mypy does not warn about incorrect default value in dict.get in some case

It seems that mypy should actually warn about the assignment of the set in the following code:

from typing import Dict, Any

params: Dict[str, Any] = {}
a: Dict[str, Any] = params.get("abc", set())
reveal_type(a)

mypy does not warn about the incorrect assignment of Set to a but correctly reveals that the type of a is Dict[str, Any]. Sadly the use of Any in this case is common as these dicts represent complex configuration files.

Tested with the current git master version.

Comienza con el ejemplo mínimo de Python del issue y ejecuta mypy para confirmar que no se informa del valor predeterminado incompatible set() para la asignación Dict[str, Any]. Rastrea el comportamiento de comprobación de tipos de dict.get y Any, y añade cobertura que muestre que este caso produce una advertencia mientras el tipo revelado sigue siendo adecuado.