import sinon from 'sinon'; import expect from 'app/test/unexpected'; import PromiseMiddlewareLayer from 'app/services/request/PromiseMiddlewareLayer'; describe('PromiseMiddlewareLayer', () => { describe('#add()', () => { let layer; beforeEach(() => { layer = new PromiseMiddlewareLayer(); }); it('should have no middlewares by default', () => { expect(layer.middlewares, 'to have length', 0); }); it('should add middleware into layer', () => { layer.add({}); expect(layer.middlewares, 'to have length', 1); }); it('throws if middleware is not object', () => { expect(() => layer.add(1), 'to throw', 'A middleware must be an object'); }); }); describe('#run()', () => { it('should return promise', () => { const layer: any = new PromiseMiddlewareLayer(); expect(layer.run('then'), 'to be a', Promise); }); testAction('then'); testAction('catch'); function testAction(name) { describe(`run('${name}')`, () => { it('should run middleware', () => { const layer: any = new PromiseMiddlewareLayer(); const middleware = { [name]: sinon .spy(() => Promise.resolve()) .named(`middleware.${name}`), }; layer.add(middleware); return layer.run(name).then(() => { expect(middleware[name], 'was called once'); }); }); it('should pass data', () => { const layer: any = new PromiseMiddlewareLayer(); const middleware = { [name]: sinon .spy(() => Promise.resolve()) .named(`middleware.${name}`), }; const data = {}; layer.add(middleware); return layer.run(name, data).then(() => { expect(middleware[name], 'to have a call satisfying', [data]); }); }); it('should call multiple middlewares', async () => { const layer: any = new PromiseMiddlewareLayer(); const initialValue = 'initialValue'; const options = { foo: 'bar' }; const firstMethod = name === 'catch' ? 'reject' : 'resolve'; const middleware1 = { [name]: sinon .spy(() => (Promise[firstMethod] as any)('new data')) .named(`middleware1.${name}`), }; const middleware2 = { [name]: sinon .spy(() => Promise.resolve('the last data')) .named(`middleware2.${name}`), }; layer.add(middleware1); layer.add(middleware2); const resp = await layer.run(name, initialValue, options); expect(middleware1[name], 'to have a call satisfying', [ initialValue, options, ]); expect(middleware2[name], 'to have a call satisfying', [ 'new data', options, ]); expect(resp, 'to equal', 'the last data'); }); }); } it('should not call wrong actions', () => { const layer: any = new PromiseMiddlewareLayer(); const middleware = { then: () => {}, wrongAction: sinon .spy(() => Promise.resolve()) .named('middleware.wrongAction'), }; layer.add(middleware as any); return layer.run('then').then(() => { expect(middleware.wrongAction, 'was not called'); }); }); it('should not call next catch middleware if previous was resolved', () => { const layer: any = new PromiseMiddlewareLayer(); const middleware1 = { catch: () => Promise.resolve(), }; const middleware2 = { catch: sinon.spy(() => {}).named('middleware2.catch'), }; layer.add(middleware1); layer.add(middleware2); return layer.run('catch').then(() => { expect(middleware2.catch, 'was not called'); }); }); it('should pass restart callback if any', () => { const layer: any = new PromiseMiddlewareLayer(); const middleware = { catch: sinon.spy(() => Promise.resolve()).named('middleware.catch'), }; const callback = async () => {}; layer.add(middleware); return layer.run('catch', {}, {}, callback).then(() => { expect(middleware.catch, 'to have a call satisfying', [ {}, {}, expect.it('to be', callback), ]); }); }); }); });