The problem is in `difflib.ndiff` function. When the string does not have a trailing newline, we get an unreadable output.
After applying my patch, the following is the output of test2.py (submitted by Elena.Oat).



FFFFFFFF
======================================================================
FAIL: test_notrailingnewline_0 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 8, in test_notrailingnewline_0
    self.assertEqual("abcDefehiJkl", "abcdefGhijkl")
AssertionError: 'abcDefehiJkl' != 'abcdefGhijkl'
- abcDefehiJkl
?    ^  ^  ^
+ abcdefGhijkl
?    ^  ^  ^


======================================================================
FAIL: test_notrailingnewline_1 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 14, in test_notrailingnewline_1
    self.assertEqual("a\nbcdf", "a\nbddf")
AssertionError: 'a\nbcdf' != 'a\nbddf'
  a
- bcdf
?  ^
+ bddf
?  ^


======================================================================
FAIL: test_notrailingnewline_2 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 18, in test_notrailingnewline_2
    self.assertEqual("a\nbcdf", "a\nbddg")
AssertionError: 'a\nbcdf' != 'a\nbddg'
  a
- bcdf
+ bddg


======================================================================
FAIL: test_starting_and_ending_newline_0 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 12, in test_starting_and_ending_newline_0
    self.assertEqual("\nabcDefehiJkl\n", "\nabcdefGhijkl\n")
AssertionError: '\nabcDefehiJkl\n' != '\nabcdefGhijkl\n'
  
- abcDefehiJkl
?    ^  ^  ^
+ abcdefGhijkl
?    ^  ^  ^


======================================================================
FAIL: test_startingnewline_0 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 10, in test_startingnewline_0
    self.assertEqual("\nabcDefehiJkl", "\nabcdefGhijkl")
AssertionError: '\nabcDefehiJkl' != '\nabcdefGhijkl'
  
- abcDefehiJkl
?    ^  ^  ^
+ abcdefGhijkl
?    ^  ^  ^


======================================================================
FAIL: test_trailingnewline_0 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 6, in test_trailingnewline_0
    self.assertEqual("abcDefehiJkl\n", "abcdefGhijkl\n")
AssertionError: 'abcDefehiJkl\n' != 'abcdefGhijkl\n'
- abcDefehiJkl
?    ^  ^  ^
+ abcdefGhijkl
?    ^  ^  ^


======================================================================
FAIL: test_trailingnewline_1 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 16, in test_trailingnewline_1
    self.assertEqual("a\nbcdf\n", "a\nbddf\n")
AssertionError: 'a\nbcdf\n' != 'a\nbddf\n'
  a
- bcdf
?  ^
+ bddf
?  ^


======================================================================
FAIL: test_trailingnewline_2 (__main__.AssertEqualTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 20, in test_trailingnewline_2
    self.assertEqual("a\nbcdf\n", "a\nbddg\n")
AssertionError: 'a\nbcdf\n' != 'a\nbddg\n'
  a
- bcdf
+ bddg


----------------------------------------------------------------------
Ran 8 tests in 0.004s

FAILED (failures=8)