Testing

The package provides two testing helpers:

• DrizzleTestModule registers a client under the same DI tokens as DrizzleModule.
• createDrizzleMockClient() and createDrizzleRepositoryMock() create simple, typed object mocks.

Unit Tests

Use mocks when you want to isolate a service from SQL behavior.

import { Test } from '@nestjs/testing';
import {
  DrizzleTestModule,
  createDrizzleMockClient,
} from 'nest-drizzle-native';

const db = createDrizzleMockClient({
  query: {
    users: {
      findMany: () => [{ id: 'user_1', name: 'Ada' }],
    },
  },
});

const moduleRef = await Test.createTestingModule({
  imports: [DrizzleTestModule.forRoot({ client: db })],
  providers: [UsersService],
}).compile();

This is useful for fast service tests, but it is intentionally shallow. It does not prove SQL syntax, schema mapping, driver behavior, or transaction behavior.

Repository Tests

Use repository mocks when a service depends on a repository and the repository has its own focused tests.

const usersRepository = createDrizzleRepositoryMock<UsersRepository>({
  findById: async id => ({ id, name: 'Ada' }),
});

Integration Tests

Use a real Drizzle client when the behavior being tested depends on the database:

• query shape and selected columns
• migrations or table setup
• inserts, updates, deletes, and ordering
• transaction commit and rollback
• driver-specific behavior

The package test suite includes real driver integration coverage for libSQL, better-sqlite3, PostgreSQL, and MySQL. The CI suite runs PostgreSQL and MySQL through service containers, while local runs skip those two unless connection URLs are provided.

The focused samples use the same philosophy: run real Nest modules against local database files when behavior depends on Drizzle, drivers, or transactions.

Local Commands

npm run test
npm run test:cov
npm run ci

npm run test:cov writes coverage/coverage-summary.json and test-results.json, which are used by the GitHub coverage and performance comments.