salix/back/methods/image/specs/download.spec.js

const app = require('vn-loopback/server/server');

describe('image download()', () => {
    const collection = 'user';
    const size = '160x160';

    it('should return the image content-type of the user', async() => {
        const userId = 9;
        const image = await app.models.Image.download(collection, size, userId);

        expect(image[1]).toEqual('image/png');
    });

    it(`should return false if the user don't have image`, async() => {
        const userId = 8;
        const image = await app.models.Image.download(collection, size, userId);

        expect(image).toBeFalse();
    });
});