Function check_function

pythonwhat/checks/check_function.py:39–172

Check whether a particular function is called. ``check_function()`` is typically followed by: - ``check_args()`` to check whether the arguments were specified. In turn, ``check_args()`` can be followed by ``has_equal_value()`` or ``has_equal_ast()`` to assert that the arguments

(
    state,
    name,
    index=0,
    missing_msg=None,
    params_not_matched_msg=None,
    expand_msg=None,
    signature=True,
)

def check_function(
    state,
    name,
    index=0,
    missing_msg=None,
    params_not_matched_msg=None,
    expand_msg=None,
    signature=True,
):
    """Check whether a particular function is called.

    ``check_function()`` is typically followed by:

    - ``check_args()`` to check whether the arguments were specified.
      In turn, ``check_args()`` can be followed by ``has_equal_value()`` or ``has_equal_ast()``
      to assert that the arguments were correctly specified.
    - ``has_equal_value()`` to check whether rerunning the function call coded by the student
      gives the same result as calling the function call as in the solution.

    Checking function calls is a tricky topic. Please visit the
    `dedicated article <articles/checking_function_calls.html>`_ for more explanation,
    edge cases and best practices.

    Args:
        name (str): the name of the function to be tested. When checking functions in packages, always
            use the 'full path' of the function.
        index (int): index of the function call to be checked. Defaults to 0.
        missing_msg (str): If specified, this overrides an automatically generated feedback message in case
            the student did not call the function correctly.
        params_not_matched_msg (str): If specified, this overrides an automatically generated feedback message
            in case the function parameters were not successfully matched.
        expand_msg (str): If specified, this overrides any messages that are prepended by previous SCT chains.
        signature (Signature): Normally, check_function() can figure out what the function signature is,
            but it might be necessary to use ``sig_from_params()`` to manually build a signature and pass this along.
        state (State): State object that is passed from the SCT Chain (don&#x27;t specify this).

    :Examples:

        Student code and solution code::

            import numpy as np
            arr = np.array([1, 2, 3, 4, 5])
            np.mean(arr)

        SCT::

            # Verify whether arr was correctly set in np.mean
            Ex().check_function('numpy.mean').check_args('a').has_equal_value()

            # Verify whether np.mean(arr) produced the same result
            Ex().check_function('numpy.mean').has_equal_value()
    """

    append_missing = missing_msg is None
    append_params_not_matched = params_not_matched_msg is None
    if missing_msg is None:
        missing_msg = MISSING_MSG
    if expand_msg is None: