Python Mocking with unitest.mock 2
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Internal
Mocking a Method
The general approach is to replace at runtime the real method instance associated with the class instance to be tested with a Mock
instance, configured to simulate various behaviors of the real method.
Assuming that our dependency to test with is SomeClass
, and this class has a some_method(nuance: str)
whose behavior we want to mock during testing, the initial implementation of the class and method could be:
class SomeClass:
def __init__(self, color: str):
self._color = color
def some_method(self, nuance: str) -> str:
return f'{nuance} {self._color}'.upper()
The normal behavior of the method some_method(nuance: str)
is reflected by:
c = SomeClass('blue')
assert c.some_method('dark') == 'DARK BLUE'
c._color = 'red'
assert c.some_method('light') == 'LIGHT RED'