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

Hi Bryan,

On Thu, 26 Oct 2017, Bryan Turner wrote:

On Thu, Oct 26, 2017 at 2:07 AM, Jacob Keller [off-list ref] wrote:

quoted

On Wed, Oct 25, 2017 at 10:38 PM, Junio C Hamano [off-list ref] wrote:

quoted

Johannes Schindelin [off-list ref] writes:

quoted

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.

MSYS2 Perl is essentially Cygwin's Perl ported over to MSYS2. And Cygwin
tries to keep everything as pseudo Unix as possible, to make it easier to
port software (if you think Git's source code is the only source code
woefully unprepared for semicolons as path separators, you just need to
buy me a few beers to hear plenty of war stories).

Ciao,
Dscho