def seal()

in later/unittest/backport/mock.py [0:0]


def seal(mock):
    """Disable the automatic generation of child mocks.

    Given an input Mock, seals it to ensure no further mocks will be generated
    when accessing an attribute that was not already defined.

    The operation recursively seals the mock passed in, meaning that
    the mock itself, any mocks generated by accessing one of its attributes,
    and all assigned mocks without a name or spec will be sealed.
    """
    mock._mock_sealed = True
    for attr in dir(mock):
        try:
            m = getattr(mock, attr)
        except AttributeError:
            continue
        if not isinstance(m, NonCallableMock):
            continue
        if m._mock_new_parent is mock:
            seal(m)