fix: do not error if a timestamp is null in msql (#235)

[fixes #221]

Author: mcollina

packages/mysql/src/__tests__/dates.test.mysql.ts

@@ -439,3 +439,54 @@ test('DATE as utc', async () => {
   ]);
   await db.dispose();
 });
+
+test('timestamp NULL', async () => {
+  await db.task(async (db) => {
+    await db.query(sql`SET time_zone = "+00:00";`);
+    await db.query(sql`
+      DROP TABLE IF EXISTS dates_test_timestamp_null;
+      CREATE TABLE dates_test_timestamp_null (
+        id INT NOT NULL PRIMARY KEY,
+        a TIMESTAMP NULL DEFAULT NULL
+      );
+    `);
+
+    const sampleDate = new Date('2000-06-03T05:40:10.123Z');
+    await db.query(sql`
+      INSERT INTO dates_test_timestamp_null (id, a)
+      VALUES (1, ${sampleDate}),
+             (2, NULL);
+    `);
+
+    expect(
+      (
+        await (
+          await rawConnection
+        ).query(`SELECT * from dates_test_timestamp_null`)
+      )[0],
+    ).toEqual([
+      {
+        a: '2000-06-03 15:10:10',
+        id: 1,
+      },
+      {
+        a: null,
+        id: 2,
+      },
+    ]);
+
+    const result = await db.query(sql`
+      SELECT * from dates_test_timestamp_null;
+    `);
+    expect(result).toEqual([
+      {
+        a: new Date('2000-06-03T05:40:10.000Z'),
+        id: 1,
+      },
+      {
+        a: null,
+        id: 2,
+      },
+    ]);
+  });
+});

packages/mysql/src/index.ts

@@ -300,18 +300,23 @@ function getDateParser(
       };
   }
 }
+
 function getDateTimeParser(
   mode: 'string' | 'date-object',
   timeZone: 'local' | 'utc',
-): (f: {string(): string}) => any {
+): (f: {string(): string; buffer(): Buffer}) => any {
   switch (mode) {
     case 'string':
       return (f) => f.string();
     case 'date-object':
       return (f) => {
+        const fBuffer = f.buffer();
+        if (fBuffer === null || fBuffer.length === 0) {
+          return null;
+        }
         const match =
           /^(\d{4})\-(\d{2})\-(\d{2}) (\d{2})\:(\d{2})\:(\d{2})(?:\.(\d+))?$/.exec(
-            f.string(),
+            fBuffer.toString(),
           );
         if (!match) {
           throw new Error('Expected yyyy-mm-dd HH:MM:SS');