fix test related to "not in"

CHANGELOG

@@ -15,7 +15,7 @@ Changes between 2.0.0 and 2.0.1.devX
   with python3 (now that nose-1.0 supports python3)
 - remove somewhat surprising "same-conftest" detection because
   it ignores conftest.py when they appear in several subdirs.
-- improve assertions ("not in"), thanks Floris
+- improve assertions ("not in"), thanks Floris Bruynooghe
 - improve behaviour/warnings when running on top of "python -OO"
   (assertions and docstrings are turned off, leading to potential
   false positives)

testing/test_assertion.py

@@ -116,8 +116,7 @@ class TestAssert_reprcompare:
 
 def test_reprcompare_notin():
     detail = plugin.pytest_assertrepr_compare('not in', 'foo', 'aaafoobbb')[1:]
-    assert '- aaabbb' in detail
-    assert '+ aaafoobbb' in detail
+    assert detail == ["'foo' is contained here:", '  aaafoobbb', '?    +++']
 
 @needsnewassert
 def test_pytest_assertrepr_compare_integration(testdir):