Add test case for long git commit ids.

Author: jopereira

tests/casefiles/git-header-long.diff

@@ -0,0 +1,6 @@
+diff --git a/bugtrace/patch.py b/bugtrace/patch.py
+index 18910dfd..2456e34f 100644
+--- a/bugtrace/patch.py
++++ b/bugtrace/patch.py
+@@ -8,20 +8,30 @@
+

tests/test_patch.py

@@ -603,6 +603,23 @@ def test_git_header(self):
         results_main = wtp.patch.parse_header(text)
         self.assertEqual(results_main, expected)
 
+    def test_git_header_long(self):
+        with open('tests/casefiles/git-header-long.diff') as f:
+            text = f.read()
+
+        expected = wtp.patch.header(
+                index_path = None,
+                old_path = 'bugtrace/patch.py',
+                old_version = '18910dfd',
+                new_path = 'bugtrace/patch.py',
+                new_version = '2456e34f')
+
+        results = wtp.patch.parse_git_header(text)
+        self.assertEqual(results, expected)
+
+        results_main = wtp.patch.parse_header(text)
+        self.assertEqual(results_main, expected)
+
     def test_svn_header(self):
         with open('tests/casefiles/svn-header.diff') as f:
             text = f.read()