# Python test set -- part 5, built-in exceptions
import os
import sys
import unittest
import pickle, cPickle
from test.test_support import (TESTFN, unlink, run_unittest, captured_stderr,
check_warnings, cpython_only)
from test.test_pep352 import ignore_deprecation_warnings
class BrokenStrException(Exception):
def __str__(self):
raise Exception("str() is broken")
__repr__ = __str__ # Python 2's PyErr_WriteUnraisable() uses repr()
# XXX This is not really enough, each *operation* should be tested!
class ExceptionTests(unittest.TestCase):
def testReload(self):
# Reloading the built-in exceptions module failed prior to Py2.2, while it
# should act the same as reloading built-in sys.
try:
from imp import reload
import exceptions
reload(exceptions)
except ImportError, e:
self.fail("reloading exceptions: %s" % e)
def raise_catch(self, exc, excname):
try:
raise exc, "spam"
except exc, err:
buf1 = str(err)
try:
raise exc("spam")
except exc, err:
buf2 = str(err)
self.assertEqual(buf1, buf2)
self.assertEqual(exc.__name__, excname)
def testRaising(self):
self.raise_catch(AttributeError, "AttributeError")
self.assertRaises(AttributeError, getattr, sys, "undefined_attribute")
self.raise_catch(EOFError, "EOFError")
fp = open(TESTFN, 'w')
fp.close()
fp = open(TESTFN, 'r')
savestdin = sys.stdin
try:
try:
sys.stdin = fp
x = raw_input()
except EOFError:
pass
finally:
sys.stdin = savestdin
fp.close()
unlink(TESTFN)
self.raise_catch(IOError, "IOError")
self.assertRaises(IOError, open, 'this file does not exist', 'r')
self.raise_catch(ImportError, "ImportError")
self.assertRaises(ImportError, __import__, "undefined_module")
self.raise_catch(IndexError, "IndexError")
x = []
self.assertRaises(IndexError, x.__getitem__, 10)
self.raise_catch(KeyError, "KeyError")
x = {}
self.assertRaises(KeyError, x.__getitem__, 'key')
self.raise_catch(KeyboardInterrupt, "KeyboardInterrupt")
self.raise_catch(MemoryError, "MemoryError")
self.raise_catch(NameError, "NameError")
try: x = undefined_variable
except NameError: pass
self.raise_catch(OverflowError, "OverflowError")
x = 1
for dummy in range(128):
x += x # this simply shouldn't blow up
self.raise_catch(RuntimeError, "RuntimeError")
self.raise_catch(SyntaxError, "SyntaxError")
try: exec '/\n'
except SyntaxError: pass
self.raise_catch(IndentationError, "IndentationError")
self.raise_catch(TabError, "TabError")
# can only be tested under -tt, and is the only test for -tt
#try: compile("try:\n\t1.0/0.0\n \t1.0/0.0\nfinally:\n pass\n", '<string>', 'exec')
#except TabError: pass
#else: self.fail("TabError not raised")
self.raise_catch(SystemError, "SystemError")
self.raise_catch(SystemExit, "SystemExit")
self.assertRaises(SystemExit, sys.exit, 0)
self.raise_catch(TypeError, "TypeError")
try: [] + ()
except TypeError: pass
self.raise_catch(ValueError, "ValueError")
self.assertRaises(ValueError, chr, 10000)
self.raise_catch(ZeroDivisionError, "ZeroDivisionError")
try: x = 1 // 0
except ZeroDivisionError: pass
self.raise_catch(Exception, "Exception")
try: x = 1 // 0
except Exception, e: pass
def testSyntaxErrorMessage(self):
# make sure the right exception message is raised for each of
# these code fragments
def ckmsg(src, msg):
try:
compile(src, '<fragment>', 'exec')
except SyntaxError, e:
if e.msg != msg:
self.fail("expected %s, got %s" % (msg, e.msg))
else:
self.fail("failed to get expected SyntaxError")
s = '''while 1:
try:
pass
finally:
continue'''
if not sys.platform.startswith('java'):
ckmsg(s, "'continue' not supported inside 'finally' clause")
s = '''if 1:
try:
continue
except:
pass'''
ckmsg(s, "'continue' not properly in loop")
ckmsg("continue\n", "'continue' not properly in loop")
@cpython_only
def testSettingException(self):
