paramiko stubs seem incorrect for python3

[mrodden]

I am getting a bunch of errors from mypy with the types-paramiko package.

Some are imports that are not in the stubs for paramiko like paramiko.PublicBlob which is an alias import from paramiko.pkey.PublicBlob (see https://github.com/paramiko/paramiko/blob/master/paramiko/__init__.py#L65)

Others seem to be issues between python2 and python3 where many of the object stubs are declaring type str when in fact paramiko is treating it like a bytes (see https://github.com/python/typeshed/blob/master/stubs/paramiko/paramiko/pkey.pyi#L36 and https://github.com/paramiko/paramiko/blob/master/paramiko/pkey.py#L679-L681)

I'm not sure if there is a nice way to resolve this, as it is obviously an str in py2 but bytes in py3.

I have currently chosen to ignore the types-paramiko package in my project, as it causes too many false check errors with mypy.

[Akuli]

str in py2 but bytes in py3

In this case, you should just use bytes. In Python 2, str and bytes are the same, and unicode is different.

[mrodden]

The issue can be highlight with the following

pub_blob = paramiko.pkey.PublicBlob.from_file("/path/to/file")
rsa_key = paramiko.pkey.RSAKey(data=pub_blob.key_blob)

The second line causes a mypy arg-type issue, since the stubs say that key_blob is a str and the data kwarg to RSAKey.__init__ is a bytes.

The key_blob IS a bytes though, so it works fine at runtime.

[mrm-david]

Another example : in exec_command the parameter command is str in the stubs; but it can actually accept byte as well since it eventually gets passed to b()which converts it to byte unless it was already byte, in which cases it returns it untouched.

[Akuli]

PRs to improve the stubs are welcome :)

[JelleZijlstra]

In #10109 I fix two of the specific issues mentioned above. Anything else is best handled in a focused issue/PR that describes exactly what type is wrong.