From 4c5251f127903628bbcec5ba4a1861fbf5d2efff Mon Sep 17 00:00:00 2001
From: Code Ahss <aycabta@gmail.com>
Date: Thu, 28 Sep 2017 19:16:32 +0900
Subject: [PATCH 1/2] Fix CodeFence with unintended Array for format

The rule ( !"`" Nonspacechar )+ for "format" variable becomes Array
but #intern is called for "format" variable and it means "format"
variable is expected as String, so this commit adds checking
instance_of?(String).
---
 lib/rdoc/markdown.kpeg | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/rdoc/markdown.kpeg b/lib/rdoc/markdown.kpeg
index 34f4de4657..e08aa5b828 100644
--- a/lib/rdoc/markdown.kpeg
+++ b/lib/rdoc/markdown.kpeg
@@ -1161,7 +1161,7 @@ CodeFence = &{ github? }
               @Newline
             )+ > Ticks3 @Sp @Newline*
             { verbatim = RDoc::Markup::Verbatim.new text
-              verbatim.format = format.intern if format
+              verbatim.format = format.intern if format.instance_of?(String)
               verbatim
             }
 

From 07492e929ba540f6006d55724d8d269de8c9aba0 Mon Sep 17 00:00:00 2001
From: Code Ahss <aycabta@gmail.com>
Date: Fri, 29 Sep 2017 00:03:17 +0900
Subject: [PATCH 2/2] Add test_code_fence_with_unintended_array

---
 test/test_rdoc_markdown.rb | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/test/test_rdoc_markdown.rb b/test/test_rdoc_markdown.rb
index 6c7bf4ae32..79b0175293 100644
--- a/test/test_rdoc_markdown.rb
+++ b/test/test_rdoc_markdown.rb
@@ -973,6 +973,14 @@ def test_strong
     assert_equal '<b>_emphasis_</b>', @parser.strong('_emphasis_')
   end
 
+  def test_code_fence_with_unintended_array
+    doc = parse '```<ruby>```'
+
+    expected = doc(verb('<ruby>'))
+
+    assert_equal expected, doc
+  end
+
   def parse text
     @parser.parse text
   end