Remove hasnling false scopes

Remove lazy load stacks and instead only create a new scope when a tag is known to need one

.rubocop.yml

@@ -2,9 +2,15 @@ inherit_from:
   - .rubocop_todo.yml
   - ./.rubocop_todo.yml
 
+require: rubocop-performance
+
+Performance:
+  Enabled: true
+
 AllCops:
   Exclude:
     - 'performance/shopify/*'
+    - 'vendor/bundle/**/*'
     - 'pkg/**'
 
 Metrics/BlockNesting:
@@ -79,9 +85,6 @@ Style/TrailingCommaInArrayLiteral:
 Style/TrailingCommaInHashLiteral:
   Enabled: false
 
-Layout/IndentHash:
-  EnforcedStyle: consistent
-
 Style/FormatString:
   Enabled: false
 
@@ -106,9 +109,6 @@ Style/RegexpLiteral:
 Style/SymbolLiteral:
   Enabled: false
 
-Performance/Count:
-  Enabled: false
-
 Naming/ConstantName:
   Enabled: false
 

.rubocop_todo.yml

@@ -1,6 +1,6 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2019-04-22 19:11:24 -0400 using RuboCop version 0.53.0.
+# on 2019-08-29 00:43:36 +1000 using RuboCop version 0.74.0.
 # 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
@@ -8,16 +8,67 @@
 
 # Offense count: 1
 # Cop supports --auto-correct.
-# Configuration parameters: Include, TreatCommentsAsGroupSeparators.
+# Configuration parameters: TreatCommentsAsGroupSeparators, Include.
 # Include: **/*.gemspec
 Gemspec/OrderedDependencies:
   Exclude:
     - 'liquid.gemspec'
 
+# Offense count: 1
+# Configuration parameters: Include.
+# Include: **/*.gemspec, 
+Gemspec/RequiredRubyVersion:
+  Exclude:
+    - 'liquid.gemspec'
+
+# Offense count: 124
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle, IndentationWidth.
+# SupportedStyles: with_first_argument, with_fixed_indentation
+Layout/AlignArguments:
+  Enabled: false
+
+# Offense count: 7
+# Cop supports --auto-correct.
+# Configuration parameters: AllowMultipleStyles, EnforcedHashRocketStyle, EnforcedColonStyle, EnforcedLastArgumentHashStyle.
+# SupportedHashRocketStyles: key, separator, table
+# SupportedColonStyles: key, separator, table
+# SupportedLastArgumentHashStyles: always_inspect, always_ignore, ignore_implicit, ignore_explicit
+Layout/AlignHash:
+  Exclude:
+    - 'lib/liquid/condition.rb'
+    - 'lib/liquid/expression.rb'
+    - 'test/unit/context_unit_test.rb'
+
+# Offense count: 6
+# Cop supports --auto-correct.
+Layout/ClosingHeredocIndentation:
+  Exclude:
+    - 'test/integration/tags/for_tag_test.rb'
+
+# Offense count: 27
+# Cop supports --auto-correct.
+Layout/EmptyLineAfterGuardClause:
+  Exclude:
+    - 'lib/liquid/block.rb'
+    - 'lib/liquid/block_body.rb'
+    - 'lib/liquid/context.rb'
+    - 'lib/liquid/drop.rb'
+    - 'lib/liquid/lexer.rb'
+    - 'lib/liquid/parser.rb'
+    - 'lib/liquid/standardfilters.rb'
+    - 'lib/liquid/strainer.rb'
+    - 'lib/liquid/tags/for.rb'
+    - 'lib/liquid/tags/if.rb'
+    - 'lib/liquid/tags/include.rb'
+    - 'lib/liquid/utils.rb'
+    - 'lib/liquid/variable.rb'
+    - 'lib/liquid/variable_lookup.rb'
+
 # Offense count: 5
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle.
-# SupportedStyles: auto_detection, squiggly, active_support, powerpack, unindent
+# SupportedStyles: squiggly, active_support, powerpack, unindent
 Layout/IndentHeredoc:
   Exclude:
     - 'test/integration/tags/for_tag_test.rb'
@@ -32,6 +83,13 @@ Layout/MultilineMethodCallBraceLayout:
     - 'test/integration/error_handling_test.rb'
     - 'test/unit/strainer_unit_test.rb'
 
+# Offense count: 1
+# Cop supports --auto-correct.
+# Configuration parameters: AllowForAlignment.
+Layout/SpaceAroundOperators:
+  Exclude:
+    - 'lib/liquid/condition.rb'
+
 # Offense count: 2
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle.
@@ -54,27 +112,25 @@ Metrics/AbcSize:
 Metrics/CyclomaticComplexity:
   Max: 13
 
