cpython/Lib/unittest/case.py

1480 lines
57 KiB
Python

"""Test case implementation"""
import sys
import functools
import difflib
import pprint
import re
import warnings
import collections
import contextlib
import traceback
import types
from . import result
from .util import (strclass, safe_repr, _count_diff_all_purpose,
_count_diff_hashable, _common_shorten_repr)
__unittest = True
_subtest_msg_sentinel = object()
DIFF_OMITTED = ('\nDiff is %s characters long. '
'Set self.maxDiff to None to see it.')
class SkipTest(Exception):
"""
Raise this exception in a test to skip it.
Usually you can use TestCase.skipTest() or one of the skipping decorators
instead of raising this directly.
"""
class _ShouldStop(Exception):
"""
The test should stop.
"""
class _UnexpectedSuccess(Exception):
"""
The test was supposed to fail, but it didn't!
"""
class _Outcome(object):
def __init__(self, result=None):
self.expecting_failure = False
self.result = result
self.result_supports_subtests = hasattr(result, "addSubTest")
self.success = True
self.expectedFailure = None
@contextlib.contextmanager
def testPartExecutor(self, test_case, subTest=False):
old_success = self.success
self.success = True
try:
yield
except KeyboardInterrupt:
raise
except SkipTest as e:
self.success = False
_addSkip(self.result, test_case, str(e))
except _ShouldStop:
pass
except:
exc_info = sys.exc_info()
if self.expecting_failure:
self.expectedFailure = exc_info
else:
self.success = False
if subTest:
self.result.addSubTest(test_case.test_case, test_case, exc_info)
else:
_addError(self.result, test_case, exc_info)
# explicitly break a reference cycle:
# exc_info -> frame -> exc_info
exc_info = None
else:
if subTest and self.success:
self.result.addSubTest(test_case.test_case, test_case, None)
finally:
self.success = self.success and old_success
def _addSkip(result, test_case, reason):
addSkip = getattr(result, 'addSkip', None)
if addSkip is not None:
addSkip(test_case, reason)
else:
warnings.warn("TestResult has no addSkip method, skips not reported",
RuntimeWarning, 2)
result.addSuccess(test_case)
def _addError(result, test, exc_info):
if result is not None and exc_info is not None:
if issubclass(exc_info[0], test.failureException):
result.addFailure(test, exc_info)
else:
result.addError(test, exc_info)
def _id(obj):
return obj
def _enter_context(cm, addcleanup):
# We look up the special methods on the type to match the with
# statement.
cls = type(cm)
try:
enter = cls.__enter__
exit = cls.__exit__
except AttributeError:
raise TypeError(f"'{cls.__module__}.{cls.__qualname__}' object does "
f"not support the context manager protocol") from None
result = enter(cm)
addcleanup(exit, cm, None, None, None)
return result
_module_cleanups = []
def addModuleCleanup(function, /, *args, **kwargs):
"""Same as addCleanup, except the cleanup items are called even if
setUpModule fails (unlike tearDownModule)."""
_module_cleanups.append((function, args, kwargs))
def enterModuleContext(cm):
"""Same as enterContext, but module-wide."""
return _enter_context(cm, addModuleCleanup)
def doModuleCleanups():
"""Execute all module cleanup functions. Normally called for you after
tearDownModule."""
exceptions = []
while _module_cleanups:
function, args, kwargs = _module_cleanups.pop()
try:
function(*args, **kwargs)
except Exception as exc:
exceptions.append(exc)
if exceptions:
# Swallows all but first exception. If a multi-exception handler
# gets written we should use that here instead.
raise exceptions[0]
def skip(reason):
"""
Unconditionally skip a test.
"""
def decorator(test_item):
if not isinstance(test_item, type):
@functools.wraps(test_item)
def skip_wrapper(*args, **kwargs):
raise SkipTest(reason)
test_item = skip_wrapper
test_item.__unittest_skip__ = True
test_item.__unittest_skip_why__ = reason
return test_item
if isinstance(reason, types.FunctionType):
test_item = reason
reason = ''
return decorator(test_item)
return decorator
def skipIf(condition, reason):
"""
Skip a test if the condition is true.
"""
if condition:
return skip(reason)
return _id
def skipUnless(condition, reason):
"""
Skip a test unless the condition is true.
"""
if not condition:
return skip(reason)
return _id
def expectedFailure(test_item):
test_item.__unittest_expecting_failure__ = True
return test_item
def _is_subtype(expected, basetype):
if isinstance(expected, tuple):
return all(_is_subtype(e, basetype) for e in expected)
return isinstance(expected, type) and issubclass(expected, basetype)
class _BaseTestCaseContext:
def __init__(self, test_case):
self.test_case = test_case
def _raiseFailure(self, standardMsg):
msg = self.test_case._formatMessage(self.msg, standardMsg)
raise self.test_case.failureException(msg)
class _AssertRaisesBaseContext(_BaseTestCaseContext):
def __init__(self, expected, test_case, expected_regex=None):
_BaseTestCaseContext.__init__(self, test_case)
self.expected = expected
self.test_case = test_case
if expected_regex is not None:
expected_regex = re.compile(expected_regex)
self.expected_regex = expected_regex
self.obj_name = None
self.msg = None
def handle(self, name, args, kwargs):
"""
If args is empty, assertRaises/Warns is being used as a
context manager, so check for a 'msg' kwarg and return self.
If args is not empty, call a callable passing positional and keyword
arguments.
