Cannot query on dates using Generated<Timestamp>

[jvandenaardweg]

When upgrading prisma-kysely from 1.3.0 to 1.4.0 I noticed the Generated type changed by using the one provided by kysely

This has the side effect that you now cannot query on fields that have this Generated<Timestamp> type:

const example = await kysely
    .selectFrom('Example')
    .where('createdAt', '>=', start)
    .where('createdAt', '<=', end)
    .executeTakeFirst();

// TS error on .where('createdAt'):
// Argument of type 'Date | null' is not assignable to parameter of type 'OperandValueExpressionOrList<DB, "Example", "createdAt">'.

Above query worked fine, without TS errors, before upgrading.

This is a simplified version of how it currently generates the types:

import type { ColumnType, Generated, GeneratedAlways } from 'kysely';
export type Timestamp = ColumnType<Date, Date | string, Date | string>;

export type Example = {
  id: GeneratedAlways<number>;
  name: string;
  createdAt: Generated<Timestamp>;
  updatedAt: Generated<Timestamp>;
};

The Timestamp type is using ColumnType. According to the Kysely maintainer, you should not use Generated when also using ColumnType: kysely-org/kysely#452 (comment)

So when I manually change the type to the following, it works without errors:

import type { ColumnType, Generated, GeneratedAlways } from 'kysely';
export type Timestamp = ColumnType<Date, Date | string, Date | string>;

export type Example = {
  id: GeneratedAlways<number>;
  name: string;
  createdAt: Timestamp; // Removed Generated type
  updatedAt: Generated<Timestamp>;
};

But this has the side-effect that it now expects a createdAt field to be present on inserts -_-

This is a simplified version of my Prisma schema:

model Example {
  id            Int       @id @default(autoincrement()) @db.UnsignedInt
  name          String
  createdAt     DateTime  @default(now())
  updatedAt     DateTime @default(dbgenerated("CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3)"))
}

So i'm not really sure on what the solution here is

This is how the generated types file looked like before and worked fine, both on selects and inserts:

import type { ColumnType } from 'kysely';
export type Generated<T> = T extends ColumnType<infer S, infer I, infer U>
  ? ColumnType<S, I | undefined, U>
  : ColumnType<T, T | undefined, T>;
export type Timestamp = ColumnType<Date, Date | string, Date | string>;

export type Example = {
  id: Generated<number>;
  name: string;
  createdAt: Generated<Timestamp>;
  updatedAt: Generated<Timestamp>;
};

So maybe this should be restored?

[valtyr]

Oops, I thought I was cleaning things up but created a regression. Sorry about that. PR on the way.