+- while (my $parsed = parse_diff_tree(\@raw_lines)) {
+- push @ci, $parsed;
+- }
++
++ # Test to see if branch actually exists yet.
++ if (run_or_non('git', 'show-ref', '--quiet', '--verify', '--', 'refs/heads/' . $config{gitmaster_branch}) ) {
++ @raw_lines = run_or_die('git', 'log', @opts,
++ '--pretty=raw', '--raw', '--abbrev=40', '--always', '-c',
++ '-r', $sha1, '--', '.');
++
++ while (my $parsed = parse_diff_tree(\@raw_lines)) {
++ push @ci, $parsed;
++ }
+
+- warn "Cannot parse commit info for '$sha1' commit" if !@ci;
++ warn "Cannot parse commit info for '$sha1' commit" if !@ci;
++ };
+
+ return wantarray ? @ci : $ci[0];
+ }
+</pre>
+
+My concern is that this adds a bit of slowdown (git show-ref is fast, but
+It's still extra work) to a very hot code path that is run to eg,
+update recentchanges after every change.
+
+Seems not ideal to do extra work every time to handle a case
+that will literally happen a maximum of once in the entire lifecycle of a
+wiki (and zero times more typically, since the setup automator puts in a
+.gitignore file that works around this problem).
+
+So as to not just say "no" ... what if it always tried to run git log,
+and if it failed (or returned no parsed lines), then it could look
+at git show-ref to deduce whether to throw an error or not.
+--[[Joey]]
+
+> Ah, but then git-log would still complain "bad revision 'HEAD'"
+> --[[Joey]]
+
+<pre>
+@@ -474,7 +478,10 @@ sub rcs_update () {