"""
try:
if not _is_subtype(self.expected, self._base_type):
raise TypeError('%s() arg 1 must be %s' %
(name, self._base_type_str))
if not args:
self.msg = kwargs.pop('msg', None)
if kwargs:
raise TypeError('%r is an invalid keyword argument for '
'this function' % (next(iter(kwargs)),))
return self
callable_obj, *args = args
try:
self.obj_name = callable_obj.__name__
except AttributeError:
self.obj_name = str(callable_obj)
with self:
callable_obj(*args, **kwargs)
finally:
# bpo-23890: manually break a reference cycle
self = None
class _AssertRaisesContext(_AssertRaisesBaseContext):
"""A context manager used to implement TestCase.assertRaises* methods."""
_base_type = BaseException
_base_type_str = 'an exception type or tuple of exception types'
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, tb):
if exc_type is None:
try:
exc_name = self.expected.__name__
except AttributeError:
exc_name = str(self.expected)
if self.obj_name:
self._raiseFailure("{} not raised by {}".format(exc_name,
self.obj_name))
else:
self._raiseFailure("{} not raised".format(exc_name))
else:
traceback.clear_frames(tb)
if not issubclass(exc_type, self.expected):
# let unexpected exceptions pass through
return False
# store exception, without traceback, for later retrieval
self.exception = exc_value.with_traceback(None)
if self.expected_regex is None:
return True
expected_regex = self.expected_regex
if not expected_regex.search(str(exc_value)):
self._raiseFailure('"{}" does not match "{}"'.format(
expected_regex.pattern, str(exc_value)))
return True
__class_getitem__ = classmethod(types.GenericAlias)
class _AssertWarnsContext(_AssertRaisesBaseContext):
"""A context manager used to implement TestCase.assertWarns* methods."""
_base_type = Warning
_base_type_str = 'a warning type or tuple of warning types'
def __enter__(self):
# The __warningregistry__'s need to be in a pristine state for tests
# to work properly.
for v in list(sys.modules.values()):
if getattr(v, '__warningregistry__', None):
v.__warningregistry__ = {}
self.warnings_manager = warnings.catch_warnings(record=True)
self.warnings = self.warnings_manager.__enter__()
warnings.simplefilter("always", self.expected)
return self
def __exit__(self, exc_type, exc_value, tb):
self.warnings_manager.__exit__(exc_type, exc_value, tb)
if exc_type is not None:
# let unexpected exceptions pass through
return
try:
exc_name = self.expected.__name__
except AttributeError:
exc_name = str(self.expected)
first_matching = None
for m in self.warnings:
w = m.message
if not isinstance(w, self.expected):
continue
if first_matching is None:
first_matching = w
if (self.expected_regex is not None and
not self.expected_regex.search(str(w))):
continue
# store warning for later retrieval
self.warning = w
self.filename = m.filename
self.lineno = m.lineno
return
# Now we simply try to choose a helpful failure message
if first_matching is not None:
self._raiseFailure('"{}" does not match "{}"'.format(
self.expected_regex.pattern, str(first_matching)))
if self.obj_name:
self._raiseFailure("{} not triggered by {}".format(exc_name,
self.obj_name))
else:
self._raiseFailure("{} not triggered".format(exc_name))
class _OrderedChainMap(collections.ChainMap):
def __iter__(self):
seen = set()
for mapping in self.maps:
for k in mapping:
if k not in seen:
seen.add(k)
yield k
class TestCase(object):
"""A class whose instances are single test cases.
By default, the test code itself should be placed in a method named
'runTest'.
If the fixture may be used for many test cases, create as
many test methods as are needed. When instantiating such a TestCase
subclass, specify in the constructor arguments the name of the test method
that the instance is to execute.
Test authors should subclass TestCase for their own tests. Construction
and deconstruction of the test's environment ('fixture') can be
implemented by overriding the 'setUp' and 'tearDown' methods respectively.
If it is necessary to override the __init__ method, the base class
__init__ method must always be called. It is important that subclasses
should not change the signature of their __init__ method, since instances
of the classes are instantiated automatically by parts of the framework
in order to be run.
When subclassing TestCase, you can set these attributes:
* failureException: determines which exception will be raised when
the instance's assertion methods fail; test methods raising this
exception will be deemed to have 'failed' rather than 'errored'.
* longMessage: determines whether long messages (including repr of
objects used in assert methods) will be printed on failure in *addition*
to any explicit message passed.
* maxDiff: sets the maximum length of a diff in failure messages
by assert methods using difflib. It is looked up as an instance
attribute so can be configured by individual tests if required.
"""
failureException = AssertionError
longMessage = True
maxDiff = 80*8
# If a string is longer than _diffThreshold, use normal comparison instead
# of difflib. See #11763.
_diffThreshold = 2**16
# Attribute used by TestSuite for classSetUp
_classSetupFailed = False
_class_cleanups = []
def __init__(self, methodName='runTest'):
"""Create an instance of the class that will use the named test
method when executed. Raises a ValueError if the instance does
not have a method with the specified name.
"""
self._testMethodName = methodName
self._outcome = None
self._testMethodDoc = 'No test'
try:
testMethod = getattr(self, methodName)
except AttributeError:
if methodName != 'runTest':
# we allow instantiation with no explicit method name
# but not an *incorrect* or missing method name
raise ValueError("no such test method in %s: %s" %
(self.__class__, methodName))
else:
self._testMethodDoc = testMethod.__doc__
self._cleanups = []
self._subtest = None
# Map types to custom assertEqual functions that will compare
# instances of said type in more detail to generate a more useful
# error message.
self._type_equality_funcs = {}
self.addTypeEqualityFunc(dict, 'assertDictEqual')
self.addTypeEqualityFunc(list, 'assertListEqual')
self.addTypeEqualityFunc(tuple, 'assertTupleEqual')
self.addTypeEqualityFunc(set, 'assertSetEqual')
self.addTypeEqualityFunc(frozenset, 'assertSetEqual')
self.addTypeEqualityFunc(str, 'assertMultiLineEqual')
def addTypeEqualityFunc(self, typeobj, function):
"""Add a type specific assertEqual style function to compare a type.
