From ef51a395528afaf6eae6e2065f8481bd65922e09 Mon Sep 17 00:00:00 2001
From: akashnimare <svnitakash@gmail.com>
Date: Fri, 22 Dec 2017 17:21:08 +0530
Subject: [PATCH] markdown: Update regex for strikethrough.

This uses the correct regex for strikethrough. Also, added
a test to make sure that strikethrough works when it contains
link with whitespace.

Fixes #7596.
---
 zerver/fixtures/markdown_test_cases.json | 6 ++++++
 zerver/lib/bugdown/__init__.py           | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/zerver/fixtures/markdown_test_cases.json b/zerver/fixtures/markdown_test_cases.json
index 92c046d1f1..afb41d537c 100644
--- a/zerver/fixtures/markdown_test_cases.json
+++ b/zerver/fixtures/markdown_test_cases.json
@@ -188,6 +188,12 @@
       "expected_output": "<p>I <del> like software </del> love hardware</p>",
       "text_content": "I  like software  love hardware"
     },
+    {
+      "name": "strikthrough_link",
+      "input": "~~test http://xx.xx link~~",
+      "expected_output": "<p><del>test <a href=\"http://xx.xx\" target=\"_blank\" title=\"http://xx.xx\">http://xx.xx</a> link</del></p>",
+      "text_content": "test http://xx.xx link"
+    },
     {
       "name": "underscore_disabled",
       "input": "_foo_",
diff --git a/zerver/lib/bugdown/__init__.py b/zerver/lib/bugdown/__init__.py
index ccb8866d85..0b9cca504c 100644
--- a/zerver/lib/bugdown/__init__.py
+++ b/zerver/lib/bugdown/__init__.py
@@ -1395,7 +1395,7 @@ class Bugdown(markdown.Extension):
         # Custom strikethrough syntax: ~~foo~~
         md.inlinePatterns.add('del',
                               markdown.inlinepatterns.SimpleTagPattern(
-                                  r'(?<!~)(\~\~)([^~{0}\n]+?)\2(?!~)', 'del'), '>strong')
+                                  r'(?<!~)(\~\~)([^~\n]+?)(\~\~)(?!~)', 'del'), '>strong')
 
         # Text inside ** must start and end with a word character
         # it need for things like "const char *x = (char *)y"