yzevm / typeorm-mock-unit-testing-example

Example how to mock TypeORM database connection for your blazing unit-tests with Mocha and Jest

TypeORM mock unit testing examples with Jest and Mocha

Example how to mock TypeORM for your blazing unit tests with Mocha and Jest. It's a simple express server

Usage

Testing

Run Mocha unit-tests

npm ci
npm run test:mocha

Run Jest unit-tests

npm run test:jest

Run e2e tests

docker-compose up -d
npm run test:e2e

Development

Run express server after changes

npm start

Build express server

npm run build

Example

Source code

class PostService {
  public getById(id: number): Promise<Post> {
    return this._findPostById(id)
  }

  private _findPostById(id: number): Promise<Post> {
    return createQueryBuilder()
      .select(['post'])
      .from(Post, 'post')
      .leftJoinAndSelect('post.images', 'image')
      .where('post.id = :id', { id })
      .orderBy({ image: 'ASC' })
      .getOne()
  }
}

Jest

describe('postService => getById', () => {
  it('getById method passed', async () => {
    typeorm.createQueryBuilder = jest.fn().mockReturnValue({
      select: jest.fn().mockReturnThis(),
      from: jest.fn().mockReturnThis(),
      leftJoinAndSelect: jest.fn().mockReturnThis(),
      where: jest.fn().mockReturnThis(),
      orderBy: jest.fn().mockReturnThis(),
      getOne: jest.fn().mockResolvedValue('0x0')
    })
    const result = await postService.getById(post.id)

    expect(result).toEqual('0x0')

    const qBuilder = typeorm.createQueryBuilder()
    expect(qBuilder.select).toHaveBeenNthCalledWith(1, ['post'])
    expect(qBuilder.from).toHaveBeenNthCalledWith(1, Post, 'post')
    expect(qBuilder.leftJoinAndSelect).toHaveBeenNthCalledWith(1, 'post.images', 'image')
    expect(qBuilder.where).toHaveBeenNthCalledWith(1, 'post.id = :id', { id: post.id })
    expect(qBuilder.orderBy).toHaveBeenNthCalledWith(1, { image: 'ASC' })
    expect(qBuilder.getOne).toHaveBeenNthCalledWith(1)
  })
})

Sinon

describe('postService => getById', () => {
  let sandbox: SinonSandbox

  beforeEach(() => {
    sandbox = createSandbox()
  })

  afterEach(() => {
    sandbox.restore()
  })

  it('getById method passed', async () => {
    const fakeQueryBuilder = createStubInstance(typeorm.SelectQueryBuilder)

    fakeQueryBuilder.select.withArgs(['post']).returnsThis()
    fakeQueryBuilder.from.withArgs(Post, 'post').returnsThis()
    fakeQueryBuilder.leftJoinAndSelect.withArgs('post.images', 'image').returnsThis()
    fakeQueryBuilder.where.withArgs('post.id = :id', { id: post.id }).returnsThis()
    fakeQueryBuilder.orderBy.withArgs({ image: 'ASC' }).returnsThis()
    fakeQueryBuilder.getOne.resolves('0x0')

    sandbox.stub(typeorm, 'createQueryBuilder').returns(fakeQueryBuilder as any)

    const result = await postService.getById(post.id)
    assert.equal(result, '0x0')
  })
})

typeorm-mock-unit-testing-example's Issues

remove "any" types

 constructor(method: string | any, fakeData: any, args?: any) {
    this.sandbox = createSandbox()

    if (args) {
      this.sandbox
        .stub(typeorm, method)
        .withArgs(args)
        .returns(fakeData)
    } else {
      this.sandbox.stub(typeorm, method).returns(fakeData)
    }
  }

It'll be better to get rid of any types

Re-write jest unit tests using native Jest mock instead of Sinon library

Motivation

It'll be useful for newcomers who wanna use Jest framework

Jest docs

Reg:Typeorm testcases

Hi @YegorZaremba ,
I am working on project with node,typeorm and my sql.I need to write unit test case for api's.we followed your sample project.But in my projects we have used query builder as follow

async checkMobilenumber(mobile:string){
     let result : any = null;
    try {
        result = await getManager()
        .getRepository(User)
        .createQueryBuilder('user')
        .where('user.mobile = :mobile')
        .setParameters({ mobile: mobile })
        .getOne();
    } catch (error) {
        logger.error('Error while execute query : ', error);
        throw error;  
    }
    return result;
};

I am requesting could you please help me how to write unit test case for above sample code.