test-helpers

Some small and simple helpers for my unit tests

Content

DispatchMock

How to use

import { DispatchMock } from "luispablo-test-helpers";

...

const expectedActions = [{ type: "set item", payload: "some text" }, { type: "remove item" }];
const dispatch = DispatchMock(assert, expectedActions, true);

The first param (assert) is the tape assert object. The expected actions is and array of objects, each one containing a type and a payload. As you can see the payload is optional, but the type is required. For each action called it will check that a part of the action type has the type you provided in them and, if it matches and it has a payload, checks for a === of the action payload to the expected one.

The last param set wether to log via assert.comment the triggered action or not (if it's not provided it wont log)

FetcherMock

This component is a function that works as the new fetch API function, so when your code calls it as fetcher("url") it will return a promise that resolves or reject, based on the params you provide. So, first do

import { FetcherMock } from "luispablo-test-helpers";

And then, for an HTTP 200 response with a JSON body do

const fetcher = FetcherMock({ json: { name: "Tom" } });

So, fetch("anyURL") will resolve a response with a json() function that returns { name: "Tom" }. Or, the same but with text:

const fetcher = FetcherMock({ text: { "some dummy text" } });

This will resolve a response with a text() function that returns "some dummy text".

To resolve the promise, but with different HTTP code do

const fetcher = FetcherMock({ status: 404 });

This will still resolve when you invoke it, but giving you a response object with the status property in 404.

And finally, if you want it to reject (as in a network error) do

const fetcher = FetcherMock({ error: { code: 1, message: "Network error" } });

This will fall into the catch part of the promise, with an error param with code 1 and the message shown above.

Data stored by the FetcherMock

The mocked fetcher receives a URL and, optionally, some options (like method, headers, body, and so on). It saves the URL and the options in its invokedURL and providedOptions properties.

var fetcher = FetcherMock();

// your code here, and later you can do

console.log(fetcher.invokedURL); // This should give you the actual URL invoked
console.log(fetcher.providedOptions); // Here you get the second param given to fetch

If you want to see al available options check https://github.com/github/fetch

LocalStorageMock

This is a HTML 5 window local storage mock, to use in your tests. Just do:

import { LocalStorageMock } from "luispablo-test-helpers";

...

// and then
const storage = LocalStorageMock();
// and you're done!