-# Offense count: 112
-# Configuration parameters: CountComments.
+# Offense count: 118
+# Configuration parameters: CountComments, ExcludedMethods.
 Metrics/MethodLength:
   Max: 38
 
-# Offense count: 8
+# Offense count: 9
 Metrics/PerceivedComplexity:
   Max: 11
 
-# Offense count: 52
-# Configuration parameters: Blacklist.
-# Blacklist: END, (?-mix:EO[A-Z]{1})
-Naming/HeredocDelimiterNaming:
+# Offense count: 1
+# Cop supports --auto-correct.
+# Configuration parameters: PreferredName.
+Naming/RescuedExceptionsVariableName:
   Exclude:
-    - 'test/integration/assign_test.rb'
-    - 'test/integration/capture_test.rb'
-    - 'test/integration/trim_mode_test.rb'
+    - 'lib/liquid/context.rb'
 
-# Offense count: 23
+# Offense count: 20
 # Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
-# AllowedNames: io, id
+# AllowedNames: io, id, to, by, on, in, at, ip, db
 Naming/UncommunicativeMethodParamName:
   Exclude:
     - 'example/server/example_servlet.rb'
@@ -82,15 +138,23 @@ Naming/UncommunicativeMethodParamName:
     - '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
+# Offense count: 5
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: inline, group
+Style/AccessModifierDeclarations:
+  Exclude:
+    - 'lib/liquid/block_body.rb'
+    - 'lib/liquid/tag.rb'
+    - 'lib/liquid/tags/include.rb'
+    - 'test/unit/strainer_unit_test.rb'
+
+# Offense count: 10
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle.
 # SupportedStyles: prefer_alias, prefer_alias_method
@@ -117,15 +181,9 @@ Style/ConditionalAssignment:
     - '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
@@ -163,6 +221,13 @@ Style/FormatStringToken:
     - 'test/integration/filter_test.rb'
     - 'test/integration/hash_ordering_test.rb'
 
+# Offense count: 106
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: always, never
+Style/FrozenStringLiteralComment:
+  Enabled: false
+
 # Offense count: 14
 # Configuration parameters: MinBodyLength.
 Style/GuardClause:
@@ -180,6 +245,13 @@ Style/GuardClause:
     - 'lib/liquid/variable.rb'
     - 'test/unit/tokenizer_unit_test.rb'
 
+# Offense count: 53
+# Cop supports --auto-correct.
+# Configuration parameters: EnforcedStyle.
+# SupportedStyles: literals, strict
+Style/MutableConstant:
+  Enabled: false
+
 # Offense count: 1
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle, MinBodyLength.
@@ -188,9 +260,9 @@ Style/Next:
   Exclude:
     - 'lib/liquid/tags/for.rb'
 
-# Offense count: 4
+# Offense count: 13
 # Cop supports --auto-correct.
-# Configuration parameters: AutoCorrect, EnforcedStyle.
+# Configuration parameters: AutoCorrect, EnforcedStyle, IgnoredMethods.
 # SupportedStyles: predicate, comparison
 Style/NumericPredicate:
   Exclude:
@@ -199,6 +271,8 @@ Style/NumericPredicate:
     - 'lib/liquid/forloop_drop.rb'
     - 'lib/liquid/standardfilters.rb'
     - 'lib/liquid/tablerowloop_drop.rb'
+    - 'test/integration/standard_filter_test.rb'
+    - 'test/integration/template_test.rb'
 
 # Offense count: 14
 # Cop supports --auto-correct.
@@ -216,6 +290,16 @@ Style/RedundantSelf:
   Exclude:
     - 'lib/liquid/strainer.rb'
 
+# Offense count: 3
+# Cop supports --auto-correct.
+# Configuration parameters: ConvertCodeThatCanStartToReturnNil, Whitelist.
+# Whitelist: present?, blank?, presence, try, try!
+Style/SafeNavigation:
+  Exclude:
+    - 'lib/liquid/drop.rb'
+    - 'lib/liquid/strainer.rb'
+    - 'lib/liquid/tokenizer.rb'
+
 # Offense count: 9
 # Cop supports --auto-correct.
 # Configuration parameters: AllowAsExpressionSeparator.
@@ -253,8 +337,9 @@ Style/WhileUntilModifier:
   Exclude:
     - 'lib/liquid/tags/case.rb'
 
