Re: [PATCH v6 2/3] Makefile: add Perl runtime prefix support

From

Daniel Jacques <dnj@google.com>

Date

Mar 19, 2018, 19:47 UTC

Message-ID

<CAD1RUU-3Q_SYvJorU+vEY2-0CPMZ1eL-41Z6eL7Sq4USiJ0U+w@mail.gmail.com>

In-Reply-To

<87y3inc1my.fsf@evledraar.gmail.com>

> I think it would be more idiomatic and more paranoid (we'll catch bugs)
> to do:

>       my $exec_path;
>       if (exists $ENV{GIT_EXEC_PATH}) {
>           $exec_path = $ENV{GIT_EXEC_PATH};
>       } else {
>           [...]
>       }

> I.e. we're interested if we got passed GIT_EXEC_PATH, so let's see if it
> exists in the env hash, and then use it as-is. If we have some bug where
> it's an empty string we'd like to know, presumably...

Good idea, done.

> > +
> > +     # Trim off the relative gitexecdir path to get the system path.
> > +     (my $prefix = $exec_path) =~ s=${gitexecdir_relative}$==;

> The path could contain regex metacharacters, so let's quote those via:

>       (my $prefix = $exec_path) =~ s/\Q$gitexecdir_relative\E$//;

> This also nicely gets us rid of the more verbose ${} form, which makes
> esnse when we're doing ${foo}$ instead of the arguably less readbale
> $foo$, but when it's \Q$foo\E$ it's clear what's going on.