This method is for use by TestCase subclasses that need to register
their own type equality functions to provide nicer error messages.
Args:
typeobj: The data type to call this function on when both values
are of the same type in assertEqual().
function: The callable taking two arguments and an optional
msg= argument that raises self.failureException with a
useful error message when the two arguments are not equal.
"""
self._type_equality_funcs[typeobj] = function
def addCleanup(self, function, /, *args, **kwargs):
"""Add a function, with arguments, to be called when the test is
completed. Functions added are called on a LIFO basis and are
called after tearDown on test failure or success.
Cleanup items are called even if setUp fails (unlike tearDown)."""
self._cleanups.append((function, args, kwargs))
def enterContext(self, cm):
"""Enters the supplied context manager.
If successful, also adds its __exit__ method as a cleanup
function and returns the result of the __enter__ method.
"""
return _enter_context(cm, self.addCleanup)
@classmethod
def addClassCleanup(cls, function, /, *args, **kwargs):
"""Same as addCleanup, except the cleanup items are called even if
setUpClass fails (unlike tearDownClass)."""
cls._class_cleanups.append((function, args, kwargs))
@classmethod
def enterClassContext(cls, cm):
"""Same as enterContext, but class-wide."""
return _enter_context(cm, cls.addClassCleanup)
def setUp(self):
"Hook method for setting up the test fixture before exercising it."
pass
def tearDown(self):
"Hook method for deconstructing the test fixture after testing it."
pass
@classmethod
def setUpClass(cls):
"Hook method for setting up class fixture before running tests in the class."
@classmethod
def tearDownClass(cls):
"Hook method for deconstructing the class fixture after running all tests in the class."
def countTestCases(self):
return 1
def defaultTestResult(self):
return result.TestResult()
def shortDescription(self):
"""Returns a one-line description of the test, or None if no
description has been provided.
The default implementation of this method returns the first line of
the specified test method's docstring.
"""
doc = self._testMethodDoc
return doc.strip().split("\n")[0].strip() if doc else None
def id(self):
return "%s.%s" % (strclass(self.__class__), self._testMethodName)
def __eq__(self, other):
if type(self) is not type(other):
return NotImplemented
return self._testMethodName == other._testMethodName
def __hash__(self):
return hash((type(self), self._testMethodName))
def __str__(self):
return "%s (%s.%s)" % (self._testMethodName, strclass(self.__class__), self._testMethodName)
def __repr__(self):
return "<%s testMethod=%s>" % \
(strclass(self.__class__), self._testMethodName)
@contextlib.contextmanager
def subTest(self, msg=_subtest_msg_sentinel, **params):
"""Return a context manager that will return the enclosed block
of code in a subtest identified by the optional message and
keyword parameters. A failure in the subtest marks the test
case as failed but resumes execution at the end of the enclosed
block, allowing further test code to be executed.
"""
if self._outcome is None or not self._outcome.result_supports_subtests:
yield
return
parent = self._subtest
if parent is None:
params_map = _OrderedChainMap(params)
else:
params_map = parent.params.new_child(params)
self._subtest = _SubTest(self, msg, params_map)
try:
with self._outcome.testPartExecutor(self._subtest, subTest=True):
yield
if not self._outcome.success:
result = self._outcome.result
if result is not None and result.failfast:
raise _ShouldStop
elif self._outcome.expectedFailure:
# If the test is expecting a failure, we really want to
# stop now and register the expected failure.
raise _ShouldStop
finally:
self._subtest = parent
def _addExpectedFailure(self, result, exc_info):
try:
addExpectedFailure = result.addExpectedFailure
except AttributeError:
warnings.warn("TestResult has no addExpectedFailure method, reporting as passes",
RuntimeWarning)
result.addSuccess(self)
else:
addExpectedFailure(self, exc_info)
def _addUnexpectedSuccess(self, result):
try:
addUnexpectedSuccess = result.addUnexpectedSuccess
except AttributeError:
warnings.warn("TestResult has no addUnexpectedSuccess method, reporting as failure",
RuntimeWarning)
# We need to pass an actual exception and traceback to addFailure,
# otherwise the legacy result can choke.
try:
raise _UnexpectedSuccess from None
except _UnexpectedSuccess:
result.addFailure(self, sys.exc_info())
else:
addUnexpectedSuccess(self)
def _callSetUp(self):
self.setUp()
def _callTestMethod(self, method):
if method() is not None:
warnings.warn(f'It is deprecated to return a value!=None from a '
f'test case ({method})', DeprecationWarning, stacklevel=3)
def _callTearDown(self):
self.tearDown()
def _callCleanup(self, function, /, *args, **kwargs):
function(*args, **kwargs)
def run(self, result=None):
if result is None:
result = self.defaultTestResult()
startTestRun = getattr(result, 'startTestRun', None)
stopTestRun = getattr(result, 'stopTestRun', None)
if startTestRun is not None:
startTestRun()
else:
stopTestRun = None
result.startTest(self)
try:
testMethod = getattr(self, self._testMethodName)
if (getattr(self.__class__, "__unittest_skip__", False) or
getattr(testMethod, "__unittest_skip__", False)):
