Bug Report

Python seems to treat raise ValueError the same way as raise ValueError(), with implicit instantiation, but Mypy doesn't seem to have the same behavior.

See: https://docs.python.org/3/tutorial/errors.html#raising-exceptions

To Reproduce

1. Define subclass of Exception where __init__ has mandatory arguments
2. raise SomeException

class SomeException(Exception):
    thing: str
    
    def __init__(self, thing: str) -> None:
        self.thing = thing

    def __str__(self) -> str:
        return f"There's a {self.thing} in my boot"
        
# BUG: Mypy does not see this problem.
def a() -> None:
    raise SomeException
    
# Correct: Mypy identifies the problem.
def b() -> None:
    raise SomeException()
    
# Correct: Mypy identifies that there is no problem here.
def c() -> None:
    raise SomeException(thing="snake")

https://mypy-play.net/?mypy=latest&python=3.10&gist=158348310d55f703fc05bacde65af438

Expected Behavior

This should throw an error about missing mandatory arguments.

Actual Behavior

No error.

Your Environment

• Mypy version used: 0.910
• Mypy command-line flags: None
• Mypy configuration options from mypy.ini (and other config files): None
• Python version used: 3.10
• Operating system and version: N/A