diff --git a/t/test-lib.sh b/t/test-lib.sh
index c6afebb00d02808f2a990347c8b0479d825cce5b..1fb76abd14e358afb42774f0ffe1d4e70b749074 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -260,7 +260,7 @@ test_decode_color () {
 			if (n == 47) return "BWHITE";
 		}
 		{
-			while (match($0, /\x1b\[[0-9;]*m/) != 0) {
+			while (match($0, /\033\[[0-9;]*m/) != 0) {
 				printf "%s<", substr($0, 1, RSTART-1);
 				codes = substr($0, RSTART+2, RLENGTH-3);
 				if (length(codes) == 0)