--- you can reply above this line --- New issue 279: Output on assertion failure of object comparisons could be better https://bitbucket.org/hpk42/pytest/issue/279/output-on-assertion-failure-of-object
Brianna Laugher: I [mentioned](http://mail.python.org/pipermail/pytest-dev/2013-March/002208.html) on pytest-dev that the output when tests fail from assertions around objects, especially lists/dicts/sets of objects, could be improved. In particular, comparisons appear with diff text which has ... "Skipping x identical leading characters in diff" (ie truncated) but there is no way to get the "full diff" - the truncated diff is usually fine when comparing strings directly but you need the full string to understand it properly when comparing, say, dicts. [testfixtures.compare](http://mail.python.org/pipermail/pytest-dev/2013-March/002208.html) is more verbose, could be a useful starting point. Here is an example that might be useful. ``` #!python from collections import namedtuple import datetime from testfixtures import compare TR = namedtuple('TR', 'start end') def test_Foo(): todayStart = datetime.datetime.today() todayEnd = todayStart + datetime.timedelta(hours=24) todayEndLater = todayEnd + datetime.timedelta(seconds=5) a = {frozenset('abc'): TR(todayStart, todayEndLater), frozenset('efg'): TR(todayStart, todayEnd)} b = {frozenset('abc'): TR(todayStart, todayEnd), frozenset('efg'): TR(todayStart, todayEnd)} compare(a, b) # assert a == b ``` Native pytest output: ``` #! > assert a == b E assert {frozenset(['... 19, 456379))} == {frozenset(['a... 19, 456379))} E Skipping 121 identical leading characters in diff E Skipping 147 identical trailing characters in diff E - 1, 8, 35, 24, 456379) E ? ^^ E + 1, 8, 35, 19, 456379) E ? ^^ ``` testfixtures.compare output: ``` #! > compare(a, b) ../GFESuite-Builds/Release/release/lib/python2.7/site-packages/testfixtures/comparison.py:268: in compare > raise AssertionError(message) E AssertionError: dict not as expected: E E same: E [frozenset(['e', 'g', 'f'])] E E values differ: E frozenset(['a', 'c', 'b']): TR(start=datetime.datetime(2013, 3, 20, 8, 35, 36, 430903), end=datetime.datetime(2013, 3, 21, 8, 35, 41, 430903)) != TR(start=datetime.datetime(2013, 3, 20, 8, 35, 36, 430903), end=datetime.datetime(2013, 3, 21, 8, 35, 36, 430903)) ``` At least with the latter I have a clue about which key/value is causing the problem. This is with pytest-2.2.3 but I don't think it's improved in 2.3. -- This is an issue notification from bitbucket.org. You are receiving this either because you are the owner of the issue, or you are following the issue. _______________________________________________ pytest-commit mailing list pytest-commit@python.org http://mail.python.org/mailman/listinfo/pytest-commit
