Bug Report

mypy complaining that class annotated with @dataclass(slots=True) has no attribute __slots__

To Reproduce

from dataclasses import dataclass


class Point1:
    __slots__ = ('x', 'y')


@dataclass(slots=True)
class Point2:
    x: float
    y: float


print(Point1.__slots__)
print(Point2.__slots__)

Expected Behavior

No error should be produced

Actual Behavior

Running python test.py produces

('x', 'y')
('x', 'y')

Running mypy test.py produces

test.py:15: error: "type[Point2]" has no attribute "__slots__"  [attr-defined]
Found 1 error in 1 file (checked 1 source file)

Your Environment

• Mypy version used: 1.4.1
• Mypy command-line flags:
• Mypy configuration options from mypy.ini (and other config files):
• Python version used: 3.11.1