E.g. I have a problem when some endpoints are down or causing errors, but I still need to develop. I have something like UserService.getUsers I am aware of mocking functions in jest and so on, but I have no idea how I'd better get fake data which I can specify myself.
I thought about a HOC, which redefines functions I need to mock like
UserService.getUsers=Promise.resolve({});
But I don't think this is the best way to do this
NOTE: That's not related to testing stuff
If you're using Webpack, you could use the resolve property of the Webpack configuration to alias your imports to some local mocked version.
https://webpack.js.org/configuration/resolve/
For example, if you had some import like this:
import UserService from 'some-package-or-path';
const myData = UserService.getUsers();
You can alias some-package-or-path to a local file:
// webpack.config.js
const path = require('path');
module.exports = {
//...
resolve: {
alias: {
'some-package-or-path': path.resolve(__dirname, 'src/mocks/userServiceMock'),
},
},
};
// userServiceMock index.js
const mock = {
getUserData: () => {
return {
mockedDataProperties: 'whatever'
}
}
};
export default mock;
Obviously your implementation will differ a bit but that's the gist of it.