Allow path_type of the Path type to accept a callable (#405_)

[termim]

This would allow to convert path names to pathlib.Path instances
for example.

closes #405

[LucidOne]

I looks like this assertion needs to be uncommented.

[LucidOne]

Ran tox on this locally

  py37: commands succeeded
SKIPPED:  py36: InterpreterNotFound: python3.6
  py35: commands succeeded
SKIPPED:  py34: InterpreterNotFound: python3.4
  py27: commands succeeded
SKIPPED:  pypy3: InterpreterNotFound: pypy3
SKIPPED:  pypy: InterpreterNotFound: pypy

I also tested this with an application I'm developing by adding git+https://github.com/termim/click.git@I405#egg=click to my requirements.txt and it works as advertised.

However, using pathlib.Path as the path_type with Click7.0

@click.option('--config', '-c', type=click.Path(exists=True,dir_okay=False,path_type=pathlib.Path), required=False, help='Config file')

sets config to type bytes though backwards compatibility can be maintained as needed with

config = pathlib.Path(config.decode()) if isinstance(config,bytes) else config

as pathlib.Path(None) isn't accepted.

Also, I'm not sure if there would be an advantage to setting this to isinstance(input,os.PathLike) but it may be worth considering.

Aside from the above it looks good to me, I would like to see this merged.

[termim]

I looks like this assertion needs to be uncommented.

Done.

[termim]

However, using pathlib.Path as the path_type with Click7.0

@click.option('--config', '-c', type=click.Path(exists=True,dir_okay=False,path_type=pathlib.Path), required=False, help='Config file')

sets config to type bytes though backwards compatibility can be maintained as needed with

I can't reproduce this:

click>$ python3 --version
Python 3.5.2
click>$ grep __version__ ./click/click/__init__.py 
__version__ = '7.1.dev'
click>$ cat t.py
import click
import pathlib

@click.command()
@click.option('--config', '-c', type=click.Path(exists=True,dir_okay=False,path_type=pathlib.Path), required=False, help='Config file')
def hello(config):
    click.echo('Hello %s!' % type(config))

if __name__ == '__main__':
    hello()
click>$ 
click>$ PYTHONPATH=./click python3 ./t.py -c ./t.py
Hello <class 'pathlib.PosixPath'>!
click>$ 

config = pathlib.Path(config.decode()) if isinstance(config,bytes) else config

as pathlib.Path(None) isn't accepted.

Also, I'm not sure if there would be an advantage to setting this to isinstance(input,os.PathLike) but it may be worth considering.

That would make click require pathlib2 for python2 ...

[LucidOne]

However, using pathlib.Path as the path_type with Click7.0

@click.option('--config', '-c', type=click.Path(exists=True,dir_okay=False,path_type=pathlib.Path), required=False, help='Config file')

sets config to type bytes though backwards compatibility can be maintained as needed with

I can't reproduce this:

click>$ python3 --version
Python 3.5.2
click>$ grep __version__ ./click/click/__init__.py 
__version__ = '7.1.dev'
click>$ cat t.py
import click
import pathlib

@click.command()
@click.option('--config', '-c', type=click.Path(exists=True,dir_okay=False,path_type=pathlib.Path), required=False, help='Config file')
def hello(config):
    click.echo('Hello %s!' % type(config))

if __name__ == '__main__':
    hello()
click>$ 
click>$ PYTHONPATH=./click python3 ./t.py -c ./t.py
Hello <class 'pathlib.PosixPath'>!
click>$ 

I was getting bytes using path_type=pathlib.Path without your PR on version 7.0.

$ python t.py -c t.py
Hello <class 'bytes'>!

[termim]

I was getting bytes using path_type=pathlib.Path without your PR on version 7.0.

Ah, yes, without this #1234 it always returns bytes if path_type is not a string ...

[LucidOne]

config = pathlib.Path(config.decode()) if isinstance(config,bytes) else config
provides backwards compatibility, so application developers can move to pathlib while waiting for your PR to make it downstream.