[PATCH 2/2] send-email: rfc2047-quote subject lines with non-ascii characters

@@ -501,7 +501,12 @@ if ($compose) {
 	open(C,">",$compose_filename)
 		or die "Failed to open for writing $compose_filename: $!";
 	print C "From $sender # This line is ignored.\n";
-	printf C "Subject: %s\n\n", $initial_subject;
+	print C "Subject: ",
+		($initial_subject =~ /[^[:ascii:]]/ ?
+		quote_rfc2047($initial_subject) :
+		$initial_subject),
+		"\n";
+	print C "\n";
 	printf C <<EOT;
 GIT: Please enter your email below.
 GIT: Lines beginning in "GIT: " will be removed.

@@ -626,6 +631,14 @@ sub unquote_rfc2047 {
 	return wantarray ? ($_, $encoding) : $_;
 }
 
+sub quote_rfc2047 {
+	local $_ = shift;
+	my $encoding = shift || 'utf-8';
+	s/([^-a-zA-Z0-9!*+\/])/sprintf("=%02X", ord($1))/eg;
+	s/(.*)/=\?$encoding\?q\?$1\?=/;
+	return $_;
+}
+
 # use the simplest quoting being able to handle the recipient
 sub sanitize_address
 {

@@ -643,8 +656,7 @@ sub sanitize_address
 
 	# rfc2047 is needed if a non-ascii char is included
 	if ($recipient_name =~ /[^[:ascii:]]/) {
-		$recipient_name =~ s/([^-a-zA-Z0-9!*+\/])/sprintf("=%02X", ord($1))/eg;
-		$recipient_name =~ s/(.*)/=\?utf-8\?q\?$1\?=/;
+		$recipient_name = quote_rfc2047($recipient_name);
 	}
 
 	# double quotes are needed if specials or CTLs are included

@@ -210,4 +210,19 @@ test_expect_success '--compose respects user mime type' '
 	! grep "^Content-Type: text/plain; charset=utf-8" msgtxt1
 '
 
+test_expect_success '--compose adds MIME for utf8 subject' '
+	clean_fake_sendmail &&
+	echo y | \
+	  GIT_EDITOR=$(pwd)/fake-editor \
+	  GIT_SEND_EMAIL_NOTTY=1 \
+	  git send-email \
+	  --compose --subject utf8-sübjëct \
+	  --from="Example <nobody@example.com>" \
+	  --to=nobody@example.com \
+	  --smtp-server="$(pwd)/fake.sendmail" \
+	  $patches &&
+	grep "^fake edit" msgtxt1 &&
+	grep "^Subject: =?utf-8?q?utf8-s=C3=BCbj=C3=ABct?=" msgtxt1
+'
+
 test_done