Keep imports alphabetically sorted and their order homogeneous across
Python source files.
The isort project has more feature and is more active than the
flake8-import-order plugin.
Most issues caught were simply import ordering from the same module.
Where imports were purposefully placed out of order, tag with
isort:skip.
They are sometimes failed with python3.5 because the order of singledispatch
functions is not stable on python 3.5. This uses comparision via "in"
keyword to check the signature of singledispatch functions stably.
When documenting classes derived from typing.Generic (essentially all classes in the
typing module) the constructor signature would show an unhelpful (*args, **kwds).
typing.Generic has a __new__ method which was picked up by sphinx. With this patch it
is skipped and constructor signatures for generic classes are shown as they should.
sphinx.util.inspect:isproperty() does not considers that
cached_property decorator that has been added since Python 3.8 is
a kind of properties. This fixes it.
`typing.get_type_hints()` raises NameError when the target object
contains unresolavable type annotation (ex. TYPE_CHECKING). This
handles the exception and use unresolved annotations for type hints.
An annotated instance variable on super class is not documented when
derived class has also other annotated instance variables because
`obj.__annotations__` is overrided by derived class's type hints.
To get annotations of the target class correctly, this scans MRO to
get all of annotated instance variables.
So far, autodoc treats a "private" class attribute as a mere attribute.
But its name is mangled by python interpreter. This make it unmangled
name to be documented expectedly.
This fixes:
* Signatures defined by __new__
* Signatures defined by metaclasses
* Signatures defined by builtin base classes
All of these changes bring the sphinx docs inline with the behavior of `inspect.signature`.
Note that this changes autodoc to output `.. py:class: MyClass()` with parentheses even if no user-defined __init__ is present.
This is quite deliberate, as if no user-defined `__init__` is present the default is `object.__init__`, which indeed does not take arguments.
In Python 3, the default encoding of source files is utf-8. The encoding
cookie is now unnecessary and redundant so remove it. For more details,
see the docs:
https://docs.python.org/3/howto/unicode.html#the-string-type
> The default encoding for Python source code is UTF-8, so you can
> simply include a Unicode character in a string literal ...
Includes a fix for the flake8 header checks to stop expecting an
encoding cookie.
