Fix error message for comparing single line strings in unittest.TestCase.assertEqual.
Issue 9174.
diff --git a/Lib/unittest/case.py b/Lib/unittest/case.py
index 3bc2b3d..03346a1 100644
--- a/Lib/unittest/case.py
+++ b/Lib/unittest/case.py
@@ -940,9 +940,14 @@
'Second argument is not a string'))
if first != second:
- standardMsg = '%s != %s' % (safe_repr(first, True), safe_repr(second, True))
- diff = '\n' + ''.join(difflib.ndiff(first.splitlines(True),
- second.splitlines(True)))
+ firstlines = first.splitlines(True)
+ secondlines = second.splitlines(True)
+ if len(firstlines) == 1 and first.strip('\r\n') == first:
+ firstlines = [first + '\n']
+ secondlines = [second + '\n']
+ standardMsg = '%s != %s' % (safe_repr(first, True),
+ safe_repr(second, True))
+ diff = '\n' + ''.join(difflib.ndiff(firstlines, secondlines))
standardMsg = self._truncateMessage(standardMsg, diff)
self.fail(self._formatMessage(msg, standardMsg))
diff --git a/Lib/unittest/test/test_case.py b/Lib/unittest/test/test_case.py
index 00883c9..1800f2e 100644
--- a/Lib/unittest/test/test_case.py
+++ b/Lib/unittest/test/test_case.py
@@ -841,6 +841,21 @@
# so can't use assertEqual either. Just use assertTrue.
self.assertTrue(sample_text_error == error)
+ def testAsertEqualSingleLine(self):
+ sample_text = "laden swallows fly slowly"
+ revised_sample_text = "unladen swallows fly quickly"
+ sample_text_error = """\
+- laden swallows fly slowly
+? ^^^^
++ unladen swallows fly quickly
+? ++ ^^^^^
+"""
+ try:
+ self.assertEqual(sample_text, revised_sample_text)
+ except self.failureException as e:
+ error = str(e).split('\n', 1)[1]
+ self.assertTrue(sample_text_error == error)
+
def testAssertIsNone(self):
self.assertIsNone(None)
self.assertRaises(self.failureException, self.assertIsNone, False)