micropython/tests/basics/class_use_other.py

# check that we can use an instance of B in a method of A

class A:
    def store(a, b):
        a.value = b

class B:
    pass

b = B()
A.store(b, 1)
print(b.value)
py: Use a wrapper to explicitly check self argument of builtin methods. Previous to this patch a call such as list.append(1, 2) would lead to a seg fault. This is because list.append is a builtin method and the first argument to such methods is always assumed to have the correct type. Now, when a builtin method is extracted like this it is wrapped in a checker object which checks the the type of the first argument before calling the builtin function. This feature is contrelled by MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG and is enabled by default. See issue #1216. 10 years ago			`# check that we can use an instance of B in a method of A`

			`class A:`
			`def store(a, b):`
			`a.value = b`

			`class B:`
			`pass`

			`b = B()`
			`A.store(b, 1)`
			`print(b.value)`