git: reload alternates file on missing blob

Since we'll be adding new repositories to the `alternates' file
in git, we must restart the `git cat-file --batch' process as
git currently does not detect changes to the alternates file
in long-running cat-file processes.

Don't bother with the `--batch-check' process since we won't be
using it with v2.

1 files changed, 21 insertions, 0 deletions

diff --git a/t/git.t b/t/git.t
index ab588a15..7f96293f 100644
--- a/t/git.t
+++ b/t/git.t
@@ -6,6 +6,7 @@ use Test::More;
 use File::Temp qw/tempdir/;
 my $dir = tempdir('pi-git-XXXXXX', TMPDIR => 1, CLEANUP => 1);
 use Cwd qw/getcwd/;
+use PublicInbox::Spawn qw(popen_rd);
 
 use_ok 'PublicInbox::Git';
 {
@@ -142,4 +143,24 @@ if (1) {
         ok($gcf->packed_bytes > 0, 'packed size is positive');
 }
 
+if ('alternates reloaded') {
+        my $alt = tempdir('pi-git-XXXXXX', TMPDIR => 1, CLEANUP => 1);
+        my @cmd = ('git', "--git-dir=$alt", qw(hash-object -w --stdin));
+        is(system(qw(git init -q --bare), $alt), 0, 'create alt directory');
+        open my $fh, '<', "$alt/config" or die "open failed: $!\n";
+        my $rd = popen_rd(\@cmd, {}, { 0 => fileno($fh) } );
+        close $fh or die "close failed: $!";
+        chomp(my $remote = <$rd>);
+        my $gcf = PublicInbox::Git->new($dir);
+        is($gcf->cat_file($remote), undef, "remote file not found");
+        open $fh, '>>', "$dir/objects/info/alternates" or
+                        die "open failed: $!\n";
+        print $fh "$alt/objects" or die "print failed: $!\n";
+        close $fh or die "close failed: $!";
+        my $found = $gcf->cat_file($remote);
+        open $fh, '<', "$alt/config" or die "open failed: $!\n";
+        my $config = eval { local $/; <$fh> };
+        is($$found, $config, 'alternates reloaded');
+}
+
 done_testing();