# test that setting an exception at the C level works even if the
# exception object can't be constructed.
class BadException:
def __init__(self_):
raise RuntimeError, "can't instantiate BadException"
def test_capi1():
import _testcapi
try:
_testcapi.raise_exception(BadException, 1)
except TypeError, err:
exc, err, tb = sys.exc_info()
co = tb.tb_frame.f_code
self.assertEqual(co.co_name, "test_capi1")
self.assertTrue(co.co_filename.endswith('test_exceptions'+os.extsep+'py'))
else:
self.fail("Expected exception")
def test_capi2():
import _testcapi
try:
_testcapi.raise_exception(BadException, 0)
except RuntimeError, err:
exc, err, tb = sys.exc_info()
co = tb.tb_frame.f_code
self.assertEqual(co.co_name, "__init__")
self.assertTrue(co.co_filename.endswith('test_exceptions'+os.extsep+'py'))
co2 = tb.tb_frame.f_back.f_code
self.assertEqual(co2.co_name, "test_capi2")
else:
self.fail("Expected exception")
if not sys.platform.startswith('java'):
test_capi1()
test_capi2()
def test_WindowsError(self):
try:
WindowsError
except NameError:
pass
else:
self.assertEqual(str(WindowsError(1001)),
"1001")
self.assertEqual(str(WindowsError(1001, "message")),
"[Error 1001] message")
self.assertEqual(WindowsError(1001, "message").errno, 22)
self.assertEqual(WindowsError(1001, "message").winerror, 1001)
@ignore_deprecation_warnings
def testAttributes(self):
# test that exception attributes are happy
exceptionList = [
(BaseException, (), {'message' : '', 'args' : ()}),
(BaseException, (1, ), {'message' : 1, 'args' : (1,)}),
(BaseException, ('foo',),
{'message' : 'foo', 'args' : ('foo',)}),
(BaseException, ('foo', 1),
{'message' : '', 'args' : ('foo', 1)}),
(SystemExit, ('foo',),
{'message' : 'foo', 'args' : ('foo',), 'code' : 'foo'}),
(IOError, ('foo',),
{'message' : 'foo', 'args' : ('foo',), 'filename' : None,
'errno' : None, 'strerror' : None}),
(IOError, ('foo', 'bar'),
{'message' : '', 'args' : ('foo', 'bar'), 'filename' : None,
'errno' : 'foo', 'strerror' : 'bar'}),
(IOError, ('foo', 'bar', 'baz'),
{'message' : '', 'args' : ('foo', 'bar'), 'filename' : 'baz',
'errno' : 'foo', 'strerror' : 'bar'}),
(IOError, ('foo', 'bar', 'baz', 'quux'),
{'message' : '', 'args' : ('foo', 'bar', 'baz', 'quux')}),
(EnvironmentError, ('errnoStr', 'strErrorStr', 'filenameStr'),
{'message' : '', 'args' : ('errnoStr', 'strErrorStr'),
'strerror' : 'strErrorStr', 'errno' : 'errnoStr',
'filename' : 'filenameStr'}),
(EnvironmentError, (1, 'strErrorStr', 'filenameStr'),
{'message' : '', 'args' : (1, 'strErrorStr'), 'errno' : 1,
'strerror' : 'strErrorStr', 'filename' : 'filenameStr'}),
(SyntaxError, (), {'message' : '', 'msg' : None, 'text' : None,
'filename' : None, 'lineno' : None, 'offset' : None,
'print_file_and_line' : None}),
(SyntaxError, ('msgStr',),
{'message' : 'msgStr', 'args' : ('msgStr',), 'text' : None,
'print_file_and_line' : None, 'msg' : 'msgStr',
'filename' : None, 'lineno' : None, 'offset' : None}),
(SyntaxError, ('msgStr', ('filenameStr', 'linenoStr', 'offsetStr',
'textStr')),
{'message' : '', 'offset' : 'offsetStr', 'text' : 'textStr',
'args' : ('msgStr', ('filenameStr', 'linenoStr',
'offsetStr', 'textStr')),
'print_file_and_line' : None, 'msg' : 'msgStr',
