIQUID)
-    {{ test }}
-
-    {%-
-    liquid
-      for value in array
-
-        error no such tag
-      endfor
-    -%}
-    LIQUID
-
-    assert_match_syntax_error("syntax error (line 2): Unknown tag '!!! the guards are vigilant'", <<~LIQUID)
-    {%- liquid
-      !!! the guards are vigilant
-    -%}
-    LIQUID
-
-    assert_match_syntax_error("syntax error (line 4): 'for' tag was never closed", <<~LIQUID)
-    {%- liquid
-      for value in array
-        echo 'forgot to close the for tag'
-    -%}
-    LIQUID
-  end
-
-  def test_line_number_is_correct_after_a_blank_token
-    assert_match_syntax_error("syntax error (line 3): Unknown tag 'error'", "{% liquid echo ''\n\n error %}")
-    assert_match_syntax_error("syntax error (line 3): Unknown tag 'error'", "{% liquid echo ''\n  \n error %}")
-  end
-
-  def test_cannot_open_blocks_living_past_a_liquid_tag
-    assert_match_syntax_error("syntax error (line 3): 'if' tag was never closed", <<~LIQUID)
-    {%- liquid
-      if true
-    -%}
-    {%- endif -%}
-    LIQUID
-  end
-
-  def test_quirk_can_close_blocks_created_before_a_liquid_tag
-    assert_template_result("42", <<~LIQUID)
-    {%- if true -%}
-    42
-    {%- liquid endif -%}
-    LIQUID
-  end
-
-  def test_liquid_tag_in_raw
-    assert_template_result("{% liquid echo 'test' %}\n", <<~LIQUID)
-    {% raw %}{% liquid echo 'test' %}{% endraw %}
-    LIQUID
-  end
-end
--- a/test/integration/template_test.rb
+++ b/test/integration/template_test.rb
@@ -139,16 +139,6 @@ class TemplateTest < Minitest::Test
    refute_nil t.resource_limits.assign_score
  end

-  def test_resource_limits_assign_score_counts_bytes_not_characters
-    t = Template.parse("{% assign foo = 'すごい' %}")
-    t.render
-    assert_equal 9, t.resource_limits.assign_score
-
-    t = Template.parse("{% capture foo %}すごい{% endcapture %}")
-    t.render
-    assert_equal 9, t.resource_limits.assign_score
-  end
-
  def test_resource_limits_assign_score_nested
    t = Template.parse("{% assign foo = 'aaaa' | reverse %}")

@@ -197,14 +187,6 @@ class TemplateTest < Minitest::Test
    assert_equal "ababab", t.render
  end

-  def test_render_length_uses_number_of_bytes_not_characters
-    t = Template.parse("{% if true %}すごい{% endif %}")
-    t.resource_limits.render_length_limit = 10
-    assert_equal "Liquid error: Memory limits exceeded", t.render
-    t.resource_limits.render_length_limit = 18
-    assert_equal "すごい", t.render
-  end
-
  def test_default_resource_limits_unaffected_by_render_with_context
    context = Context.new
    t = Template.parse("{% for a in (1..100) %} {% assign foo = 1 %} {% endfor %}")
--- a/test/integration/trim_mode_test.rb
+++ b/test/integration/trim_mode_test.rb
@@ -496,10 +496,6 @@ class TrimModeTest < Minitest::Test
    assert_template_result(expected, text)
  end

-  def test_right_trim_followed_by_tag
-    assert_template_result('ab c', '{{ "a" -}}{{ "b" }} c')
-  end
-
  def test_raw_output
    whitespace = '        '
    text = <<-END_TEMPLATE
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -37,18 +37,18 @@ module Minitest
    include Liquid

    def assert_template_result(expected, template, assigns = {}, message = nil)
-      assert_equal expected, Template.parse(template, line_numbers: true).render!(assigns), message
+      assert_equal expected, Template.parse(template).render!(assigns), message
    end

    def assert_template_result_matches(expected, template, assigns = {}, message = nil)
      return assert_template_result(expected, template, assigns, message) unless expected.is_a? Regexp

-      assert_match expected, Template.parse(template, line_numbers: true).render!(assigns), message
+      assert_match expected, Template.parse(template).render!(assigns), message
    end

    def assert_match_syntax_error(match, template, assigns = {})
      exception = assert_raises(Liquid::SyntaxError) do
-        Template.parse(template, line_numbers: true).render(assigns)
+        Template.parse(template).render(assigns)
      end
      assert_match match, exception.message
    end
@@ -84,13 +84,6 @@ module Minitest
    ensure
      Liquid::Template.error_mode = old_mode
    end
-
-    def with_custom_tag(tag_name, tag_class)
-      Liquid::Template.register_tag(tag_name, tag_class)
-      yield
-    ensure
-      Liquid::Template.tags.delete(tag_name)
-    end
  end
 end

--- a/test/unit/block_unit_test.rb
+++ b/test/unit/block_unit_test.rb
@@ -44,47 +44,10 @@ class BlockUnitTest < Minitest::Test
  end

  def test_with_custom_tag
-    with_custom_tag('testtag', Block) do
-      assert Liquid::Template.parse("{% testtag %} {% endtesttag %}")
-    end
-  end
-
-  def test_custom_block_tags_have_a_default_render_to_output_buffer_method_for_backwards_compatibility
-    klass1 = Class.new(Block) do
-      def render(*)
-        'hello'
-      end
-    end
-
-    with_custom_tag('blabla', klass1) do
-      template = Liquid::Template.parse("{% blabla %} bla {% endblabla %}")
-
-      assert_equal 'hello', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'hello', output
-      assert_equal 'hello', buf
-      assert_equal buf.object_id, output.object_id
-    end
-
-    klass2 = Class.new(klass1) do
-      def render(*)
-        'foo' + super + 'bar'
-      end
-    end
-
-    with_custom_tag('blabla', klass2) do
-      template = Liquid::Template.parse("{% blabla %} foo {% endblabla %}")
-
-      assert_equal 'foohellobar', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'foohellobar', output
-      assert_equal 'foohellobar', buf
-      assert_equal buf.object_id, output.object_id
-    end
+    Liquid::Template.register_tag("testtag", Block)
+    assert Liquid::Template.parse("{% testtag %} {% endtesttag %}")
+  ensure
+    Liquid::Template.tags.delete('testtag')
  end

  private
--- a/test/unit/condition_unit_test.rb
+++ b/test/unit/condition_unit_test.rb
@@ -24,9 +24,9 @@ class ConditionUnitTest < Minitest::Test
    assert_evaluates_true 1, '<=', 1
    # negative numbers
    assert_evaluates_true 1, '>', -1
-    assert_evaluates_true -1, '<', 1
+    assert_evaluates_true (-1), '<', 1
    assert_evaluates_true 1.0, '>', -1.0
-    assert_evaluates_true -1.0, '<', 1.0
+    assert_evaluates_true (-1.0), '<', 1.0
  end

  def test_default_operators_evalute_false
--- a/test/unit/tag_unit_test.rb
+++ b/test/unit/tag_unit_test.rb
@@ -18,42 +18,4 @@ class TagUnitTest < Minitest::Test
    tag = Tag.parse("some_tag", "", Tokenizer.new(""), ParseContext.new)
    assert_equal 'some_tag', tag.tag_name
  end
-
-  def test_custom_tags_have_a_default_render_to_output_buffer_method_for_backwards_compatibility
-    klass1 = Class.new(Tag) do
-      def render(*)
-        'hello'
-      end
-    end
-
-    with_custom_tag('blabla', klass1) do
-      template = Liquid::Template.parse("{% blabla %}")
-
-      assert_equal 'hello', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'hello', output
-      assert_equal 'hello', buf
-      assert_equal buf.object_id, output.object_id
-    end
-
-    klass2 = Class.new(klass1) do
-      def render(*)
-        'foo' + super + 'bar'
-      end
-    end
-
-    with_custom_tag('blabla', klass2) do
-      template = Liquid::Template.parse("{% blabla %}")
-
-      assert_equal 'foohellobar', template.render
-
-      buf = ''
-      output = template.render({}, output: buf)
-      assert_equal 'foohellobar', output
-      assert_equal 'foohellobar', buf
-      assert_equal buf.object_id, output.object_id
-    end
-  end
 end