-# Offense count: 648
-# Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
+# Offense count: 665
+# Cop supports --auto-correct.
+# Configuration parameters: AutoCorrect, AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
 # URISchemes: http, https
 Metrics/LineLength:
   Max: 294

.travis.yml

@@ -1,20 +1,14 @@
 language: ruby
 
 rvm:
-  - 2.1
-  - 2.2
-  - 2.3
   - 2.4
   - 2.5
   - &latest_ruby 2.6
+  - 2.7
   - ruby-head
   - jruby-head
-#  - rbx-2
+  - truffleruby
 
-addons:
-  apt:
-    packages:
-    - libgmp3-dev
 
 matrix:
   include:
@@ -24,9 +18,9 @@ matrix:
   allow_failures:
     - rvm: ruby-head
     - rvm: jruby-head
+    - rvm: truffleruby
 
-install:
-  - bundle install
+cache: bundler
 
 script: bundle exec rake
 

Gemfile

@@ -10,15 +10,16 @@ group :benchmark, :test do
   gem 'memory_profiler'
   gem 'terminal-table'
 
-  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ } do
+  install_if -> { RUBY_PLATFORM !~ /mingw|mswin|java/ && RUBY_ENGINE != 'truffleruby' } do
     gem 'stackprof'
   end
 end
 
 group :test do
-  gem 'rubocop', '~> 0.53.0'
+  gem 'rubocop', '~> 0.74.0', require: false
+  gem 'rubocop-performance', require: false
 
-  platform :mri do
+  platform :mri, :truffleruby do
     gem 'liquid-c', github: 'Shopify/liquid-c', ref: 'liquid-tag'
   end
 end

Rakefile

@@ -19,8 +19,10 @@ task :warn_test do
 end
 
 task :rubocop do
-  require 'rubocop/rake_task'
-  RuboCop::RakeTask.new
+  if RUBY_ENGINE == 'ruby'
+    require 'rubocop/rake_task'
+    RuboCop::RakeTask.new
+  end
 end
 
 desc 'runs test suite with both strict and lax parsers'
@@ -32,8 +34,8 @@ task :test do
   Rake::Task['base_test'].reenable
   Rake::Task['base_test'].invoke
 
-  if RUBY_ENGINE == 'ruby'
-    ENV['LIQUID-C'] = '1'
+  if RUBY_ENGINE == 'ruby' || RUBY_ENGINE == 'truffleruby'
+    ENV['LIQUID_C'] = '1'
 
     ENV['LIQUID_PARSER_MODE'] = 'lax'
     Rake::Task['base_test'].reenable

lib/liquid/context.rb

@@ -25,8 +25,6 @@ module Liquid
       @resource_limits  = resource_limits || ResourceLimits.new(Template.default_resource_limits)
       squash_instance_assigns_with_environments
 
-      @this_stack_used = false
-
       self.exception_renderer = Template.default_exception_renderer
       if rethrow_errors
         self.exception_renderer = ->(e) { raise }
@@ -111,19 +109,11 @@ module Liquid
     #   end
     #
     #   context['var]  #=> nil
-    def stack(new_scope = nil)
-      old_stack_used = @this_stack_used
-      if new_scope
-        push(new_scope)
-        @this_stack_used = true
-      else
-        @this_stack_used = false
-      end
-
+    def stack(new_scope = {})
+      push(new_scope)
       yield
     ensure
-      pop if @this_stack_used
-      @this_stack_used = old_stack_used
+      pop
     end
 
     def clear_instance_assigns
@@ -132,10 +122,6 @@ module Liquid
 
     # Only allow String, Numeric, Hash, Array, Proc, Boolean or <tt>Liquid::Drop</tt>
     def []=(key, value)
-      unless @this_stack_used
-        @this_stack_used = true
-        push({})
-      end
       @scopes[0][key] = value
     end
 

lib/liquid/tags/case.rb

@@ -39,16 +39,14 @@ module Liquid
     end
 
     def render_to_output_buffer(context, output)
-      context.stack do
-        execute_else_block = true
+      execute_else_block = true
 
-        @blocks.each do |block|
-          if block.else?
-            block.attachment.render_to_output_buffer(context, output) if execute_else_block
-          elsif block.evaluate(context)
-            execute_else_block = false
-            block.attachment.render_to_output_buffer(context, output)
-          end
+      @blocks.each do |block|
+        if block.else?
+          block.attachment.render_to_output_buffer(context, output) if execute_else_block
+        elsif block.evaluate(context)
+          execute_else_block = false
+          block.attachment.render_to_output_buffer(context, output)
         end
       end
 

lib/liquid/tags/cycle.rb

@@ -34,25 +34,23 @@ module Liquid
     def render_to_output_buffer(context, output)
       context.registers[:cycle] ||= {}
 