# If the class or method was skipped.
skip_why = (getattr(self.__class__, '__unittest_skip_why__', '')
or getattr(testMethod, '__unittest_skip_why__', ''))
_addSkip(result, self, skip_why)
return result
expecting_failure = (
getattr(self, "__unittest_expecting_failure__", False) or
getattr(testMethod, "__unittest_expecting_failure__", False)
)
outcome = _Outcome(result)
try:
self._outcome = outcome
with outcome.testPartExecutor(self):
self._callSetUp()
if outcome.success:
outcome.expecting_failure = expecting_failure
with outcome.testPartExecutor(self):
self._callTestMethod(testMethod)
outcome.expecting_failure = False
with outcome.testPartExecutor(self):
self._callTearDown()
self.doCleanups()
if outcome.success:
if expecting_failure:
if outcome.expectedFailure:
self._addExpectedFailure(result, outcome.expectedFailure)
else:
self._addUnexpectedSuccess(result)
else:
result.addSuccess(self)
return result
finally:
# explicitly break reference cycle:
# outcome.expectedFailure -> frame -> outcome -> outcome.expectedFailure
outcome.expectedFailure = None
outcome = None
# clear the outcome, no more needed
self._outcome = None
finally:
result.stopTest(self)
if stopTestRun is not None:
stopTestRun()
def doCleanups(self):
"""Execute all cleanup functions. Normally called for you after
tearDown."""
outcome = self._outcome or _Outcome()
while self._cleanups:
function, args, kwargs = self._cleanups.pop()
with outcome.testPartExecutor(self):
self._callCleanup(function, *args, **kwargs)
# return this for backwards compatibility
# even though we no longer use it internally
return outcome.success
@classmethod
def doClassCleanups(cls):
"""Execute all class cleanup functions. Normally called for you after
tearDownClass."""
cls.tearDown_exceptions = []
while cls._class_cleanups:
function, args, kwargs = cls._class_cleanups.pop()
try:
function(*args, **kwargs)
except Exception:
cls.tearDown_exceptions.append(sys.exc_info())
def __call__(self, *args, **kwds):
return self.run(*args, **kwds)
def debug(self):
"""Run the test without collecting errors in a TestResult"""
testMethod = getattr(self, self._testMethodName)
if (getattr(self.__class__, "__unittest_skip__", False) or
getattr(testMethod, "__unittest_skip__", False)):
# If the class or method was skipped.
skip_why = (getattr(self.__class__, '__unittest_skip_why__', '')
or getattr(testMethod, '__unittest_skip_why__', ''))
raise SkipTest(skip_why)
self._callSetUp()
self._callTestMethod(testMethod)
self._callTearDown()
while self._cleanups:
function, args, kwargs = self._cleanups.pop()
self._callCleanup(function, *args, **kwargs)
def skipTest(self, reason):
"""Skip this test."""
raise SkipTest(reason)
def fail(self, msg=None):
"""Fail immediately, with the given message."""
raise self.failureException(msg)
def assertFalse(self, expr, msg=None):
"""Check that the expression is false."""
if expr:
msg = self._formatMessage(msg, "%s is not false" % safe_repr(expr))
raise self.failureException(msg)
def assertTrue(self, expr, msg=None):
"""Check that the expression is true."""
if not expr:
msg = self._formatMessage(msg, "%s is not true" % safe_repr(expr))
raise self.failureException(msg)
def _formatMessage(self, msg, standardMsg):
"""Honour the longMessage attribute when generating failure messages.
If longMessage is False this means:
* Use only an explicit message if it is provided
* Otherwise use the standard message for the assert
If longMessage is True:
* Use the standard message
* If an explicit message is provided, plus ' : ' and the explicit message
"""
if not self.longMessage:
return msg or standardMsg
if msg is None:
return standardMsg
try:
# don't switch to '{}' formatting in Python 2.X
# it changes the way unicode input is handled
return '%s : %s' % (standardMsg, msg)
except UnicodeDecodeError:
return '%s : %s' % (safe_repr(standardMsg), safe_repr(msg))
def assertRaises(self, expected_exception, *args, **kwargs):
"""Fail unless an exception of class expected_exception is raised
by the callable when invoked with specified positional and
keyword arguments. If a different type of exception is
raised, it will not be caught, and the test case will be
deemed to have suffered an error, exactly as for an
unexpected exception.
If called with the callable and arguments omitted, will return a
context object used like this::
with self.assertRaises(SomeException):
do_something()
An optional keyword argument 'msg' can be provided when assertRaises
is used as a context object.
The context manager keeps a reference to the exception as
the 'exception' attribute. This allows you to inspect the
exception after the assertion::
with self.assertRaises(SomeException) as cm:
do_something()
the_exception = cm.exception
self.assertEqual(the_exception.error_code, 3)
"""
context = _AssertRaisesContext(expected_exception, self)
try:
return context.handle('assertRaises', args, kwargs)
finally:
# bpo-23890: manually break a reference cycle
context = None
def assertWarns(self, expected_warning, *args, **kwargs):
"""Fail unless a warning of class warnClass is triggered
by the callable when invoked with specified positional and
keyword arguments. If a different type of warning is
triggered, it will not be handled: depending on the other
warning filtering rules in effect, it might be silenced, printed
out, or raised as an exception.
If called with the callable and arguments omitted, will return a
context object used like this::
with self.assertWarns(SomeWarning):
do_something()
An optional keyword argument 'msg' can be provided when assertWarns
is used as a context object.
The context manager keeps a reference to the first matching
warning as the 'warning' attribute; similarly, the 'filename'
and 'lineno' attributes give you information about the line
of Python code from which the warning was triggered.
This allows you to inspect the warning after the assertion::
with self.assertWarns(SomeWarning) as cm:
do_something()
the_warning = cm.warning
self.assertEqual(the_warning.some_attribute, 147)
"""
context = _AssertWarnsContext(expected_warning, self)
return context.handle('assertWarns', args, kwargs)
def assertLogs(self, logger=None, level=None):
"""Fail unless a log message of level *level* or higher is emitted
on *logger_name* or its children. If omitted, *level* defaults to
INFO and *logger* defaults to the root logger.
This method must be used as a context manager, and will yield
a recording object with two attributes: `output` and `records`.
At the end of the context manager, the `output` attribute will
be a list of the matching formatted log messages and the
`records` attribute will be a list of the corresponding LogRecord
objects.
Example::
with self.assertLogs('foo', level='INFO') as cm:
logging.getLogger('foo').info('first message')
logging.getLogger('foo.bar').error('second message')
self.assertEqual(cm.output, ['INFO:foo:first message',
'ERROR:foo.bar:second message'])
"""
# Lazy import to avoid importing logging if it is not needed.
from ._log import _AssertLogsContext
return _AssertLogsContext(self, logger, level, no_logs=False)
def assertNoLogs(self, logger=None, level=None):
""" Fail unless no log messages of level *level* or higher are emitted
on *logger_name* or its children.
This method must be used as a context manager.
"""
from ._log import _AssertLogsContext
return _AssertLogsContext(self, logger, level, no_logs=True)
def _getAssertEqualityFunc(self, first, second):
"""Get a detailed comparison function for the types of the two args.
Returns: A callable accepting (first, second, msg=None) that will
raise a failure exception if first != second with a useful human
readable error message for those types.
"""
#
# NOTE(gregory.p.smith): I considered isinstance(first, type(second))
# and vice versa. I opted for the conservative approach in case
# subclasses are not intended to be compared in detail to their super
# class instances using a type equality func. This means testing
# subtypes won't automagically use the detailed comparison. Callers
# should use their type specific assertSpamEqual method to compare
# subclasses if the detailed comparison is desired and appropriate.
# See the discussion in http://bugs.python.org/issue2578.
#
if type(first) is type(second):
asserter = self._type_equality_funcs.get(type(first))
if asserter is not None:
if isinstance(asserter, str):
asserter = getattr(self, asserter)
return asserter
return self._baseAssertEqual
def _baseAssertEqual(self, first, second, msg=None):
"""The default assertEqual implementation, not type specific."""
if not first == second:
standardMsg = '%s != %s' % _common_shorten_repr(first, second)
msg = self._formatMessage(msg, standardMsg)
raise self.failureException(msg)
def assertEqual(self, first, second, msg=None):
"""Fail if the two objects are unequal as determined by the '=='
operator.
"""
assertion_func = self._getAssertEqualityFunc(first, second)
assertion_func(first, second, msg=msg)
def assertNotEqual(self, first, second, msg=None):
"""Fail if the two objects are equal as determined by the '!='
operator.
"""
if not first != second:
msg = self._formatMessage(msg, '%s == %s' % (safe_repr(first),
safe_repr(second)))
raise self.failureException(msg)
def assertAlmostEqual(self, first, second, places=None, msg=None,
delta=None):
"""Fail if the two objects are unequal as determined by their
difference rounded to the given number of decimal places
(default 7) and comparing to zero, or by comparing that the
difference between the two objects is more than the given
delta.
Note that decimal places (from zero) are usually not the same
as significant digits (measured from the most significant digit).
If the two objects compare equal then they will automatically
compare almost equal.
"""
if first == second:
# shortcut
return
if delta is not None and places is not None:
raise TypeError("specify delta or places not both")
diff = abs(first - second)
if delta is not None:
if diff <= delta:
return
standardMsg = '%s != %s within %s delta (%s difference)' % (
safe_repr(first),
safe_repr(second),
safe_repr(delta),
safe_repr(diff))
else:
if places is None:
places = 7
if round(diff, places) == 0:
return
standardMsg = '%s != %s within %r places (%s difference)' % (
safe_repr(first),
safe_repr(second),
places,
safe_repr(diff))
msg = self._formatMessage(msg, standardMsg)
raise self.failureException(msg)
def assertNotAlmostEqual(self, first, second, places=None, msg=None,
delta=None):
"""Fail if the two objects are equal as determined by their
difference rounded to the given number of decimal places
(default 7) and comparing to zero, or by comparing that the
difference between the two objects is less than the given delta.
Note that decimal places (from zero) are usually not the same
as significant digits (measured from the most significant digit).
Objects that are equal automatically fail.
"""
if delta is not None and places is not None:
raise TypeError("specify delta or places not both")
diff = abs(first - second)
if delta is not None:
if not (first == second) and diff > delta:
return
standardMsg = '%s == %s within %s delta (%s difference)' % (
safe_repr(first),
safe_repr(second),
safe_repr(delta),
safe_repr(diff))
else:
if places is None:
places = 7
if not (first == second) and round(diff, places) != 0:
return
standardMsg = '%s == %s within %r places' % (safe_repr(first),
safe_repr(second),
places)
msg = self._formatMessage(msg, standardMsg)
raise self.failureException(msg)
def assertSequenceEqual(self, seq1, seq2, msg=None, seq_type=None):
"""An equality assertion for ordered sequences (like lists and tuples).
For the purposes of this function, a valid ordered sequence type is one
which can be indexed, has a length, and has an equality operator.
Args:
seq1: The first sequence to compare.
seq2: The second sequence to compare.
seq_type: The expected datatype of the sequences, or None if no
datatype should be enforced.
msg: Optional message to use on failure instead of a list of
differences.
"""
if seq_type is not None:
seq_type_name = seq_type.__name__
if not isinstance(seq1, seq_type):
raise self.failureException('First sequence is not a %s: %s'
% (seq_type_name, safe_repr(seq1)))
if not isinstance(seq2, seq_type):
raise self.failureException('Second sequence is not a %s: %s'
% (seq_type_name, safe_repr(seq2)))
else:
seq_type_name = "sequence"
differing = None
try:
len1 = len(seq1)
except (TypeError, NotImplementedError):
differing = 'First %s has no length. Non-sequence?' % (
seq_type_name)
if differing is None:
try:
len2 = len(seq2)
except (TypeError, NotImplementedError):
differing = 'Second %s has no length. Non-sequence?' % (
seq_type_name)
if differing is None:
if seq1 == seq2:
return
differing = '%ss differ: %s != %s\n' % (
(seq_type_name.capitalize(),) +
_common_shorten_repr(seq1, seq2))
for i in range(min(len1, len2)):
try:
item1 = seq1[i]
except (TypeError, IndexError, NotImplementedError):
differing += ('\nUnable to index element %d of first %s\n' %
(i, seq_type_name))
break
try:
item2 = seq2[i]
except (TypeError, IndexError, NotImplementedError):
differing += ('\nUnable to index element %d of second %s\n' %
(i, seq_type_name))
break
if item1 != item2:
differing += ('\nFirst differing element %d:\n%s\n%s\n' %
((i,) + _common_shorten_repr(item1, item2)))
break
else:
if (len1 == len2 and seq_type is None and
type(seq1) != type(seq2)):
# The sequences are the same, but have differing types.
return
if len1 > len2:
differing += ('\nFirst %s contains %d additional '
'elements.\n' % (seq_type_name, len1 - len2))
try:
differing += ('First extra element %d:\n%s\n' %
(len2, safe_repr(seq1[len2])))
except (TypeError, IndexError, NotImplementedError):
differing += ('Unable to index element %d '
'of first %s\n' % (len2, seq_type_name))
elif len1 < len2:
differing += ('\nSecond %s contains %d additional '
'elements.\n' % (seq_type_name, len2 - len1))
try:
differing += ('First extra element %d:\n%s\n' %
(len1, safe_repr(seq2[len1])))
except (TypeError, IndexError, NotImplementedError):
differing += ('Unable to index element %d '
'of second %s\n' % (len1, seq_type_name))
standardMsg = differing
diffMsg = '\n' + '\n'.join(
difflib.ndiff(pprint.pformat(seq1).splitlines(),
pprint.pformat(seq2).splitlines()))
standardMsg = self._truncateMessage(standardMsg, diffMsg)
msg = self._formatMessage(msg, standardMsg)
self.fail(msg)
def _truncateMessage(self, message, diff):
max_diff = self.maxDiff
if max_diff is None or len(diff) <= max_diff:
return message + diff
return message + (DIFF_OMITTED % len(diff))
def assertListEqual(self, list1, list2, msg=None):
"""A list-specific equality assertion.
Args:
list1: The first list to compare.
list2: The second list to compare.
msg: Optional message to use on failure instead of a list of
differences.
"""
self.assertSequenceEqual(list1, list2, msg, seq_type=list)
def assertTupleEqual(self, tuple1, tuple2, msg=None):
"""A tuple-specific equality assertion.
Args:
tuple1: The first tuple to compare.
tuple2: The second tuple to compare.
msg: Optional message to use on failure instead of a list of
differences.
"""
self.assertSequenceEqual(tuple1, tuple2, msg, seq_type=tuple)
def assertSetEqual(self, set1, set2, msg=None):
"""A set-specific equality assertion.
Args:
set1: The first set to compare.
set2: The second set to compare.
msg: Optional message to use on failure instead of a list of
differences.
assertSetEqual uses ducktyping to support different types of sets, and
is optimized for sets specifically (parameters must support a
difference method).
"""
try:
difference1 = set1.difference(set2)
except TypeError as e:
self.fail('invalid type when attempting set difference: %s' % e)
except AttributeError as e:
self.fail('first argument does not support set difference: %s' % e)
try:
difference2 = set2.difference(set1)
except TypeError as e:
self.fail('invalid type when attempting set difference: %s' % e)
except AttributeError as e:
self.fail('second argument does not support set difference: %s' % e)
if not (difference1 or difference2):
return
lines = []
if difference1:
lines.append('Items in the first set but not the second:')
for item in difference1:
lines.append(repr(item))
if difference2:
lines.append('Items in the second set but not the first:')
for item in difference2:
lines.append(repr(item))
standardMsg = '\n'.join(lines)
self.fail(self._formatMessage(msg, standardMsg))
def assertIn(self, member, container, msg=None):
"""Just like self.assertTrue(a in b), but with a nicer default message."""
if member not in container:
standardMsg = '%s not found in %s' % (safe_repr(member),
safe_repr(container))
self.fail(self._formatMessage(msg, standardMsg))
def assertNotIn(self, member, container, msg=None):
"""Just like self.assertTrue(a not in b), but with a nicer default message."""
if member in container:
standardMsg = '%s unexpectedly found in %s' % (safe_repr(member),
safe_repr(container))
self.fail(self._formatMessage(msg, standardMsg))
def assertIs(self, expr1, expr2, msg=None):
"""Just like self.assertTrue(a is b), but with a nicer default message."""
if expr1 is not expr2:
standardMsg = '%s is not %s' % (safe_repr(expr1),
safe_repr(expr2))
self.fail(self._formatMessage(msg, standardMsg))
def assertIsNot(self, expr1, expr2, msg=None):
"""Just like self.assertTrue(a is not b), but with a nicer default message."""
if expr1 is expr2:
standardMsg = 'unexpectedly identical: %s' % (safe_repr(expr1),)
self.fail(self._formatMessage(msg, standardMsg))
def assertDictEqual(self, d1, d2, msg=None):
self.assertIsInstance(d1, dict, 'First argument is not a dictionary')
self.assertIsInstance(d2, dict, 'Second argument is not a dictionary')
if d1 != d2:
standardMsg = '%s != %s' % _common_shorten_repr(d1, d2)
diff = ('\n' + '\n'.join(difflib.ndiff(
pprint.pformat(d1).splitlines(),
pprint.pformat(d2).splitlines())))
standardMsg = self._truncateMessage(standardMsg, diff)
self.fail(self._formatMessage(msg, standardMsg))
def assertDictContainsSubset(self, subset, dictionary, msg=None):
"""Checks whether dictionary is a superset of subset."""
warnings.warn('assertDictContainsSubset is deprecated',
DeprecationWarning)
missing = []
mismatched = []
for key, value in subset.items():
if key not in dictionary:
missing.append(key)
elif value != dictionary[key]:
mismatched.append('%s, expected: %s, actual: %s' %
(safe_repr(key), safe_repr(value),
safe_repr(dictionary[key])))
if not (missing or mismatched):
return
standardMsg = ''
if missing:
standardMsg = 'Missing: %s' % ','.join(safe_repr(m) for m in
missing)
if mismatched:
if standardMsg:
standardMsg += '; '
standardMsg += 'Mismatched values: %s' % ','.join(mismatched)
self.fail(self._formatMessage(msg, standardMsg))
def assertCountEqual(self, first, second, msg=None):
"""Asserts that two iterables have the same elements, the same number of
times, without regard to order.
self.assertEqual(Counter(list(first)),
Counter(list(second)))
Example:
- [0, 1, 1] and [1, 0, 1] compare equal.
- [0, 0, 1] and [0, 1] compare unequal.
"""
first_seq, second_seq = list(first), list(second)
try:
first = collections.Counter(first_seq)
second = collections.Counter(second_seq)
except TypeError:
# Handle case with unhashable elements
differences = _count_diff_all_purpose(first_seq, second_seq)
else:
if first == second:
return
differences = _count_diff_hashable(first_seq, second_seq)
if differences:
standardMsg = 'Element counts were not equal:\n'
lines = ['First has %d, Second has %d: %r' % diff for diff in differences]
diffMsg = '\n'.join(lines)
standardMsg = self._truncateMessage(standardMsg, diffMsg)
msg = self._formatMessage(msg, standardMsg)
self.fail(msg)
def assertMultiLineEqual(self, first, second, msg=None):
"""Assert that two multi-line strings are equal."""
self.assertIsInstance(first, str, 'First argument is not a string')
self.assertIsInstance(second, str, 'Second argument is not a string')
if first != second:
# don't use difflib if the strings are too long
if (len(first) > self._diffThreshold or
len(second) > self._diffThreshold):
self._baseAssertEqual(first, second, msg)
firstlines = first.splitlines(keepends=True)
secondlines = second.splitlines(keepends=True)
if len(firstlines) == 1 and first.strip('\r\n') == first:
firstlines = [first + '\n']
secondlines = [second + '\n']
standardMsg = '%s != %s' % _common_shorten_repr(first, second)
diff = '\n' + ''.join(difflib.ndiff(firstlines, secondlines))
standardMsg = self._truncateMessage(standardMsg, diff)
self.fail(self._formatMessage(msg, standardMsg))
def assertLess(self, a, b, msg=None):
"""Just like self.assertTrue(a < b), but with a nicer default message."""
if not a < b:
standardMsg = '%s not less than %s' % (safe_repr(a), safe_repr(b))
self.fail(self._formatMessage(msg, standardMsg))
def assertLessEqual(self, a, b, msg=None):
"""Just like self.assertTrue(a <= b), but with a nicer default message."""
if not a <= b:
standardMsg = '%s not less than or equal to %s' % (safe_repr(a), safe_repr(b))
self.fail(self._formatMessage(msg, standardMsg))
def assertGreater(self, a, b, msg=None):
"""Just like self.assertTrue(a > b), but with a nicer default message."""
if not a > b:
standardMsg = '%s not greater than %s' % (safe_repr(a), safe_repr(b))
self.fail(self._formatMessage(msg, standardMsg))
def assertGreaterEqual(self, a, b, msg=None):
"""Just like self.assertTrue(a >= b), but with a nicer default message."""
if not a >= b:
standardMsg = '%s not greater than or equal to %s' % (safe_repr(a), safe_repr(b))
self.fail(self._formatMessage(msg, standardMsg))
def assertIsNone(self, obj, msg=None):
"""Same as self.assertTrue(obj is None), with a nicer default message."""
if obj is not None:
standardMsg = '%s is not None' % (safe_repr(obj),)
self.fail(self._formatMessage(msg, standardMsg))
def assertIsNotNone(self, obj, msg=None):
"""Included for symmetry with assertIsNone."""
if obj is None:
standardMsg = 'unexpectedly None'
self.fail(self._formatMessage(msg, standardMsg))
def assertIsInstance(self, obj, cls, msg=None):
"""Same as self.assertTrue(isinstance(obj, cls)), with a nicer
default message."""
if not isinstance(obj, cls):
standardMsg = '%s is not an instance of %r' % (safe_repr(obj), cls)
self.fail(self._formatMessage(msg, standardMsg))
def assertNotIsInstance(self, obj, cls, msg=None):
"""Included for symmetry with assertIsInstance."""
if isinstance(obj, cls):
standardMsg = '%s is an instance of %r' % (safe_repr(obj), cls)
self.fail(self._formatMessage(msg, standardMsg))
def assertRaisesRegex(self, expected_exception, expected_regex,
*args, **kwargs):
"""Asserts that the message in a raised exception matches a regex.
Args:
expected_exception: Exception class expected to be raised.
expected_regex: Regex (re.Pattern object or string) expected
to be found in error message.
args: Function to be called and extra positional args.
kwargs: Extra kwargs.
msg: Optional message used in case of failure. Can only be used
when assertRaisesRegex is used as a context manager.
"""
context = _AssertRaisesContext(expected_exception, self, expected_regex)
return context.handle('assertRaisesRegex', args, kwargs)
def assertWarnsRegex(self, expected_warning, expected_regex,
*args, **kwargs):
"""Asserts that the message in a triggered warning matches a regexp.
Basic functioning is similar to assertWarns() with the addition
that only warnings whose messages also match the regular expression
are considered successful matches.
Args:
expected_warning: Warning class expected to be triggered.
expected_regex: Regex (re.Pattern object or string) expected
to be found in error message.
args: Function to be called and extra positional args.
kwargs: Extra kwargs.
msg: Optional message used in case of failure. Can only be used
when assertWarnsRegex is used as a context manager.
"""
context = _AssertWarnsContext(expected_warning, self, expected_regex)
return context.handle('assertWarnsRegex', args, kwargs)
def assertRegex(self, text, expected_regex, msg=None):
"""Fail the test unless the text matches the regular expression."""
if isinstance(expected_regex, (str, bytes)):
assert expected_regex, "expected_regex must not be empty."
expected_regex = re.compile(expected_regex)
if not expected_regex.search(text):
standardMsg = "Regex didn't match: %r not found in %r" % (
expected_regex.pattern, text)
# _formatMessage ensures the longMessage option is respected
msg = self._formatMessage(msg, standardMsg)
raise self.failureException(msg)
def assertNotRegex(self, text, unexpected_regex, msg=None):
"""Fail the test if the text matches the regular expression."""
if isinstance(unexpected_regex, (str, bytes)):
unexpected_regex = re.compile(unexpected_regex)
match = unexpected_regex.search(text)
if match:
standardMsg = 'Regex matched: %r matches %r in %r' % (
text[match.start() : match.end()],
unexpected_regex.pattern,
text)
# _formatMessage ensures the longMessage option is respected
msg = self._formatMessage(msg, standardMsg)
raise self.failureException(msg)
def _deprecate(original_func):
def deprecated_func(*args, **kwargs):
warnings.warn(
'Please use {0} instead.'.format(original_func.__name__),
DeprecationWarning, 2)
return original_func(*args, **kwargs)
return deprecated_func
# see #9424
failUnlessEqual = assertEquals = _deprecate(assertEqual)
failIfEqual = assertNotEquals = _deprecate(assertNotEqual)
failUnlessAlmostEqual = assertAlmostEquals = _deprecate(assertAlmostEqual)
failIfAlmostEqual = assertNotAlmostEquals = _deprecate(assertNotAlmostEqual)
failUnless = assert_ = _deprecate(assertTrue)
failUnlessRaises = _deprecate(assertRaises)
failIf = _deprecate(assertFalse)
assertRaisesRegexp = _deprecate(assertRaisesRegex)
assertRegexpMatches = _deprecate(assertRegex)
assertNotRegexpMatches = _deprecate(assertNotRegex)
class FunctionTestCase(TestCase):
"""A test case that wraps a test function.
This is useful for slipping pre-existing test functions into the
unittest framework. Optionally, set-up and tidy-up functions can be
supplied. As with TestCase, the tidy-up ('tearDown') function will
always be called if the set-up ('setUp') function ran successfully.
"""
def __init__(self, testFunc, setUp=None, tearDown=None, description=None):
super(FunctionTestCase, self).__init__()
self._setUpFunc = setUp
self._tearDownFunc = tearDown
self._testFunc = testFunc
self._description = description
def setUp(self):
if self._setUpFunc is not None:
self._setUpFunc()
def tearDown(self):
if self._tearDownFunc is not None:
self._tearDownFunc()
def runTest(self):
self._testFunc()
def id(self):
return self._testFunc.__name__
def __eq__(self, other):
if not isinstance(other, self.__class__):
return NotImplemented
return self._setUpFunc == other._setUpFunc and \
self._tearDownFunc == other._tearDownFunc and \
self._testFunc == other._testFunc and \
self._description == other._description
def __hash__(self):
return hash((type(self), self._setUpFunc, self._tearDownFunc,
self._testFunc, self._description))
def __str__(self):
return "%s (%s)" % (strclass(self.__class__),
self._testFunc.__name__)
def __repr__(self):
return "<%s tec=%s>" % (strclass(self.__class__),
self._testFunc)
def shortDescription(self):
if self._description is not None:
return self._description
doc = self._testFunc.__doc__
return doc and doc.split("\n")[0].strip() or None
class _SubTest(TestCase):
def __init__(self, test_case, message, params):
super().__init__()
self._message = message
self.test_case = test_case
self.params = params
self.failureException = test_case.failureException
def runTest(self):
raise NotImplementedError("subtests cannot be run directly")
def _subDescription(self):
parts = []
if self._message is not _subtest_msg_sentinel:
parts.append("[{}]".format(self._message))
if self.params:
params_desc = ', '.join(
"{}={!r}".format(k, v)
for (k, v) in self.params.items())
parts.append("({})".format(params_desc))
return " ".join(parts) or '(<subtest>)'
def id(self):
return "{} {}".format(self.test_case.id(), self._subDescription())
def shortDescription(self):
"""Returns a one-line description of the subtest, or None if no
description has been provided.
"""
return self.test_case.shortDescription()
def __str__(self):
return "{} {}".format(self.test_case, self._subDescription())