Mock Patches Appearing in the Wrong Order?

问题

I have a test module (test.py) which imports functions from another module (keyboard.py).

keyboard.py

def get_keys(keyList, timeStamped):
    return event.getKeys(keyList=keyList, timeStamped=timeStamped)

def wait_keys(keyList, timeStamped):
    return event.waitKeys(keyList=keyList, timeStamped=timeStamped)

test.py

@mock.patch('keyboard.wait_keys')
@mock.patch('keyboard.get_keys')
def test_2(self, mock_waitKeys, mock_getKeys):

    mock_waitKeys.return_value = [['wait_keys!', 0.1]]
    mock_getKeys.return_value = [['get_keys!',0.1]]

    run_blocks(trials,noise,win,expInfo, incorrect, tone1, tone2, experiment_details,allPoints,32,60)            

I'm trying to put two mock return values in place but their effects are inversed.

When I call them in the interactive console while stopped at a breakpoint—or inspect the values when called normally—the two mocked functions return each other's fake return values. From the console:

get_keys()
Out[2]: [['wait_keys!', 0.1]]
wait_keys()
Out[3]: [['get_keys!', 0.1]]

Why are my mock patches appearing in the wrong order?

回答1:

The order of your patches should be reversed, as they are applied bottom up. See this comment in the python docs on nested mock arguments:

Note When you nest patch decorators the mocks are passed in to the decorated function in the same order they applied (the normal python order that decorators are applied). This means from the bottom up, so in the example above the mock for module.ClassName1 is passed in first.

来源：https://stackoverflow.com/questions/47042196/mock-patches-appearing-in-the-wrong-order