'filename' : 'filenameStr', 'lineno' : 'linenoStr'}),
(SyntaxError, ('msgStr', 'filenameStr', 'linenoStr', 'offsetStr',
'textStr', 'print_file_and_lineStr'),
{'message' : '', 'text' : None,
'args' : ('msgStr', 'filenameStr', 'linenoStr', 'offsetStr',
'textStr', 'print_file_and_lineStr'),
'print_file_and_line' : None, 'msg' : 'msgStr',
'filename' : None, 'lineno' : None, 'offset' : None}),
(UnicodeError, (), {'message' : '', 'args' : (),}),
(UnicodeEncodeError, ('ascii', u'a', 0, 1, 'ordinal not in range'),
{'message' : '', 'args' : ('ascii', u'a', 0, 1,
'ordinal not in range'),
'encoding' : 'ascii', 'object' : u'a',
'start' : 0, 'reason' : 'ordinal not in range'}),
(UnicodeDecodeError, ('ascii', '\xff', 0, 1, 'ordinal not in range'),
{'message' : '', 'args' : ('ascii', '\xff', 0, 1,
'ordinal not in range'),
'encoding' : 'ascii', 'object' : '\xff',
'start' : 0, 'reason' : 'ordinal not in range'}),
(UnicodeTranslateError, (u"\u3042", 0, 1, "ouch"),
{'message' : '', 'args' : (u'\u3042', 0, 1, 'ouch'),
'object' : u'\u3042', 'reason' : 'ouch',
'start' : 0, 'end' : 1}),
]
try:
exceptionList.append(
(WindowsError, (1, 'strErrorStr', 'filenameStr'),
{'message' : '', 'args' : (1, 'strErrorStr'),
'strerror' : 'strErrorStr', 'winerror' : 1,
'errno' : 22, 'filename' : 'filenameStr'})
)
except NameError:
pass
for exc, args, expected in exceptionList:
try:
raise exc(*args)
except BaseException, e:
if type(e) is not exc:
raise
# Verify module name
self.assertEqual(type(e).__module__, 'exceptions')
# Verify no ref leaks in Exc_str()
s = str(e)
for checkArgName in expected:
self.assertEqual(repr(getattr(e, checkArgName)),
repr(expected[checkArgName]),
'exception "%s", attribute "%s"' %
(repr(e), checkArgName))
# test for pickling support
for p in pickle, cPickle:
for protocol in range(p.HIGHEST_PROTOCOL + 1):
new = p.loads(p.dumps(e, protocol))
for checkArgName in expected:
got = repr(getattr(new, checkArgName))
want = repr(expected[checkArgName])
self.assertEqual(got, want,
'pickled "%r", attribute "%s"' %
(e, checkArgName))
def testDeprecatedMessageAttribute(self):
# Accessing BaseException.message and relying on its value set by
# BaseException.__init__ triggers a deprecation warning.
exc = BaseException("foo")
with check_warnings(("BaseException.message has been deprecated "
"as of Python 2.6", DeprecationWarning)) as w:
self.assertEqual(exc.message, "foo")
self.assertEqual(len(w.warnings), 1)
def testRegularMessageAttribute(self):
# Accessing BaseException.message after explicitly setting a value
# for it does not trigger a deprecation warning.
exc = BaseException("foo")
exc.message = "bar"
with check_warnings(quiet=True) as w:
self.assertEqual(exc.message, "bar")
self.assertEqual(len(w.warnings), 0)
# Deleting the message is supported, too.
del exc.message
with self.assertRaises(AttributeError):
exc.message
@ignore_deprecation_warnings
def testPickleMessageAttribute(self):
# Pickling with message attribute must work, as well.
e = Exception("foo")
f = Exception("foo")
f.message = "bar"
for p in pickle, cPickle:
ep = p.loads(p.dumps(e))
self.assertEqual(ep.message, "foo")
fp = p.loads(p.dumps(f))
self.assertEqual(fp.message, "bar")
@ignore_deprecation_warnings
def testSlicing(self):
