create-mockdb-repository

You can create an in-memory repository for TypeScript unit testing by implementing a MockDB repository class that uses an array to simulate a data layer. This provides fast CRUD operations and test fixtures without requiring a real database.

The best way to mock a data layer for fast prototyping is to use an in-memory MockDB repository. It simulates database interactions using an array, allowing you to perform paginated, filtered queries with sorting without the overhead of database setup.

Yes, the in-memory MockDB repository supports full CRUD operations including create, read, update, and delete. It also handles paginated, filtered queries with sorting, alongside specific methods like findAll, findById, and a clear helper with consistent timestamps.

To set up a mock repository interface for test fixtures, create a file at src/repositories/mockdb/{entity}.mockdb.repository.ts and implement the MockDb{Entity}Repository class following the reference pattern to provide consistent data access across your tests.

You should use an in-memory database over a real database when you need fast prototyping, unit tests, and test fixtures across repository interfaces. It eliminates the latency and setup requirements of a real database, accelerating development cycles.