TIMEDIFF might give wrong result when casting values

[YangKeao]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

SELECT TIMEDIFF(CAST('2024-05-01' AS DATE), '2024-05-01 12:30:45');
SELECT TIMEDIFF(123456.789, 987654.321);
SELECT TIMEDIFF('12:34', '56:78');
SELECT TIMEDIFF('1.5:0:0', '3:0:0');

2. What did you expect to see? (Required)

mysql> SELECT TIMEDIFF(CAST('2024-05-01' AS DATE), '2024-05-01 12:30:45');
+-------------------------------------------------------------+
| TIMEDIFF(CAST('2024-05-01' AS DATE), '2024-05-01 12:30:45') |
+-------------------------------------------------------------+
| NULL                                                        |
+-------------------------------------------------------------+
1 row in set (0.05 sec)

mysql> SELECT TIMEDIFF(123456.789, 987654.321);
+----------------------------------+
| TIMEDIFF(123456.789, 987654.321) |
+----------------------------------+
| NULL                             |
+----------------------------------+
1 row in set, 1 warning (0.01 sec)

mysql> SELECT TIMEDIFF('12:34', '56:78');
+----------------------------+
| TIMEDIFF('12:34', '56:78') |
+----------------------------+
| NULL                       |
+----------------------------+
1 row in set, 1 warning (0.00 sec)

mysql> SELECT TIMEDIFF('1.5:0:0', '3:0:0');
+------------------------------+
| TIMEDIFF('1.5:0:0', '3:0:0') |
+------------------------------+
| -02:59:58.5                  |
+------------------------------+
1 row in set, 1 warning (0.00 sec)

3. What did you see instead (Required)

mysql> SELECT TIMEDIFF(CAST('2024-05-01' AS DATE), '2024-05-01 12:30:45');
+-------------------------------------------------------------+
| TIMEDIFF(CAST('2024-05-01' AS DATE), '2024-05-01 12:30:45') |
+-------------------------------------------------------------+
| -12:30:45                                                   |
+-------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> SELECT TIMEDIFF(123456.789, 987654.321);
+----------------------------------+
| TIMEDIFF(123456.789, 987654.321) |
+----------------------------------+
| 12:34:56.789                     |
+----------------------------------+
1 row in set, 1 warning (0.00 sec)

mysql> SELECT TIMEDIFF('12:34', '56:78');
+----------------------------+
| TIMEDIFF('12:34', '56:78') |
+----------------------------+
| 12:34:00                   |
+----------------------------+
1 row in set, 1 warning (0.00 sec)

mysql> SELECT TIMEDIFF('1.5:0:0', '3:0:0');
+------------------------------+
| TIMEDIFF('1.5:0:0', '3:0:0') |
+------------------------------+
| -02:59:58                    |
+------------------------------+
1 row in set, 1 warning (0.00 sec)

4. What is your TiDB version? (Required)