I would like to use pytest monkeypatch to mock a class which is imported into a separate module. Is this actually possible, and if so how does one do it? It seems like I have not seen an example for this exact situation. Suppose you have app with and imported class A in something.py from something import A #Class is imported class B : def __init__(self) : self.instance = A() #class instance is created def f(self, value) : return self.instance.g(value) inside my test.py I want to mock A inside B from something import B #this is where I would mock A such that def mock_A : def g(self, value) : return 2*value #Then I would call B c = B() print(c.g(2)) #would be 4 I see how monkeypatch can be used to patch instances of classes, but how is it done for classes that have not yet been instantiated? Is it possible? Thanks! Continue reading...
