The unittest.TestCase.assertEqual() now displays the differences in lists,

tuples, dicts and sets on failure.

Many new handy type and comparison specific assert* methods have been added
that fail with error messages actually useful for debugging.  Contributed in
by Google and completed with help from mfoord and GvR at PyCon 2009 sprints.

Discussion lives in http://bugs.python.org/issue2578.

Lib/test/test_gc.py

@@ -244,7 +244,7 @@ class GCTests(unittest.TestCase):
     # - the call to assertEqual somehow avoids building its args tuple
     def test_get_count(self):
         # Avoid future allocation of method object
-        assertEqual = self.assertEqual
+        assertEqual = self._baseAssertEqual
         gc.collect()
         assertEqual(gc.get_count(), (0, 0, 0))
         a = dict()

Lib/test/test_struct.py

@@ -227,6 +227,7 @@ class StructTest(unittest.TestCase):
             BUGGY_RANGE_CHECK = "bBhHiIlL"
 
             def __init__(self, formatpair, bytesize):
+                super(IntTester, self).__init__(methodName='test_one')
                 self.assertEqual(len(formatpair), 2)
                 self.formatpair = formatpair
                 for direction in "<>!=":

Misc/NEWS

@@ -217,6 +217,15 @@ Library
 
 - Issue #1034053: unittest now supports skipping tests and expected failures.
 
+- The unittest.TestCase.assertRaises() method now returns a context manager when
+  not given a callable so that code to be tested can be written inline using
+  a with statement.
+
+- The unittest.TestCase.assertEqual() now displays the differences in lists,
+  tuples, dicts and sets on failure.  Many new handy type and comparison
+  specific assert* methods have been added that fail with error messages
+  actually useful for debugging.  Contributed in part by Google.  [Issue #2578]
+
 - Issue #5068: Fixed the tarfile._BZ2Proxy.read() method that would loop
   forever on incomplete input. That caused tarfile.open() to hang when used
   with mode 'r' or 'r:bz2' and a fileobj argument that contained no data or