Cutting release 0.18.2.

[dhermes]

No description provided.

[dhermes]

@jonparrott Should I add a link to https://www.python.org/dev/peps/pep-0397/? Are there better docs somewhere for py.exe?

UPDATE: https://docs.python.org/3/using/windows.html#launcher

[dhermes]

@jonparrott It just occurred to me that #53 may come up short for 32-bit Python. Maybe we should hold off on a release?

[theacodes]

@dhermes WDYT? How common is 32bit Python? How much of an issue will it cause?

[dhermes]

OK I rebased this after #64 and #65. I also added a link to the launcher in the CHANGELOG

[dhermes]

TL;DR

• nox allows no way to explicitly ask for 32-bit
• If a system has both 32- and 64-bit versions of the same Python, the 64-bit version wins via py.exe
• nox looks for pythonX.Y on the PATH before using py.exe but the official Python.org binaries only ship python.exe and pythonw.exe (i.e. you can't simply add a directory to your PATH)

---

Launcher sleuthing. My current Windows 10 install has 32- and 64-bit versions of 2.7, 3.5 and 3.6.

I want to know where they are installed and their "bit"-ness:

# info.py
import platform
import sys


def main():
    print(sys.executable)
    print(platform.architecture())


if __name__ == '__main__':
    main()

Running this:

C:\Users\dhermes>py -2.7 info.py
C:\Python27\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>py -2.7-32 info.py
C:\Python27-32\python.exe
('32bit', 'WindowsPE')

C:\Users\dhermes>py -3.5 info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python35\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>py -3.5-32 info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python35-32\python.exe
('32bit', 'WindowsPE')

C:\Users\dhermes>py -3.6 info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python36\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>py -3.6-32 info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python36-32\python.exe
('32bit', 'WindowsPE')

Now if I manually use the 3.6.3 Windows 64-bit web-based installer to uninstall it (temporarily), the launcher says:

C:\Users\dhermes>py -3.6 info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python36-32\python.exe
('32bit', 'WindowsPE')

C:\Users\dhermes>py -3.6-32 info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python36-32\python.exe
('32bit', 'WindowsPE')

The way the current behavior works (only on Windows, mind you), if the value of interpreter is explicitly provided, but not found on the PATH, then the interpreter value must be of the form pythonX.Y (where X and Y are digits):

>>> import re
>>>
>>> def f(interpreter):
...     match = re.match(r'^python(?P<ver>\d\.\d)$', interpreter)
...     if match is None:
...         return None
...     else:
...         return match.group('ver')
...
>>>
>>> f('python2.7')
'2.7'
>>> f('python3.6')
'3.6'
>>> f('python2.7-32') is None
True
>>> f('python8.7')
'8.7'

Since nox does "defer" to the path, this is somewhat OK, but none of the official Python.org versions come with pythonX.Y:

C:\Users\dhermes>set OLD_PATH=%PATH%

2.7 64-bit

C:\Users\dhermes>set PATH=C:\Python27;%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Python27\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Python27\python*.exe
python.exe
pythonw.exe

2.7 32-bit

C:\Users\dhermes>set PATH=C:\Python27-32;%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Python27-32\python.exe
('32bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Python27-32\python*.exe
python.exe
pythonw.exe

3.5 64-bit

C:\Users\dhermes>set PATH=C:\Users\dhermes\AppData\Local\Programs\Python\Python35;%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python35\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Users\dhermes\AppData\Local\Programs\Python\Python35\python*.exe
python.exe
pythonw.exe

3.5 32-bit

C:\Users\dhermes>set PATH=C:\Users\dhermes\AppData\Local\Programs\Python\Python35-32;%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python35-32\python.exe
('32bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Users\dhermes\AppData\Local\Programs\Python\Python35-32\python*.exe
python.exe
pythonw.exe

3.6 64-bit

C:\Users\dhermes>set PATH=C:\Users\dhermes\AppData\Local\Programs\Python\Python36;%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python36\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Users\dhermes\AppData\Local\Programs\Python\Python36\python*.exe
python.exe
pythonw.exe

3.6 32-bit

C:\Users\dhermes>set PATH=C:\Users\dhermes\AppData\Local\Programs\Python\Python36-32;%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Users\dhermes\AppData\Local\Programs\Python\Python36-32\python.exe
('32bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Users\dhermes\AppData\Local\Programs\Python\Python36-32\python*.exe
python.exe
pythonw.exe

Restore

C:\Users\dhermes>set PATH=%OLD_PATH%

C:\Users\dhermes>python info.py
C:\Users\dhermes\AppData\Local\Continuum\Miniconda2\python.exe
('64bit', 'WindowsPE')

C:\Users\dhermes>dir /B C:\Users\dhermes\AppData\Local\Continuum\Miniconda2\python*.exe
python.exe
pythonw.exe

[theacodes]

@dhermes is there anything we need to do to address that in this release? It seems like asking explicitly for a 32bit interpreter should be a separate feature.

[dhermes]

@jonparrott I suppose yes it could be a separate feature (definitely relates to #60 since that is 32- vs. 64- on OS X and to #62 since not all users would care about passing the architecture)

Press the big green button?

(Then maybe I should copy-paste this into a new issue?)

[theacodes]

Press the big green button?

Go for it.

(Then maybe I should copy-paste this into a new issue?)

Sounds good.