Re: [PATCH 0/6] Create Git/Packet.pm

[Bryan Turner <bturner@atlassian.com>]

On Thu, Oct 26, 2017 at 2:07 AM, Jacob Keller <jacob.keller@gmail.com> wrote:
> On Wed, Oct 25, 2017 at 10:38 PM, Junio C Hamano <gitster@pobox.com> wrote:
>> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>>
>>> Note that the correct blib path starts with `C:\BuildAgent\_work` and
>>> the line
>>>
>>>       use lib (split(/:/, $ENV{GITPERLLIB}));
>>>
>>> splits off the drive letter from the rest of the path. Obviously, this
>>> fails to Do The Right Thing, and simply points to Yet Another Portability
>>> Problem with Git's reliance on Unix scripting.
>>
>> In our C code, we have "#define PATH_SEP ';'", and encourage our
>> code to be careful and use it.  Is there something similar for Perl
>> scripts, I wonder.
>>
>> I notice that t/{t0202,t9000,t9700}/test.pl share the same
>> split(/:/, $ENV{GITPERLLIB}); forcing this specific variable to use
>> the non-platform convention to accomodate the use of split(/:/)
>> certainly is a workaround, but it does feel dirty.
>>
>> It is hard to imagine that we were the first people who wants to
>> split the value of a variable into a list, where the value is a list
>> of paths, concatenated into a single string with a delimiter that
>> may be platform specific.  I wonder if we are going against a best
>> practice established in the Perl world, simply because we don't know
>> about it (i.e. basically, it would say "don't split at a colon
>> because not all world is Unix; use $this_module instead", similar to
>> "don't split at a slash, use File::Spec instead to extract path
>> components").
>>
>
> I thought there was a way to do this in File::Spec, but that's only
> for splitting regular paths, and not for splitting a list of paths
> separated by ":" or ";"
>
> We probably should find a better solution to allow this to work with
> windows style paths...? I know that python provides os.pathsep, but I
> haven't seen an equivalent for perl yet.
>
> The Env[1] core modules suggests using $Config::Config{path_sep}[2]..
> maybe we should be using this?

I was testing this recently on the Perl included with Git for Windows
and it returns : for the path separator even though it's on Windows,
so I don't think that would work. The Perl in Git for Windows seems to
want UNIX-style inputs (something Dscho seemed to allude to in his
response earlier.). I'm not sure why it's that way, but he probably
knows.

Bryan

(Pardon my previous blank message; Gmail fail.)

>
> Thanks,
> Jake
>
> [1] https://perldoc.perl.org/Env.html
> [2] https://perldoc.perl.org/Config.html