Re: [PATCH] git-svn: do not reuse caches memoized for a different architecture

[Eric Wong]

Johannes Schindelin <johannes.schinde...@gmx.de> wrote:
> +++ b/perl/Git/SVN.pm
> @@ -1658,6 +1658,11 @@ sub tie_for_persistent_memoization {
>       if ($memo_backend > 0) {
>               tie %$hash => 'Git::SVN::Memoize::YAML', "$path.yaml";
>       } else {
> +             # first verify that any existing file can actually be loaded
> +             # (it may have been saved by an incompatible version)
> +             if (-e "$path.db") {
> +                     unlink "$path.db" unless eval { retrieve("$path.db"); 1 
> };
> +             }

That retrieve() call is unlikely to work without "use Storable"
to import it into the current package.

I also favor setting "$path.db" once to detect typos and avoid
going over 80 columns.  Additionally, having error-checking for
unlink might be useful.

So perhaps squashing this on top:

diff --git a/perl/Git/SVN.pm b/perl/Git/SVN.pm
index 025c894..b3c1460 100644
--- a/perl/Git/SVN.pm
+++ b/perl/Git/SVN.pm
@@ -1660,10 +1660,15 @@ sub tie_for_persistent_memoization {
        } else {
                # first verify that any existing file can actually be loaded
                # (it may have been saved by an incompatible version)
-               if (-e "$path.db") {
-                       unlink "$path.db" unless eval { retrieve("$path.db"); 1 
};
+               my $db = "$path.db";
+               if (-e $db) {
+                       use Storable qw(retrieve);
+
+                       if (!eval { retrieve($db); 1 }) {
+                               unlink $db or die "unlink $db failed: $!";
+                       }
                }
-               tie %$hash => 'Memoize::Storable', "$path.db", 'nstore';
+               tie %$hash => 'Memoize::Storable', $db, 'nstore';
        }
 }
 

Thoughts?  Thanks.