From bae4b1985d921d50799da8108657d4432a7f34f7 Mon Sep 17 00:00:00 2001
From: Jean-Philippe Lang <jp_lang@yahoo.fr>
Date: Thu, 15 Oct 2015 18:31:34 +0000
Subject: [PATCH] Fixed unsafe call to #casecmp (#20369, #21000).

git-svn-id: http://svn.redmine.org/redmine/trunk@14676 e93f8b46-1217-0410-a6f0-8f06a7374b81
---
 app/helpers/application_helper.rb            | 2 +-
 test/unit/helpers/application_helper_test.rb | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 4bf9e15c8..60aad08a2 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -609,7 +609,7 @@ module ApplicationHelper
       parsed << text
       if tag
         if closing
-          if tags.last.casecmp(tag) == 0
+          if tags.last && tags.last.casecmp(tag) == 0
             tags.pop
           end
         else
diff --git a/test/unit/helpers/application_helper_test.rb b/test/unit/helpers/application_helper_test.rb
index 27c711dda..883e9d33e 100644
--- a/test/unit/helpers/application_helper_test.rb
+++ b/test/unit/helpers/application_helper_test.rb
@@ -994,6 +994,12 @@ EXPECTED
     assert_equal expected.gsub(%r{[\r\n\t]}, ''), textilizable(raw).gsub(%r{[\r\n\t]}, '')
   end
 
+  def test_unbalanced_closing_pre_tag_should_not_error
+    assert_nothing_raised do
+      textilizable("unbalanced</pre>")
+    end
+  end
+
   def test_syntax_highlight
     raw = <<-RAW
 <pre><code class="ruby">
-- 
2.39.5