assert_raises(exception_class, callable, *args, **kwargs) assert_raises(exception_class)[source]¶
Fail unless an exception of class exception_class is thrown by callable when invoked with arguments args and keyword arguments kwargs. If a different type of exception is thrown, it will not be caught, and the test case will be deemed to have suffered an error, exactly as for an unexpected exception.
assert_raisescan be used as a context manager:
>>> from numpy.testing import assert_raises >>> with assert_raises(ZeroDivisionError): ... 1 / 0
is equivalent to
>>> def div(x, y): ... return x / y >>> assert_raises(ZeroDivisionError, div, 1, 0)