There is no way to catch an error while in a transaction

[alextekartik]

I tried the following unit test (Added in basic_test.dart for a quick setup):

test('Catch error in transaction', () async {
  final db = await setupDatabase(path: path);
  await createTables(db);
  // Ok can catch here
  try {
    await db.getOptional('SELECT description FROM dummy1');
  } catch (_) {}
  await db.readTransaction((tx) async {
    // Not ok, cannot catch the error here
    try {
      await tx.getOptional('SELECT description FROM dummy2');
    } catch (_) {}
    await tx.getOptional('SELECT description FROM test_data');
  });
}, solo: true);

Even though I do catch the exception, the test fails.
It seems that once an error occurred there is no way to continue the transaction if we catch the exception. I guess this is by design but I think it prevents developers to catch error dynamically (such as a constraint error) while in a transaction to perform a different action in the same transaction.

[rkistner]

With SQLite, some errors can cause a transaction to be rolled back automatically. The issue is the current implementation assumes any error can cause the transaction to be rolled back, and don't allow you to continue the transaction.

I'll have to check if there's a way to determine whether or not the transaction has been rolled back. As far as I can see, the standard way to do this is using the sqlite3_get_autocommit() function, which is not exposed in the sqlite3 bindings yet.

[rkistner]

Fixed in v0.6.0