Only recognize the expected output as an exception if it *starts* with
a traceback message. I.e., examples that raise exceptions may no
longer generate pre-exception output. This restores the behavior of
doctest in python 2.3. The ability to check pre-exception output is
being removed because it makes the documentation simpler; and because
there are very few use cases for it.
diff --git a/Lib/doctest.py b/Lib/doctest.py
index 43f21b2..01f7cb3 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -1281,15 +1281,14 @@
# A regular expression for handling `want` strings that contain
# expected exceptions. It divides `want` into three pieces:
- # - the pre-exception output (`want`)
# - the traceback header line (`hdr`)
+ # - the traceback stack (`stack`)
# - the exception message (`msg`), as generated by
# traceback.format_exception_only()
# `msg` may have multiple lines. We assume/require that the
# exception message is the first non-indented line starting with a word
# character following the traceback header line.
_EXCEPTION_RE = re.compile(r"""
- (?P<want> .*?) # suck up everything until traceback header
# Grab the traceback header. Different versions of Python have
# said different things on the first traceback line.
^(?P<hdr> Traceback\ \(
@@ -1297,9 +1296,9 @@
| innermost\ last
) \) :
)
- \s* $ # toss trailing whitespace on traceback header
- .*? # don't blink: absorb stuff until a line *starts* with \w
- ^ (?P<msg> \w+ .*)
+ \s* $ # toss trailing whitespace on the header.
+ (?P<stack> .*?) # don't blink: absorb stuff until...
+ ^ (?P<msg> \w+ .*) # a line *starts* with alphanum.
""", re.VERBOSE | re.MULTILINE | re.DOTALL)
def __run(self, test, compileflags, out):
@@ -1374,13 +1373,10 @@
exc_info)
failures += 1
else:
- e_want, e_msg = m.group('want', 'msg')
- # The test passes iff the pre-exception output and
- # the exception description match the values given
- # in `want`.
- if (self._checker.check_output(e_want, got,
- self.optionflags) and
- self._checker.check_output(e_msg, exc_msg,
+ # The test passes iff the expected exception
+ # message (`m.group('msg')`) matches the actual
+ # exception message (`exc_msg`).
+ if (self._checker.check_output(m.group('msg'), exc_msg,
self.optionflags)):
self.report_success(out, test, example,
got + _exception_traceback(exc_info))
diff --git a/Lib/test/test_doctest.py b/Lib/test/test_doctest.py
index d5e9ef5..5d0cf90 100644
--- a/Lib/test/test_doctest.py
+++ b/Lib/test/test_doctest.py
@@ -623,8 +623,10 @@
>>> doctest.DocTestRunner(verbose=False).run(test)
(0, 2)
-An example may generate output before it raises an exception; if it
-does, then the output must match the expected output:
+An example may not generate output before it raises an exception; if
+it does, then the traceback message will not be recognized as
+signaling an expected exception, so the example will be reported as an
+unexpected exception:
>>> def f(x):
... '''
@@ -636,7 +638,15 @@
... '''
>>> test = doctest.DocTestFinder().find(f)[0]
>>> doctest.DocTestRunner(verbose=False).run(test)
- (0, 2)
+ ... # doctest: +ELLIPSIS
+ **********************************************************************
+ Line 3, in f
+ Failed example:
+ print 'pre-exception output', x/0
+ Exception raised:
+ ...
+ ZeroDivisionError: integer division or modulo by zero
+ (1, 2)
Exception messages may contain newlines: