"""py.test hacks to support XFAIL/XPASS""" from __future__ import print_function, division import sys import functools import os import contextlib import warnings from sympy.core.compatibility import get_function_name, string_types from sympy.utilities.exceptions import SymPyDeprecationWarning try: import py from _pytest.python_api import raises from _pytest.recwarn import warns from _pytest.outcomes import skip, Failed USE_PYTEST = getattr(sys, '_running_pytest', False) except ImportError: USE_PYTEST = False ON_TRAVIS = os.getenv('TRAVIS_BUILD_NUMBER', None) if not USE_PYTEST: def raises(expectedException, code=None): """ Tests that ``code`` raises the exception ``expectedException``. ``code`` may be a callable, such as a lambda expression or function name. If ``code`` is not given or None, ``raises`` will return a context manager for use in ``with`` statements; the code to execute then comes from the scope of the ``with``. ``raises()`` does nothing if the callable raises the expected exception, otherwise it raises an AssertionError. Examples ======== >>> from sympy.utilities.pytest import raises >>> raises(ZeroDivisionError, lambda: 1/0) >>> raises(ZeroDivisionError, lambda: 1/2) Traceback (most recent call last): ... Failed: DID NOT RAISE >>> with raises(ZeroDivisionError): ... n = 1/0 >>> with raises(ZeroDivisionError): ... n = 1/2 Traceback (most recent call last): ... Failed: DID NOT RAISE Note that you cannot test multiple statements via ``with raises``: >>> with raises(ZeroDivisionError): ... n = 1/0 # will execute and raise, aborting the ``with`` ... n = 9999/0 # never executed This is just what ``with`` is supposed to do: abort the contained statement sequence at the first exception and let the context manager deal with the exception. To test multiple statements, you'll need a separate ``with`` for each: >>> with raises(ZeroDivisionError): ... n = 1/0 # will execute and raise >>> with raises(ZeroDivisionError): ... n = 9999/0 # will also execute and raise """ if code is None: return RaisesContext(expectedException) elif callable(code): try: code() except expectedException: return raise Failed("DID NOT RAISE") elif isinstance(code, string_types): raise TypeError( '\'raises(xxx, "code")\' has been phased out; ' 'change \'raises(xxx, "expression")\' ' 'to \'raises(xxx, lambda: expression)\', ' '\'raises(xxx, "statement")\' ' 'to \'with raises(xxx): statement\'') else: raise TypeError( 'raises() expects a callable for the 2nd argument.') class RaisesContext(object): def __init__(self, expectedException): self.expectedException = expectedException def __enter__(self): return None def __exit__(self, exc_type, exc_value, traceback): if exc_type is None: raise Failed("DID NOT RAISE") return issubclass(exc_type, self.expectedException) class XFail(Exception): pass class XPass(Exception): pass class Skipped(Exception): pass class Failed(Exception): pass def XFAIL(func): def wrapper(): try: func() except Exception as e: message = str(e) if message != "Timeout": raise XFail(get_function_name(func)) else: raise Skipped("Timeout") raise XPass(get_function_name(func)) wrapper = functools.update_wrapper(wrapper, func) return wrapper def skip(str): raise Skipped(str) def SKIP(reason): """Similar to :func:`skip`, but this is a decorator. """ def wrapper(func): def func_wrapper(): raise Skipped(reason) func_wrapper = functools.update_wrapper(func_wrapper, func) return func_wrapper return wrapper def slow(func): func._slow = True def func_wrapper(): func() func_wrapper = functools.update_wrapper(func_wrapper, func) func_wrapper.__wrapped__ = func return func_wrapper @contextlib.contextmanager def warns(warningcls, **kwargs): '''Like raises but tests that warnings are emitted. >>> from sympy.utilities.pytest import warns >>> import warnings >>> with warns(UserWarning): ... warnings.warn('deprecated', UserWarning) >>> with warns(UserWarning): ... pass Traceback (most recent call last): ... Failed: DID NOT WARN. No warnings of type UserWarning\ was emitted. The list of emitted warnings is: []. ''' match = kwargs.pop('match', '') if kwargs: raise TypeError('Invalid keyword arguments: %s' % kwargs) # Absorbs all warnings in warnrec with warnings.catch_warnings(record=True) as warnrec: # Hide all warnings but make sure that our warning is emitted warnings.simplefilter("ignore") warnings.filterwarnings("always", match, warningcls) # Now run the test yield # Raise if expected warning not found if not any(issubclass(w.category, warningcls) for w in warnrec): msg = ('Failed: DID NOT WARN.' ' No warnings of type %s was emitted.' ' The list of emitted warnings is: %s.' ) % (warningcls, [w.message for w in warnrec]) raise Failed(msg) else: XFAIL = py.test.mark.xfail slow = py.test.mark.slow def SKIP(reason): def skipping(func): @functools.wraps(func) def inner(*args, **kwargs): skip(reason) return inner return skipping @contextlib.contextmanager def warns_deprecated_sympy(): '''Shorthand for ``warns(SymPyDeprecationWarning)`` This is the recommended way to test that ``SymPyDeprecationWarning`` is emitted for deprecated features in SymPy. To test for other warnings use ``warns``. To suppress warnings without asserting that they are emitted use ``ignore_warnings``. >>> from sympy.utilities.pytest import warns_deprecated_sympy >>> from sympy.utilities.exceptions import SymPyDeprecationWarning >>> import warnings >>> with warns_deprecated_sympy(): ... SymPyDeprecationWarning("Don't use", feature="old thing", ... deprecated_since_version="1.0", issue=123).warn() >>> with warns_deprecated_sympy(): ... pass Traceback (most recent call last): ... Failed: DID NOT WARN. No warnings of type \ SymPyDeprecationWarning was emitted. The list of emitted warnings is: []. ''' with warns(SymPyDeprecationWarning): yield @contextlib.contextmanager def ignore_warnings(warningcls): '''Context manager to suppress warnings during tests. This function is useful for suppressing warnings during tests. The warns function should be used to assert that a warning is raised. The ignore_warnings function is useful in situation when the warning is not guaranteed to be raised (e.g. on importing a module) or if the warning comes from third-party code. When the warning is coming (reliably) from SymPy the warns function should be preferred to ignore_warnings. >>> from sympy.utilities.pytest import ignore_warnings >>> import warnings Here's a warning: >>> with warnings.catch_warnings(): # reset warnings in doctest ... warnings.simplefilter('error') ... warnings.warn('deprecated', UserWarning) Traceback (most recent call last): ... UserWarning: deprecated Let's suppress it with ignore_warnings: >>> with warnings.catch_warnings(): # reset warnings in doctest ... warnings.simplefilter('error') ... with ignore_warnings(UserWarning): ... warnings.warn('deprecated', UserWarning) (No warning emitted) ''' # Absorbs all warnings in warnrec with warnings.catch_warnings(record=True) as warnrec: # Make sure our warning doesn't get filtered warnings.simplefilter("always", warningcls) # Now run the test yield # Reissue any warnings that we aren't testing for for w in warnrec: if not issubclass(w.category, warningcls): warnings.warn_explicit(w.message, w.category, w.filename, w.lineno)