Disable Liquid via front matter (#6824)

Merge pull request 6824

features/post_data.feature

@@ -251,6 +251,19 @@ Feature: Post data
     And I should see "Post categories: scifi and Movies" in "_site/scifi/movies/2009/03/27/star-wars.html"
     And I should see "Post categories: SciFi and movies" in "_site/scifi/movies/2013/03/17/star-trek.html"
 
+Scenario: Use page.render_with_liquid variable
+  Given I have a _posts directory
+  And I have the following posts:
+    | title           | render_with_liquid | date       | content                |
+    | Unrendered Post | false              | 2017-07-06 | Hello {{ page.title }} |
+    | Rendered Post   | true               | 2017-07-06 | Hello {{ page.title }} |
+  When I run jekyll build
+  Then I should get a zero exit status
+  And the _site directory should exist
+  And I should not see "Hello Unrendered Post" in "_site/2017/07/06/unrendered-post.html"
+  But I should see "Hello {{ page.title }}" in "_site/2017/07/06/unrendered-post.html"
+  And I should see "Hello Rendered Post" in "_site/2017/07/06/rendered-post.html"
+
   Scenario Outline: Use page.path variable
     Given I have a <dir>/_posts directory
     And I have the following post in "<dir>":

lib/jekyll/convertible.rb

@@ -160,6 +160,7 @@ module Jekyll
     #
     # Returns true if the file has Liquid Tags or Variables, false otherwise.
     def render_with_liquid?
+      return false if data["render_with_liquid"] == false
       Jekyll::Utils.has_liquid_construct?(content)
     end
 

lib/jekyll/document.rb

@@ -159,6 +159,7 @@ module Jekyll
     #   or if the document doesn't contain any Liquid Tags or Variables,
     #   true otherwise.
     def render_with_liquid?
+      return false if data["render_with_liquid"] == false
       !(coffeescript_file? || yaml_file? || !Utils.has_liquid_construct?(content))
     end
 

test/fixtures/no_liquid.erb

@@ -0,0 +1,4 @@
+---
+render_with_liquid: false
+---
+{% raw %}{% endraw %}

test/test_convertible.rb

@@ -73,5 +73,12 @@ class TestConvertible < JekyllUnitTest
       end
       refute_match(%r!Invalid permalink!, out)
     end
+
+    should "not parse Liquid if disabled in front matter" do
+      name = "no_liquid.erb"
+      @convertible.read_yaml(@base, name)
+      ret = @convertible.content.strip
+      assert_equal("{% raw %}{% endraw %}", ret)
+    end
   end
 end