Dataclass inheritance appears to be handled incorrectly

[bbarker]

• Are you reporting a bug, or opening a feature request?

Bug

• Please insert below the code you are checking with mypy,
  or a mock-up repro if the source is private. We would appreciate
  if you try to simplify your case to a minimal repro.

Code where the error occurs:

        self.primary_archive = Archive(  
            id=taxonomy.CATEGORIES[self.primary_category.id]['in_archive'])
        self.primary_group = Group( 
            id=taxonomy.ARCHIVES[self.primary_archive.id]['in_group'])

dataclass defs:

@dataclass
class Category():
    """Represents an arXiv category."""

    id: str = field(default_factory=str)
    """The category identifier (e.g. cs.DL)."""
    name: str = field(init=False)
    """The name of the category (e.g. Digital Libraries)."""

    def __post_init__(self) -> None:
        """Get the full category name."""
        if self.id in taxonomy.CATEGORIES:
            self.name = taxonomy.CATEGORIES[self.id]['name']


@dataclass
class Archive(Category):
    """Represents an arXiv archive."""

    def __post_init__(self) -> None:
        """Get the full archive name."""
        if self.id in taxonomy.ARCHIVES:
            self.name = taxonomy.ARCHIVES[self.id]['name']

• What is the actual behavior/output?

I get a Unexpected keyword argument for id when trying to create instances of Abstract.

• What is the behavior/output you expect?

No type errors.

• What are the versions of mypy and Python you are using?

I haven't tried git master:

python = 3.6.6
mypy = 0.620

• What are the mypy flags you are using? (For example --strict-optional)

mypy.ini:

[mypy]
#mypy_path = $MYPYPATH

#
# Covered by --strict, with some turned off:
#
disallow_untyped_calls=True
disallow_untyped_defs=True
check_untyped_defs=True
# currently an issue with sql alchemy
disallow_subclassing_any=false
# Need to experiment/think about this one:
disallow_any_decorated=false
warn_redundant_casts=True
warn_return_any=True
warn_unused_ignores=True
# this seems to be at least somewhat non-functioning:
warn_unused_configs=True
#may be worth reconsidering this one:
no_implicit_optional=True
strict_optional=True

#
# Other: 
#
ignore_missing_imports=True


[mypy-sqlalchemy.*]
disallow_untyped_calls=False
disallow_untyped_defs=False

Note: originally reported in #2852

[bbarker]

cc @JelleZijlstra

[ilevkivskyi]

I cannot reproduce this, but my guess is that you are using ignore_missing_imports=True together with Python 3.6, so this is probably just a duplicate of #5389. Could you please try running with --python-version=3.7 (and --no-site-packages if needed)? And reopen if you find a repro.