# Test that you can slice an exception directly instead of requiring
# going through the 'args' attribute.
args = (1, 2, 3)
exc = BaseException(*args)
self.assertEqual(exc[:], args)
self.assertEqual(exc.args[:], args)
def testKeywordArgs(self):
# test that builtin exception don't take keyword args,
# but user-defined subclasses can if they want
self.assertRaises(TypeError, BaseException, a=1)
class DerivedException(BaseException):
def __init__(self, fancy_arg):
BaseException.__init__(self)
self.fancy_arg = fancy_arg
x = DerivedException(fancy_arg=42)
self.assertEqual(x.fancy_arg, 42)
def testInfiniteRecursion(self):
def f():
return f()
self.assertRaises(RuntimeError, f)
def g():
try:
return g()
except ValueError:
return -1
# The test prints an unraisable recursion error when
# doing "except ValueError", this is because subclass
# checking has recursion checking too.
with captured_stderr():
try:
g()
except RuntimeError:
pass
except:
self.fail("Should have raised KeyError")
else:
self.fail("Should have raised KeyError")
def testUnicodeStrUsage(self):
# Make sure both instances and classes have a str and unicode
# representation.
self.assertTrue(str(Exception))
self.assertTrue(unicode(Exception))
self.assertTrue(str(Exception('a')))
self.assertTrue(unicode(Exception(u'a')))
self.assertTrue(unicode(Exception(u'\xe1')))
def testUnicodeChangeAttributes(self):
# See issue 7309. This was a crasher.
u = UnicodeEncodeError('baz', u'xxxxx', 1, 5, 'foo')
self.assertEqual(str(u), "'baz' codec can't encode characters in position 1-4: foo")
u.end = 2
self.assertEqual(str(u), "'baz' codec can't encode character u'\\x78' in position 1: foo")
u.end = 5
u.reason = 0x345345345345345345
self.assertEqual(str(u), "'baz' codec can't encode characters in position 1-4: 965230951443685724997")
u.encoding = 4000
self.assertEqual(str(u), "'4000' codec can't encode characters in position 1-4: 965230951443685724997")
u.start = 1000
self.assertEqual(str(u), "'4000' codec can't encode characters in position 1000-4: 965230951443685724997")
u = UnicodeDecodeError('baz', 'xxxxx', 1, 5, 'foo')
self.assertEqual(str(u), "'baz' codec can't decode bytes in position 1-4: foo")
u.end = 2
self.assertEqual(str(u), "'baz' codec can't decode byte 0x78 in position 1: foo")
u.end = 5
u.reason = 0x345345345345345345
self.assertEqual(str(u), "'baz' codec can't decode bytes in position 1-4: 965230951443685724997")
u.encoding = 4000
self.assertEqual(str(u), "'4000' codec can't decode bytes in position 1-4: 965230951443685724997")
u.start = 1000
self.assertEqual(str(u), "'4000' codec can't decode bytes in position 1000-4: 965230951443685724997")
u = UnicodeTranslateError(u'xxxx', 1, 5, 'foo')
self.assertEqual(str(u), "can't translate characters in position 1-4: foo")
u.end = 2
self.assertEqual(str(u), "can't translate character u'\\x78' in position 1: foo")
u.end = 5
u.reason = 0x345345345345345345
self.assertEqual(str(u), "can't translate characters in position 1-4: 965230951443685724997")
u.start = 1000
self.assertEqual(str(u), "can't translate characters in position 1000-4: 965230951443685724997")
def test_unicode_errors_no_object(self):
# See issue #21134.
klasses = UnicodeEncodeError, UnicodeDecodeError, UnicodeTranslateError
for klass in klasses:
self.assertEqual(str(klass.__new__(klass)), "")
def test_badisinstance(self):
# Bug #2542: if issubclass(e, MyException) raises an exception,
# it should be ignored
class Meta(type):
def __subclasscheck__(cls, subclass):
raise ValueError()
class MyException(Exception):
__metaclass__ = Meta
pass
with captured_stderr() as stderr:
try:
raise KeyError()
except MyException, e:
self.fail("exception should not be a MyException")
except KeyError:
pass
except:
self.fail("Should have raised KeyError")
else:
self.fail("Should have raised KeyError")
with captured_stderr() as stderr:
def g():
try:
return g()
except RuntimeError:
return sys.exc_info()
e, v, tb = g()
self.assertTrue(e is RuntimeError, e)
self.assertIn("maximum recursion depth exceeded", str(v))
def test_new_returns_invalid_instance(self):