-      context.stack do
-        key = context.evaluate(@name)
-        iteration = context.registers[:cycle][key].to_i
+      key = context.evaluate(@name)
+      iteration = context.registers[:cycle][key].to_i
 
-        val = context.evaluate(@variables[iteration])
+      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
-
-        iteration += 1
-        iteration  = 0 if iteration >= @variables.size
-        context.registers[:cycle][key] = iteration
+      if val.is_a?(Array)
+        val = val.join
+      elsif !val.is_a?(String)
+        val = val.to_s
       end
 
+      output << val
+
+      iteration += 1
+      iteration  = 0 if iteration >= @variables.size
+      context.registers[:cycle][key] = iteration
+
       output
     end
 

lib/liquid/tags/if.rb

@@ -40,11 +40,9 @@ module Liquid
     end
 
     def render_to_output_buffer(context, output)
-      context.stack do
-        @blocks.each do |block|
-          if block.evaluate(context)
-            return block.attachment.render_to_output_buffer(context, output)
-          end
+      @blocks.each do |block|
+        if block.evaluate(context)
+          return block.attachment.render_to_output_buffer(context, output)
         end
       end
 

lib/liquid/tags/ifchanged.rb

@@ -1,14 +1,12 @@
 module Liquid
   class Ifchanged < Block
     def render_to_output_buffer(context, output)
-      context.stack do
-        block_output = ''
-        super(context, block_output)
+      block_output = ''
+      super(context, block_output)
 
-        if block_output != context.registers[:ifchanged]
-          context.registers[:ifchanged] = block_output
-          output << block_output
-        end
+      if block_output != context.registers[:ifchanged]
+        context.registers[:ifchanged] = block_output
+        output << block_output
       end
 
       output

lib/liquid/tags/unless.rb

@@ -7,18 +7,16 @@ module Liquid
   #
   class Unless < If
     def render_to_output_buffer(context, output)
-      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)
-        end
+      # 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)
+      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)
-          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)
         end
       end
 

liquid.gemspec

@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
   s.license     = "MIT"
   # s.description = "A secure, non-evaling end user template engine with aesthetic markup."
 
-  s.required_ruby_version     = ">= 2.1.0"
+  s.required_ruby_version     = ">= 2.4.0"
   s.required_rubygems_version = ">= 1.3.7"
 
   s.test_files  = Dir.glob("{test}/**/*")

performance/memory_profile.rb

@@ -30,6 +30,7 @@ class Profiler
     @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)

test/integration/tags/liquid_tag_test.rb

@@ -5,72 +5,72 @@ class LiquidTagTest < Minitest::Test
 
   def test_liquid_tag
     assert_template_result('1 2 3', <<~LIQUID, 'array' => [1, 2, 3])
-    {%- liquid
-      echo array | join: " "
-    -%}
+      {%- 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
+        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
+      {%- 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
-    -%}
+        echo " "
+        echo double_value
+      -%}
     LIQUID
 
     assert_template_result('abc', <<~LIQUID)
-    {%- liquid echo "a" -%}
-    b
-    {%- liquid echo "c" -%}
+      {%- 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 error no such tag -%}
     LIQUID
 
     assert_match_syntax_error("syntax error (line 7): Unknown tag 'error'", <<~LIQUID)
-    {{ test }}
+      {{ test }}
 
-    {%-
-    liquid
-      for value in array
+      {%-
+      liquid
+        for value in array
 
-        error no such tag
-      endfor
-    -%}
+          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
+        !!! 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
+        for value in array
+          echo 'forgot to close the for tag'
+      -%}
     LIQUID
   end
 
@@ -81,24 +81,24 @@ class LiquidTagTest < Minitest::Test
 
   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
+        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 -%}
+      {%- 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 %}
+      {% raw %}{% liquid echo 'test' %}{% endraw %}
     LIQUID
   end
 end

test/test_helper.rb

@@ -14,7 +14,7 @@ if env_mode = ENV['LIQUID_PARSER_MODE']
 end
 Liquid::Template.error_mode = mode
 
-if ENV['LIQUID-C'] == '1'
+if ENV['LIQUID_C'] == '1'
   puts "-- LIQUID C"
   require 'liquid/c'
 end