Introduce template factory

Make ruby 2.7 optional in CI

.travis.yml

@@ -15,6 +15,7 @@ matrix:
       name: Profiling Memory Usage
   allow_failures:
     - rvm: ruby-head
+    - rvm: 2.7
 
 branches:
   only:

lib/liquid.rb

@@ -80,6 +80,7 @@ require 'liquid/partial_cache'
 require 'liquid/usage'
 require 'liquid/register'
 require 'liquid/static_registers'
+require 'liquid/template_factory'
 
 # Load all the tags of the standard library
 #

lib/liquid/partial_cache.rb

@@ -12,7 +12,10 @@ module Liquid
 
       parse_context.partial = true
 
-      partial = Liquid::Template.parse(source, parse_context)
+      template_factory = (context.registers[:template_factory] ||= Liquid::TemplateFactory.new)
+      template = template_factory.for(template_name)
+
+      partial = template.parse(source, parse_context)
       cached_partials[template_name] = partial
     ensure
       parse_context.partial = false

lib/liquid/tags/include.rb

@@ -50,7 +50,19 @@ module Liquid
       template_name = context.evaluate(@template_name_expr)
       raise ArgumentError, options[:locale].t("errors.argument.include") unless template_name
 
-      partial = load_partial(template_name, context, parse_context)
+      partial = PartialCache.load(
+        template_name,
+        context: context,
+        parse_context: parse_context
+      )
+
+      context_variable_name = @alias_name || template_name.split('/').last
+
+      variable = if @variable_name_expr
+        context.evaluate(@variable_name_expr)
+      else
+        context.find_variable(template_name, raise_on_not_found: false)
+      end
 
       old_template_name = context.template_name
       old_partial       = context.partial
@@ -59,15 +71,7 @@ module Liquid
         context.partial       = true
         context.stack do
           @attributes.each do |key, value|
-            context[key] = evaluate(context, value)
-          end
-
-          context_variable_name = @alias_name || template_name.split('/').last
-
-          variable = if @variable_name_expr
-            evaluate(context, @variable_name_expr)
-          else
-            find_variable(context, template_name, raise_on_not_found: false)
+            context[key] = context.evaluate(value)
           end
 
           if variable.is_a?(Array)
@@ -99,24 +103,6 @@ module Liquid
         ] + @node.attributes.values
       end
     end
-
-    private
-
-    def evaluate(context, value)
-      context.evaluate(value)
-    end
-
-    def find_variable(context, *args)
-      context.find_variable(*args)
-    end
-
-    def load_partial(template_name, context, parse_context)
-      PartialCache.load(
-        template_name,
-        context: context,
-        parse_context: parse_context
-      )
-    end
   end
 
   Template.register_tag('include', Include)

lib/liquid/tags/render.rb

@@ -38,7 +38,11 @@ module Liquid
       template_name = context.evaluate(@template_name_expr)
       raise ArgumentError, options[:locale].t("errors.argument.include") unless template_name
 
-      partial = load_partial(template_name, context, parse_context)
+      partial = PartialCache.load(
+        template_name,
+        context: context,
+        parse_context: parse_context
+      )
 
       context_variable_name = @alias_name || template_name.split('/').last
 
@@ -49,14 +53,14 @@ module Liquid
         inner_context['forloop']    = forloop if forloop
 
         @attributes.each do |key, value|
-          inner_context[key] = evaluate(context, value)
+          inner_context[key] = context.evaluate(value)
         end
         inner_context[context_variable_name] = var unless var.nil?
         partial.render_to_output_buffer(inner_context, output)
         forloop&.send(:increment!)
       }
 
-      variable = @variable_name_expr ? evaluate(context, @variable_name_expr) : nil
+      variable = @variable_name_expr ? context.evaluate(@variable_name_expr) : nil
       if @for && variable.respond_to?(:each) && variable.respond_to?(:count)
         forloop = Liquid::ForloopDrop.new(template_name, variable.count, nil)
         variable.each { |var| render_partial_func.call(var, forloop) }
@@ -74,20 +78,6 @@ module Liquid
         ] + @node.attributes.values
       end
     end
-
-    private
-
-    def evaluate(context, value)
-      context.evaluate(value)
-    end
-
-    def load_partial(template_name, context, parse_context)
-      PartialCache.load(
-        template_name,
-        context: context,
-        parse_context: parse_context
-      )
-    end
   end
 
   Template.register_tag('render', Render)

lib/liquid/template_factory.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Liquid
+  class TemplateFactory
+    def for(_template_name)
+      Liquid::Template.new
+    end
+  end
+end

test/test_helper.rb

@@ -136,3 +136,16 @@ class StubFileSystem
     @values.fetch(template_path)
   end
 end
+
+class StubTemplateFactory
+  attr_reader :count
+
+  def initialize
+    @count = 0
+  end
+
+  def for(_template_name)
+    @count += 1
+    Liquid::Template.new
+  end
+end

test/unit/partial_cache_unit_test.rb

@@ -90,4 +90,39 @@ class PartialCacheUnitTest < Minitest::Test
     # but measuring file reads is an OK proxy for this.
     assert_equal(1, file_system.file_read_count)
   end
+
+  def test_uses_default_template_factory_when_no_template_factory_found_in_register
+    context = Liquid::Context.build(
+      registers: {
+        file_system: StubFileSystem.new('my_partial' => 'my partial body'),
+      }
+    )
+
+    partial = Liquid::PartialCache.load(
+      'my_partial',
+      context: context,
+      parse_context: Liquid::ParseContext.new
+    )
+
+    assert_equal('my partial body', partial.render)
+  end
+
+  def test_uses_template_factory_register_if_present
+    template_factory = StubTemplateFactory.new
+    context = Liquid::Context.build(
+      registers: {
+        file_system: StubFileSystem.new('my_partial' => 'my partial body'),
+        template_factory: template_factory,
+      }
+    )
+
+    partial = Liquid::PartialCache.load(
+      'my_partial',
+      context: context,
+      parse_context: Liquid::ParseContext.new
+    )
+
+    assert_equal('my partial body', partial.render)
+    assert_equal(1, template_factory.count)
+  end
 end

test/unit/template_factory_unit_test.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class TemplateFactoryUnitTest < Minitest::Test
+  include Liquid
+
+  def test_for_returns_liquid_template_instance
+    template = TemplateFactory.new.for("anything")
+    assert_instance_of(Liquid::Template, template)
+  end
+end