Translation failed during import of builtin python module with missing type annotations

[gewlar]

Nagini returns Type error: Encountered Any type. Type annotation missing? (dataclasses@14.0), when running the following snippet:

from nagini_contracts.contracts import *
from dataclasses import dataclass

class foo:
    pass

Checking the same file with mypy works without issue.

The same error with message Type error: Encountered Any type. Type annotation missing? (enum@25.0) occurs when importing the enum module:

from nagini_contracts.contracts import *
from enum import IntEnum

class foo(IntEnum):
    pass

[marcoeilers]

So when dealing with imports from the standard library, you essentially have two different options:

• Either you write custom stubs for the relevant parts of the library in the form of a .pyi file, put that on the MYPYPATH, and make sure that this file only contains things Nagini knows how to deal with. That's the way to go if you want to just use ordinary classes, functions etc. from the standard library.
• Or, if you want to use decorators or special classes that do things that aren't supported directly in Nagini, you have to modify Nagini to support them: 1. You put the name of the module in the IGNORED_IMPORTS list, and then 2. You implement support for the relevant constructs directly in Nagini's translators (so, for example, you implement support for dataclass-annotated classes the way Nagini currently has support for Pure-annotated functions).

[gewlar]

Added support for dataclasses in 2d819f3