Find Out If a Function has been Called

Question

I am programming in Python, and I am wondering if i can test if a function has been called in my code

def example():     pass example() #Pseudocode: if example.has_been_called:    print("foo bar") 

How would I do this?

Answer 1

If it's OK for the function to know its own name, you can use a function attribute:

def example():     example.has_been_called = True     pass example.has_been_called = False   example()  #Actual Code!: if example.has_been_called:    print("foo bar") 

You could also use a decorator to set the attribute:

import functools  def trackcalls(func):     @functools.wraps(func)     def wrapper(*args, **kwargs):         wrapper.has_been_called = True         return func(*args, **kwargs)     wrapper.has_been_called = False     return wrapper  @trackcalls def example():     pass   example()  #Actual Code!: if example.has_been_called:    print("foo bar") 

Answer 2

We can use mock.Mock

from unittest import mock   def check_called(func):     return mock.Mock(side_effect=func)   @check_called def summator(a, b):     print(a + b)   summator(1, 3) summator.assert_called() assert summator.called == True assert summator.call_count > 0  summator.assert_called_with(1, 3)  summator.assert_called_with(1, 5)  # error # AssertionError: Expected call: mock(1, 5) # Actual call: mock(1, 3)