New issue 453: assertion rewriting fails with object whose __repr__ contains
'{\n'
https://bitbucket.org/hpk42/pytest/issue/453/assertion-rewriting-fails-with-object
Tim Sampson:
Consider the following:
```
#!python
resp = self.user.service.content.get_journal(initial_sync=True)
> assert resp.count != 0
v2/test_journal.py:144:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _
explanation = 'assert 0\n{0 = Headers: \nContent: {\n "count": 0,\n
"items": [],\n "total": 0,\n "journal_max": 2158\n}.count\n} != 0'
def format_explanation(explanation):
"""This formats an explanation
Normally all embedded newlines are escaped, however there are
three exceptions: \n{, \n} and \n~. The first two are intended
cover nested explanations, see function and attribute explanations
for examples (.visit_Call(), visit_Attribute()). The last one is
for when one explanation needs to span multiple lines, e.g. when
displaying diffs.
"""
explanation = _collapse_false(explanation)
lines = _split_explanation(explanation)
> result = _format_lines(lines)
/usr/local/lib/python2.6/dist-packages/_pytest/assertion/util.py:31:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/_ _
lines = ['assert 0', '{0 = Headers: \\nContent: {\\n "count": 0,\\n
"items": [],\\n "total": 0,\\n "journal_max": 2158', '}.count', '} !=
0']
def _format_lines(lines):
"""Format the individual lines
This will replace the '{', '}' and '~' characters of our mini
formatting language with the proper 'where ...', 'and ...' and ' +
...' text, taking care of indentation along the way.
Return a list of formatted lines.
"""
result = lines[:1]
stack = [0]
stackcnt = [0]
for line in lines[1:]:
if line.startswith('{'):
if stackcnt[-1]:
s = u('and ')
else:
s = u('where ')
stack.append(len(result))
stackcnt[-1] += 1
stackcnt.append(0)
result.append(u(' +') + u(' ')*(len(stack)-1) + s +
line[1:])
elif line.startswith('}'):
assert line.startswith('}')
stack.pop()
stackcnt.pop()
> result[stack[-1]] += line[1:]
E IndexError: list index out of range
/usr/local/lib/python2.6/dist-packages/_pytest/assertion/util.py:108:
/IndexError
```
I'm sure how this can work. As repr(resp) contains the pretty printed json body
i.e. it contains '{\n' and '\n}' which apparently confuses format_explanation.
I could of course get around this by setting assert=plain and that works fine,
but the bare asserts are so nice that I'd like to keep them. Also I guess I
could change our code to not include the problematic chars in repr but I would
rather not do that either.
_______________________________________________
pytest-commit mailing list
pytest-commit@python.org
https://mail.python.org/mailman/listinfo/pytest-commit
