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

Avoid hash with default values due to inconsistent marshaling

.rubocop.yml

@@ -7,8 +7,6 @@ AllCops:
 
 Metrics/BlockNesting:
   Max: 3
-  Exclude:
-    - 'lib/liquid/block_body.rb'
 
 Metrics/ModuleLength:
   Enabled: false

lib/liquid/block_body.rb

@@ -15,38 +15,35 @@ module Liquid
     def parse(tokenizer, parse_context)
       parse_context.line_number = tokenizer.line_number
       while token = tokenizer.shift
-        unless token.empty?
-          case
-          when token.start_with?(TAGSTART)
-            whitespace_handler(token, parse_context)
-            if token =~ FullToken
-              tag_name = $1
-              markup = $2
-              # fetch the tag from registered blocks
-              if tag = registered_tags[tag_name]
-                new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
-                @blank &&= new_tag.blank?
-                @nodelist << new_tag
-              else
-                # end parsing if we reach an unknown tag and let the caller decide
-                # determine how to proceed
-                return yield tag_name, markup
-              end
-            else
-              raise_missing_tag_terminator(token, parse_context)
-            end
-          when token.start_with?(VARSTART)
-            whitespace_handler(token, parse_context)
-            @nodelist << create_variable(token, parse_context)
-            @blank = false
-          else
-            if parse_context.trim_whitespace
-              token.lstrip!
-            end
-            parse_context.trim_whitespace = false
-            @nodelist << token
-            @blank &&= !!(token =~ /\A\s*\z/)
+        next if token.empty?
+        case
+        when token.start_with?(TAGSTART)
+          whitespace_handler(token, parse_context)
+          unless token =~ FullToken
+            raise_missing_tag_terminator(token, parse_context)
           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
+            return yield tag_name, markup
+          end
+          new_tag = tag.parse(tag_name, markup, tokenizer, parse_context)
+          @blank &&= new_tag.blank?
+          @nodelist << new_tag
+        when token.start_with?(VARSTART)
+          whitespace_handler(token, parse_context)
+          @nodelist << create_variable(token, parse_context)
+          @blank = false
+        else
+          if parse_context.trim_whitespace
+            token.lstrip!
+          end
+          parse_context.trim_whitespace = false
+          @nodelist << token
+          @blank &&= !!(token =~ /\A\s*\z/)
         end
         parse_context.line_number = tokenizer.line_number
       end

lib/liquid/context.rb

@@ -171,7 +171,9 @@ module Liquid
       if scope.nil?
         @environments.each do |e|
           variable = lookup_and_evaluate(e, key, raise_on_not_found: raise_on_not_found)
-          unless variable.nil?
+          # When lookup returned a value OR there is no value but the lookup also did not raise
+          # then it is the value we are looking for.
+          if !variable.nil? || @strict_variables && raise_on_not_found
             scope = e
             break
           end

lib/liquid/extensions.rb

@@ -7,6 +7,12 @@ class String # :nodoc:
   end
 end
 
+class Symbol # :nodoc:
+  def to_liquid
+    to_s
+  end
+end
+
 class Array # :nodoc:
   def to_liquid
     self

lib/liquid/standardfilters.rb

@@ -201,12 +201,14 @@ module Liquid
 
     # 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

lib/liquid/tags/cycle.rb

@@ -30,11 +30,11 @@ module Liquid
     end
 
     def render(context)
-      context.registers[:cycle] ||= Hash.new(0)
+      context.registers[:cycle] ||= {}
 
       context.stack do
         key = context.evaluate(@name)
-        iteration = context.registers[:cycle][key]
+        iteration = context.registers[:cycle][key].to_i
         result = context.evaluate(@variables[iteration])
         iteration += 1
         iteration  = 0 if iteration >= @variables.size

lib/liquid/tags/for.rb

@@ -120,7 +120,7 @@ module Liquid
     private
 
     def collection_segment(context)
-      offsets = context.registers[:for] ||= Hash.new(0)
+      offsets = context.registers[:for] ||= {}
 
       from = if @from == :continue
         offsets[@name].to_i
@@ -129,7 +129,7 @@ module Liquid
       end
 
       collection = context.evaluate(@collection_name)
-      collection = collection.step(1).to_a if collection.is_a?(Range)
+      collection = collection.to_a if collection.is_a?(Range)
 
       limit = context.evaluate(@limit)
       to = limit ? limit.to_i + from : nil

test/integration/standard_filter_test.rb

@@ -362,8 +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
 

test/integration/tags/for_tag_test.rb

@@ -48,10 +48,6 @@ HERE
 
   def test_for_with_variable_range
     assert_template_result(' 1  2  3 ', '{%for item in (1..foobar) %} {{item}} {%endfor%}', "foobar" => 3)
-    assert_template_result(' 1.0  2.0  3.0 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1..3.0))
-    assert_template_result(' 1.0  2.0  3.0 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1.0..3))
-    assert_template_result(' 1.0  2.0  3.0 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1.0..3.0))
-    assert_template_result(' 1.5  2.5 ', '{%for item in foobar %} {{item}} {%endfor%}', "foobar" => (1.5..3))
   end
 
   def test_for_with_hash_value_range

test/integration/template_test.rb

@@ -261,6 +261,15 @@ class TemplateTest < Minitest::Test
     assert_equal 'Liquid error: undefined variable d', t.errors[2].message
   end
 
+  def test_nil_value_does_not_raise
+    Liquid::Template.error_mode = :strict
+    t = Template.parse("some{{x}}thing")
+    result = t.render!({ 'x' => nil }, strict_variables: true)
+
+    assert_equal 0, t.errors.count
+    assert_equal 'something', result
+  end
+
   def test_undefined_variables_raise
     t = Template.parse("{{x}} {{y}} {{z.a}} {{z.b}} {{z.c.d}}")
 

test/integration/variable_test.rb

@@ -89,4 +89,8 @@ class VariableTest < Minitest::Test
   def test_multiline_variable
     assert_equal 'worked', Template.parse("{{\ntest\n}}").render!('test' => 'worked')
   end
+
+  def test_render_symbol
+    assert_template_result 'bar', '{{ foo }}', 'foo' => :bar
+  end
 end