ui-log.c: allow commit range as search expression

Inspired-by: Johan Herland <johan@herland.net>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
diff --git a/ui-log.c b/ui-log.c
index 0947604..4441d1d 100644
--- a/ui-log.c
+++ b/ui-log.c
@@ -146,10 +146,13 @@
 
 	argv[1] = disambiguate_ref(tip);
 
-	if (grep && pattern && (!strcmp(grep, "grep") ||
-				!strcmp(grep, "author") ||
-				!strcmp(grep, "committer")))
-		argv[argc++] = fmt("--%s=%s", grep, pattern);
+	if (grep && pattern) {
+		if (!strcmp(grep, "grep") || !strcmp(grep, "author") ||
+		    !strcmp(grep, "committer"))
+			argv[argc++] = fmt("--%s=%s", grep, pattern);
+		if (!strcmp(grep, "range"))
+			argv[1] = pattern;
+	}
 
 	if (path) {
 		argv[argc++] = "--";