Error with type inference in drift 2.0

[davidmartos96]

Hello Simon, I've just updated to use drift 2.0 and I encountered with a very curious failing test in my test suite.

The following test in the integration_tests/select_integration_test.dart file fails with the following error:

Invalid argument(s): Could not find a matching SQL type for Never
DriftSqlType.forType
package:drift/…/types/mapping.dart:253
QueryRow.readNullable
package:drift/…/select/custom_select.dart:97
QueryRow.read
package:drift/…/select/custom_select.dart:82
main.getCategoryIdByDescription
test/integration_tests/select_integration_test.dart:41
===== asynchronous gap ===========================
main.<fn>

  Future<int?> getCategoryIdByDescription(TodoDb appDatabase, String description) async {
    const q = "SELECT id FROM categories WHERE desc = ?";
    final row = await appDatabase.customSelect(
      q,
      variables: [Variable<String>(description)],
    ).getSingleOrNull();
    return row?.read("id");
  }

  test('failing', () async {
    final categoryDescription = 'category description';
    await db.categories.insertOne(CategoriesCompanion.insert(description: categoryDescription));

    // Search the category we just inserted
    final categoryId = await getCategoryIdByDescription(db, categoryDescription);

    expect(categoryId != null, true);
  });

It seems to be due to the type inference in the line return row?.read("id");

If we change that into the following it works ok

final id = row?.read<int>("id");
return id;

I don't know if this is fixable in here or if it is a bug in the Dart SDK, but this wasn't failing in previous versions of drift.

Let's hope this has a solution, since this would be very hard to catch in existing code as it only fails in runtime.