WIP: Experiments with liquid 5.x

.github/workflows/ci.yml

@@ -14,16 +14,24 @@ jobs:
   ci:
     name: "Run Tests (${{ matrix.label }})"
     runs-on: "ubuntu-latest"
+    env:
+      LIQUID_VERSION: ${{ matrix.liquid_version }}
     strategy:
       fail-fast: false
       matrix:
         include:
           - label: Ruby 2.7
             ruby_version: "2.7"
+          - label: Ruby 2.7 with Liquid v4
+            ruby_version: "2.7"
+            liquid_version: "~> 4.0"
           - label: Ruby 3.0
             ruby_version: "3.0"
           - label: Ruby 3.1.2
             ruby_version: "3.1.2"
+          - label: Ruby 3.1.2 with Liquid v4
+            ruby_version: "3.1.2"
+            liquid_version: "~> 4.0"
           - label: JRuby 9.4.0.0
             ruby_version: "jruby-9.4.0.0"
     steps:

Gemfile

@@ -3,6 +3,12 @@
 source "https://rubygems.org"
 gemspec :name => "jekyll"
 
+if ENV["LIQUID_VERSION"].to_s.empty?
+  gem "liquid", "~> 5.3.0"
+else
+  gem "liquid", ENV["LIQUID_VERSION"]
+end
+
 gem "rake", "~> 13.0"
 
 group :development do
@@ -86,7 +92,6 @@ group :jekyll_optional_dependencies do
 
   platforms :ruby, :mswin, :mingw, :x64_mingw do
     gem "classifier-reborn", "~> 2.2"
-    gem "liquid-c", "~> 4.0"
     gem "yajl-ruby", "~> 1.4"
   end
 

appveyor.yml

@@ -21,6 +21,10 @@ environment:
     - RUBY_FOLDER_VER: "27"
       TZINFO_VERSION: "~> 2.0"
       TEST_SUITE: "test"
+    - RUBY_FOLDER_VER: "27"
+      LIQUID_VERSION: "~> 4.0"
+      TZINFO_VERSION: "~> 2.0"
+      TEST_SUITE: "test"
     - RUBY_FOLDER_VER: "27"
       TEST_SUITE: "default-site"
     - RUBY_FOLDER_VER: "27"

jekyll.gemspec

@@ -40,7 +40,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency("jekyll-watch",          "~> 2.0")
   s.add_runtime_dependency("kramdown",              "~> 2.3", ">= 2.3.1")
   s.add_runtime_dependency("kramdown-parser-gfm",   "~> 1.0")
-  s.add_runtime_dependency("liquid",                "~> 4.0")
+  s.add_runtime_dependency("liquid",                ">= 4.0", "< 5.4")
   s.add_runtime_dependency("mercenary",             ">= 0.3.6", "< 0.5")
   s.add_runtime_dependency("pathutil",              "~> 0.9")
   s.add_runtime_dependency("rouge",                 ">= 3.0", "< 5.0")

lib/jekyll.rb

@@ -180,6 +180,7 @@ def sanitized_path(base_directory, questionable_path)
 
     # Conditional optimizations
     Jekyll::External.require_if_present("liquid/c")
+    require "jekyll/liquid_expr_method_literal" if Liquid::VERSION.start_with?("5.")
   end
 end
 

lib/jekyll/liquid_expr_method_literal.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+module Liquid
+  class Expression
+    class MethodLiteral
+      attr_reader :method_name, :to_s
+      alias_method :to_liquid, :to_s
+
+      def initialize(method_name, to_s)
+        @method_name = method_name
+        @to_s = to_s
+      end
+    end
+
+    PATCHED_LITERALS = Liquid::Expression::LITERALS.dup.tap do |obj|
+      obj["blank"] = MethodLiteral.new(:blank?, "").freeze
+      obj["empty"] = MethodLiteral.new(:empty?, "").freeze
+    end
+
+    remove_const :LITERALS
+    LITERALS = PATCHED_LITERALS.freeze
+
+    remove_const :PATCHED_LITERALS
+  end
+end

lib/jekyll/tags/include.rb

@@ -254,7 +254,8 @@ def tag_includes_dirs(context)
       end
 
       def page_path(context)
-        page, site = context.registers.values_at(:page, :site)
+        page = context.registers.fetch(:page, nil)
+        site = context.registers.fetch(:site, nil)
         return site.source unless page
 
         site.in_source_dir File.dirname(resource_path(page, site))