# See issue #11627.
class MyException(Exception):
def __new__(cls, *args):
return object()
with self.assertRaises(TypeError):
raise MyException
def test_assert_with_tuple_arg(self):
try:
assert False, (3,)
except AssertionError as e:
self.assertEqual(str(e), "(3,)")
def test_bad_exception_clearing(self):
# See issue 16445: use of Py_XDECREF instead of Py_CLEAR in
# BaseException_set_message gave a possible way to segfault the
# interpreter.
class Nasty(str):
def __del__(message):
del e.message
e = ValueError(Nasty("msg"))
e.args = ()
del e.message
# Helper class used by TestSameStrAndUnicodeMsg
class ExcWithOverriddenStr(Exception):
"""Subclass of Exception that accepts a keyword 'msg' arg that is
returned by __str__. 'msg' won't be included in self.args"""
def __init__(self, *args, **kwargs):
self.msg = kwargs.pop('msg') # msg should always be present
super(ExcWithOverriddenStr, self).__init__(*args, **kwargs)
def __str__(self):
return self.msg
class TestSameStrAndUnicodeMsg(unittest.TestCase):
"""unicode(err) should return the same message of str(err). See #6108"""
def check_same_msg(self, exc, msg):
"""Helper function that checks if str(exc) == unicode(exc) == msg"""
self.assertEqual(str(exc), msg)
self.assertEqual(str(exc), unicode(exc))
def test_builtin_exceptions(self):
"""Check same msg for built-in exceptions"""
# These exceptions implement a __str__ method that uses the args
# to create a better error message. unicode(e) should return the same
# message.
exceptions = [
SyntaxError('invalid syntax', ('<string>', 1, 3, '2+*3')),
IOError(2, 'No such file or directory'),
KeyError('both should have the same quotes'),
UnicodeDecodeError('ascii', '\xc3\xa0', 0, 1,
'ordinal not in range(128)'),
UnicodeEncodeError('ascii', u'\u1234', 0, 1,
'ordinal not in range(128)')
]
for exception in exceptions:
self.assertEqual(str(exception), unicode(exception))
def test_0_args(self):
"""Check same msg for Exception with 0 args"""
# str() and unicode() on an Exception with no args should return an
# empty string
self.check_same_msg(Exception(), '')
def test_0_args_with_overridden___str__(self):
"""Check same msg for exceptions with 0 args and overridden __str__"""
# str() and unicode() on an exception with overridden __str__ that
# returns an ascii-only string should return the same string
for msg in ('foo', u'foo'):
self.check_same_msg(ExcWithOverriddenStr(msg=msg), msg)
# if __str__ returns a non-ascii unicode string str() should fail
# but unicode() should return the unicode string
e = ExcWithOverriddenStr(msg=u'f\xf6\xf6') # no args
self.assertRaises(UnicodeEncodeError, str, e)
self.assertEqual(unicode(e), u'f\xf6\xf6')
def test_1_arg(self):
"""Check same msg for Exceptions with 1 arg"""
for arg in ('foo', u'foo'):
self.check_same_msg(Exception(arg), arg)
# if __str__ is not overridden and self.args[0] is a non-ascii unicode
# string, str() should try to return str(self.args[0]) and fail.
# unicode() should return unicode(self.args[0]) and succeed.
e = Exception(u'f\xf6\xf6')
self.assertRaises(UnicodeEncodeError, str, e)
self.assertEqual(unicode(e), u'f\xf6\xf6')
def test_1_arg_with_overridden___str__(self):
"""Check same msg for exceptions with overridden __str__ and 1 arg"""
# when __str__ is overridden and __unicode__ is not implemented
# unicode(e) returns the same as unicode(e.__str__()).
for msg in ('foo', u'foo'):
self.check_same_msg(ExcWithOverriddenStr('arg', msg=msg), msg)
