bug#21376: 25.0.50; Python tests fail on MS-Windows -- issues with the prompt

[Eli Zaretskii <eliz@gnu.org>]

> From: Noam Postavsky <npostavs@users.sourceforge.net>
> Date: Wed, 16 Aug 2017 12:14:56 -0400
> Cc: 21376@debbugs.gnu.org, Fabián E. Gallina <fgallina@gnu.org>
> 
> On Wed, Aug 16, 2017 at 10:26 AM, Eli Zaretskii <eliz@gnu.org> wrote:
> >
> > Thanks, but after applying the patch I still see the same 4 tests
> > mentioned above failing.  Do I need to do something in addition to
> > just running the test, as in
> >
> >   cd test && make lisp/progmodes/python-tests.log
> 
> Hmm, that's odd, it works for me. Can you check what the following
> expressions insert:
> 
> (let ((pyfile (make-temp-file "test" nil ".py")))
>   (unwind-protect
>       (progn (let ((inhibit-eol-conversion nil))
>                (with-temp-file pyfile
>                  (insert "print('hello world')\n")))
>              (call-process "python2" pyfile '(t t) nil
>                            "-i" "-u"))
>     (delete-file pyfile)))
> 
> (let ((pyfile (make-temp-file "test" nil ".py")))
>   (unwind-protect
>       (progn (let ((inhibit-eol-conversion t))
>                (with-temp-file pyfile
>                  (insert "print('hello world')\n")))
>              (call-process "python2" pyfile '(t t) nil
>                            "-i" "-u"))
>     (delete-file pyfile)))
> 
> I get this for the first (where ^M is really a carriage return character)
> 
>     Python 2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:53:40)
>       [MSC v.1500 64 bit (AMD64)] on win32
>     Type "help", "copyright", "credits" or "license" for more information.
>     >>>   File "<stdin>", line 1
>         print('hello world')^M
>                             ^
>     SyntaxError: invalid syntax
>     >>>
> 
> and this for the second:
> 
>     Python 2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:53:40)
>       [MSC v.1500 64 bit (AMD64)] on win32
>     Type "help", "copyright", "credits" or "license" for more information.
>     >>> hello world
>     >>>

Same here, except that Python version is 2.6.6.  Also, I needed to
replace "python2" with an explicit absolute file name of python.exe,
as I don't have "python2" here and Python is not on PATH.  But I don't
believe these differences are important, are they?