__repr__ hack for domish.Element doesn't work because assert uses str()

Submitted by Will Thompson @wjt

Assigned to Telepathy bugs list

Link to original bug (#18179)

Description

servicetest.py contains the following:

# hack to ease debugging
domish.Element.__repr__ = domish.Element.toXml

The intention is that code like:

assert element['foo'] == bar, element

should produce the stringified xml of element when the assertion fails. This does not in fact work, as assert uses str() not repr().

Overriding str in the same way yields bizarro exceptions:

Traceback (most recent call last): File "/build/buildd/python2.4-2.4.5/Modules/pyexpat.c", line 639, in EndElement

File "/usr/lib/python2.4/site-packages/twisted/words/xish/domish.py", line 780, in _onEndElement self.ElementEvent(self.currElem) File "/usr/lib/python2.4/site-packages/twisted/words/xish/xmlstream.py", line 106, in onElement self.dispatch(element) File "/usr/lib/python2.4/site-packages/twisted/words/xish/utility.py", line 316, in dispatch callbacklist.callback(obj) --- <exception caught here> --- File "/usr/lib/python2.4/site-packages/twisted/words/xish/utility.py", line 106, in callback methodwrapper(*args, **kwargs) File "/usr/lib/python2.4/site-packages/twisted/words/xish/utility.py", line 27, in call self.method(*nargs, **nkwargs) File "/home/will/src/Telepathy/telepathy-gabble/tests/twisted/gabbletest.py", line 75, in secondIq assert map(str, username) == [self.username] exceptions.AssertionError: Traceback (most recent call last): File "/home/will/src/Telepathy/telepathy-gabble/tests/twisted/gabbletest.py", line 316, in exec_test_deferred fun(queue, bus, conn, stream) File "./muc/test-muc.py", line 16, in test q.expect('dbus-signal', signal='StatusChanged', args=[0, 1]) File "/home/will/src/Telepathy/telepathy-gabble/tests/twisted/servicetest.py", line 217, in expect event = self.wait() File "/home/will/src/Telepathy/telepathy-gabble/tests/twisted/servicetest.py", line 286, in wait raise TimeoutError TimeoutError