Improve validation of object keys

Author: mohd-akram

src/jawk.awk

@@ -283,7 +283,7 @@ function __parse_object(path, sep, i, raw_value, key, colon, value, raw_key) {
 			raw_value = raw_value key
 			break
 		}
-		if (length(key) < 2) __error(key)
+		if (length(key) < 2 || substr(key, 1, 1) != "\"") __error(key)
 		raw_key = key
 		key = substr(key, 2, length(key) - 2)
 		colon = __get_token()

test/run.sh

@@ -217,6 +217,12 @@ err=$(cat test/err; rm test/err)
 [ "$out" = 1 ]
 [ "$err" = 'jawk: unexpected token "' ]
 
+test "unexpected token in object key (number)"
+out=$(echo '{12:34}' | jawk '{print}' 2>test/err; echo $?)
+err=$(cat test/err; rm test/err)
+[ "$out" = 1 ]
+[ "$err" = 'jawk: unexpected token 12' ]
+
 test "unexpected token in object colon"
 out=$(echo '{"x"c' | jawk '{print}' 2>test/err; echo $?)
 err=$(cat test/err; rm test/err)