[PATCH] send-email: don't cc *-by lines with '-' prefix

[Baruch Siach <baruch@tkos.co.il>]

Since commit ef0cc1df90f6b ("send-email: also pick up cc addresses from
-by trailers") in git version 2.20, git send-email adds to cc list
addresses from all *-by lines. As a side effect a line with
'-Signed-off-by' is now also added to cc. This makes send-email pick
lines from patches that remove patch files from the git repo. This is
common in the Buildroot project that often removes (and adds) patch
files that have 'Signed-off-by' in their patch description part.

Consider only *-by lines that start with [a-z] (case insensitive) to
avoid unrelated addresses in cc.

Cc: Joe Perches <joe@perches.com>
Cc: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
 git-send-email.perl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/git-send-email.perl b/git-send-email.perl
index 8eb63b5a2f8d..5656ba83d9b1 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -1693,7 +1693,7 @@ sub process_file {
 	# Now parse the message body
 	while(<$fh>) {
 		$message .=  $_;
-		if (/^([a-z-]*-by|Cc): (.*)/i) {
+		if (/^([a-z][a-z-]*-by|Cc): (.*)/i) {
 			chomp;
 			my ($what, $c) = ($1, $2);
 			# strip garbage for the address we'll use:
-- 
2.20.1