[ssoma PATCH 1/2] extractor: warn about v2 repositories

[Eric Wong <e@80x24.org>]

ssoma was a misguided effort and won't be updated to support v2,
but at least spit out a warning about v2 repos.

Reported-by: Yaron Scheffer <yscheffer@protonmail.com>
---
 lib/Ssoma/Extractor.pm | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/lib/Ssoma/Extractor.pm b/lib/Ssoma/Extractor.pm
index baf9adb..5c10eec 100644
--- a/lib/Ssoma/Extractor.pm
+++ b/lib/Ssoma/Extractor.pm
@@ -28,6 +28,17 @@ sub _flist {
 	\@rv
 }
 
+sub warn_v2 {
+	my ($self) = @_;
+	if (system('git cat-file blob HEAD:m >/dev/null 2>&1') == 0 ||
+	    system('git cat-file blob HEAD:d >/dev/null 2>&1') == 0) {
+		warn <<"";
+$self->{git}->{git_dir} looks like a public-inbox v2 repo.
+ssoma is deprecated and does not support v2 repositories
+
+	}
+}
+
 sub _extract {
 	my ($self, $target, $since) = @_;
 	my $git = $self->{git};
@@ -82,11 +93,16 @@ sub _extract {
 		# tricking us into extracting the same message twice;
 		# MDA will keep the original in sufficiently-identical messages
 		my $cmd = "git diff-tree -r --name-only -M100% --diff-filter=A";
-		$new = _flist("$cmd $last $tip");
+		$new = [];
+		if ($last ne $tip) {
+			$new = _flist("$cmd $last $tip");
+			warn_v2($self) unless scalar(@$new);
+		}
 	} else {
 		# new maildir or mbox (to us), import everything in the
 		# current tree
 		$new = _flist("git ls-tree -r --name-only $tip");
+		warn_v2($self) unless scalar(@$new);
 	}
 
 	my $i = 0;
-- 
EW