git svn: make empty directory creation gc-aware

The "git svn gc" command creates and appends to unhandled.log.gz
files which should be parsed before the uncompressed
unhandled.log files.

Reported-by: Robert Zeh
Signed-off-by: Eric Wong <normalperson@yhbt.net>

git-svn.perl

@@ -2740,21 +2740,44 @@ sub do_fetch {
 
 sub mkemptydirs {
 	my ($self, $r) = @_;
-	my %empty_dirs = ();
 
-	open my $fh, '<', "$self->{dir}/unhandled.log" or return;
-	binmode $fh or croak "binmode: $!";
-	while (<$fh>) {
-		if (defined $r && /^r(\d+)$/) {
-			last if $1 > $r;
-		} elsif (/^  \+empty_dir: (.+)$/) {
-			$empty_dirs{$1} = 1;
-		} elsif (/^  \-empty_dir: (.+)$/) {
-			my @d = grep {m[^\Q$1\E(/|$)]} (keys %empty_dirs);
-			delete @empty_dirs{@d};
+	sub scan {
+		my ($r, $empty_dirs, $line) = @_;
+		if (defined $r && $line =~ /^r(\d+)$/) {
+			return 0 if $1 > $r;
+		} elsif ($line =~ /^  \+empty_dir: (.+)$/) {
+			$empty_dirs->{$1} = 1;
+		} elsif ($line =~ /^  \-empty_dir: (.+)$/) {
+			my @d = grep {m[^\Q$1\E(/|$)]} (keys %$empty_dirs);
+			delete @$empty_dirs{@d};
+		}
+		1; # continue
+	};
+
+	my %empty_dirs = ();
+	my $gz_file = "$self->{dir}/unhandled.log.gz";
+	if (-f $gz_file) {
+		if (!$can_compress) {
+			warn "Compress::Zlib could not be found; ",
+			     "empty directories in $gz_file will not be read\n";
+		} else {
+			my $gz = Compress::Zlib::gzopen($gz_file, "rb") or
+				die "Unable to open $gz_file: $!\n";
+			my $line;
+			while ($gz->gzreadline($line) > 0) {
+				scan($r, \%empty_dirs, $line) or last;
+			}
+			$gz->gzclose;
 		}
 	}
-	close $fh;
+
+	if (open my $fh, '<', "$self->{dir}/unhandled.log") {
+		binmode $fh or croak "binmode: $!";
+		while (<$fh>) {
+			scan($r, \%empty_dirs, $_) or last;
+		}
+		close $fh;
+	}
 
 	my $strip = qr/\A\Q$self->{path}\E(?:\/|$)/;
 	foreach my $d (sort keys %empty_dirs) {

t/t9146-git-svn-empty-dirs.sh

@@ -114,5 +114,29 @@ test_expect_success 'removed top-level directory does not exist' '
 	test ! -e removed/d
 
 '
+unhandled=.git/svn/refs/remotes/git-svn/unhandled.log
+test_expect_success 'git svn gc-ed files work' '
+	(
+		cd removed &&
+		git svn gc &&
+		: Compress::Zlib may not be available &&
+		if test -f "$unhandled".gz
+		then
+			svn mkdir -m gz "$svnrepo"/gz &&
+			git reset --hard $(git rev-list HEAD | tail -1) &&
+			git svn rebase &&
+			test -f "$unhandled".gz &&
+			test -f "$unhandled" &&
+			for i in a b c "weird file name" gz "! !"
+			do
+				if ! test -d "$i"
+				then
+					echo >&2 "$i does not exist"
+					exit 1
+				fi
+			done
+		fi
+	)
+'
 
 test_done