indirectly decorated attr.s classes are not recognized

I'd like mypy to recognize attr.s decorated classes by "indirect" means.

To understand what I mean, consider the examples in the snippet below:

import attr

# example 1 (works with mypy)

@attr.s(auto_attribs=True, frozen=True)
class DirectlyDecorated:
    name: str


d = DirectlyDecorated('foo')  # no mypy error



# --- end example 1

# example 2 (does not work with mypy)

my_decorator = attr.s(auto_attribs=True, frozen=True)

@my_decorator
class IndirectlyDecorated:
    name: str


i = IndirectlyDecorated('bar')  # error: Too many arguments for "IndirectlyDecorated"

# --- end example 2


# example 3 (does not work with mypy)

class MyMeta(type):
    def __new__(cls, name, bases, dct):
        newcls = super().__new__(cls, name, bases, dct)
        newcls = my_decorator(newcls)
        return newcls


class MetaDecorated(metaclass=MyMeta):
    name: str


m = MetaDecorated('baz')  # error: Too many arguments for "MetaDecorated"

# --- end example 3

Running git master version of mypy as of today, with no arguments, I get:

snippet.py:25: error: Too many arguments for "IndirectlyDecorated"
snippet.py:43: error: Too many arguments for "MetaDecorated"

So, example 1 works as expected. Examples 2 and 3 do not work:

The same happens when using kw_only=True (that is example1 with kw_only=True works, but neither examples 2 nor 3 work with kw_only=True). In that case, the error reported is, of course,

snippet.py:25: error: Unexpected keyword argument "name" for "IndirectlyDecorated"
snippet.py:43: error: Unexpected keyword argument "name" for "MetaDecorated"

I'd like mypy to recognize the above cases so that example 2 and 3 work (with both kw_only=True and kw_only=False)

Thank you

Start by reproducing the issue with the snippet.py examples and running mypy on the direct, indirect, and metaclass decoration cases. Trace how mypy recognizes attr.s and compare that with the indirect decorator and metaclass paths. Done means examples 2 and 3 no longer report constructor argument errors, including the kw_only variants.