# if __str__ returns a non-ascii unicode string, str() should fail
# but unicode() should succeed.
e = ExcWithOverriddenStr('arg', msg=u'f\xf6\xf6') # 1 arg
self.assertRaises(UnicodeEncodeError, str, e)
self.assertEqual(unicode(e), u'f\xf6\xf6')
def test_many_args(self):
"""Check same msg for Exceptions with many args"""
argslist = [
(3, 'foo'),
(1, u'foo', 'bar'),
(4, u'f\xf6\xf6', u'bar', 'baz')
]
# both str() and unicode() should return a repr() of the args
for args in argslist:
self.check_same_msg(Exception(*args), repr(args))
def test_many_args_with_overridden___str__(self):
"""Check same msg for exceptions with overridden __str__ and many args"""
# if __str__ returns an ascii string / ascii unicode string
# both str() and unicode() should succeed
for msg in ('foo', u'foo'):
e = ExcWithOverriddenStr('arg1', u'arg2', u'f\xf6\xf6', msg=msg)
self.check_same_msg(e, msg)
# if __str__ returns a non-ascii unicode string, str() should fail
# but unicode() should succeed
e = ExcWithOverriddenStr('arg1', u'f\xf6\xf6', u'arg3', # 3 args
msg=u'f\xf6\xf6')
self.assertRaises(UnicodeEncodeError, str, e)
self.assertEqual(unicode(e), u'f\xf6\xf6')
@cpython_only
def test_exception_with_doc(self):
import _testcapi
doc2 = "This is a test docstring."
doc4 = "This is another test docstring."
self.assertRaises(SystemError, _testcapi.make_exception_with_doc,
"error1")
# test basic usage of PyErr_NewException
error1 = _testcapi.make_exception_with_doc("_testcapi.error1")
self.assertIs(type(error1), type)
self.assertTrue(issubclass(error1, Exception))
self.assertIsNone(error1.__doc__)
# test with given docstring
error2 = _testcapi.make_exception_with_doc("_testcapi.error2", doc2)
self.assertEqual(error2.__doc__, doc2)
# test with explicit base (without docstring)
error3 = _testcapi.make_exception_with_doc("_testcapi.error3",
base=error2)
self.assertTrue(issubclass(error3, error2))
# test with explicit base tuple
class C(object):
pass
error4 = _testcapi.make_exception_with_doc("_testcapi.error4", doc4,
(error3, C))
self.assertTrue(issubclass(error4, error3))
self.assertTrue(issubclass(error4, C))
self.assertEqual(error4.__doc__, doc4)
# test with explicit dictionary
error5 = _testcapi.make_exception_with_doc("_testcapi.error5", "",
error4, {'a': 1})
self.assertTrue(issubclass(error5, error4))
self.assertEqual(error5.a, 1)
self.assertEqual(error5.__doc__, "")
def test_unraisable(self):
# Issue #22836: PyErr_WriteUnraisable() should give sensible reports
class BrokenDel:
def __del__(self):
exc = ValueError("del is broken")
# In Python 3, the following line would be in the report:
raise exc
class BrokenRepr(BrokenDel):
def __repr__(self):
raise AttributeError("repr() is broken")
class BrokenExceptionDel:
def __del__(self):
exc = BrokenStrException()
# In Python 3, the following line would be in the report:
raise exc
for test_class in (BrokenDel, BrokenRepr, BrokenExceptionDel):
obj = test_class()
with captured_stderr() as stderr:
del obj
report = stderr.getvalue()
self.assertRegexpMatches(report, "Exception.* ignored")
if test_class is BrokenRepr:
self.assertIn("<object repr() failed>", report)
else:
self.assertIn("__del__", report)
if test_class is BrokenExceptionDel:
self.assertIn("BrokenStrException", report)
self.assertIn("<exception repr() failed>", report)
else:
self.assertIn("ValueError", report)
self.assertIn("del is broken", report)
self.assertTrue(report.endswith("\n"))
def test_unhandled(self):
# Check for sensible reporting of unhandled exceptions
for exc_type in (ValueError, BrokenStrException):
try:
exc = exc_type("test message")
# The following line is included in the traceback report:
raise exc
except exc_type:
with captured_stderr() as stderr:
sys.__excepthook__(*sys.exc_info())
report = stderr.getvalue()
self.assertIn("test_exceptions.py", report)
self.assertIn("raise exc", report)
self.assertIn(exc_type.__name__, report)
if exc_type is BrokenStrException:
self.assertIn("<exception str() failed>", report)
else:
self.assertIn("test message", report)
self.assertTrue(report.endswith("\n"))
def test_main():
run_unittest(ExceptionTests, TestSameStrAndUnicodeMsg)
if __name__ == '__main__':
test_main()
