viewdiff: avoid repeat variable expansion

This is worth a 1-2% speedup in t/perf-msgview.t rendering 2620
messages currently in https://public-inbox.org/meta/

diff --git a/lib/PublicInbox/ViewDiff.pm b/lib/PublicInbox/ViewDiff.pm
index 6b8d94372405486ca2223e0fc057e79cb24691ac..411ed2bb7d4fb53d1b811a2bcf29c76c4265ae01 100644 (file)
--- a/lib/PublicInbox/ViewDiff.pm
+++ b/lib/PublicInbox/ViewDiff.pm
@@ -159,7 +159,7 @@ sub flush_diff ($$$) {
                        $state == DSTATE_INIT or
                                to_state($dst, $state, DSTATE_INIT);
                        $$dst .= $s;
-               } elsif ($s =~ m!^diff --git ($PATH_A) ($PATH_B)$!) {
+               } elsif ($s =~ m!^diff --git ($PATH_A) ($PATH_B)$!o) {
                        my ($pa, $pb) = ($1, $2);
                        if ($state != DSTATE_HEAD) {
                                to_state($dst, $state, DSTATE_HEAD);
@@ -194,8 +194,8 @@ sub flush_diff ($$$) {
                        $$dst .= '</span>';
                        $state = DSTATE_CTX;
                        $$dst .= to_html($linkify, $s);
-               } elsif ($s =~ m!^--- (?:$PATH_A)! ||
-                        $s =~ m!^\+{3} (?:$PATH_B)!)  {
+               } elsif ($s =~ m!^--- (?:$PATH_A)!o ||
+                        $s =~ m!^\+{3} (?:$PATH_B)!o)  {
                        # color only (no oid link) if missing dctx->{oid_*}
                        $state <= DSTATE_STAT and
                                to_state($dst, $state, DSTATE_HEAD);