Invalid setattr() call

Detects invalid usage of setattr() built-in function, which bypasses type checking and can lead to runtime type errors.

setattr() allows dynamic attribute assignment, letting you assign any type to any attribute regardless of type annotations. Type checkers can't track these dynamic modifications.

What gets flagged

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class Foo:
    def __init__(self) -> None:
        self.x: str = "hello"

foo = Foo()
setattr(foo, "x", 1)

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error[invalid-setattr]: Using `setattr()` bypasses type checking and can lead to runtime type errors.
 --> main.py:6:1
  |
5 | foo = Foo()
6 | setattr(foo, "x", 1)
  | ^^^^^^^^^^^^^^^^^^^^
  |
info: Object of type Literal[1] is not assignable to type str
info: rule `invalid-setattr` was selected in the configuration file