https://github.com/donavon/react-proxy-hook
Helps you test a React Hook
https://github.com/donavon/react-proxy-hook
hook hooks react reactjs testing testing-tools
Last synced: 7 months ago
JSON representation
Helps you test a React Hook
- Host: GitHub
- URL: https://github.com/donavon/react-proxy-hook
- Owner: donavon
- License: mit
- Created: 2019-01-18T11:51:19.000Z (over 6 years ago)
- Default Branch: develop
- Last Pushed: 2024-02-02T15:30:35.000Z (over 1 year ago)
- Last Synced: 2024-10-12T08:11:18.824Z (12 months ago)
- Topics: hook, hooks, react, reactjs, testing, testing-tools
- Language: JavaScript
- Homepage:
- Size: 239 KB
- Stars: 5
- Watchers: 2
- Forks: 1
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# react-proxy-hook
Helps you test a React Hook
[](https://badge.fury.io/js/react-proxy-hook)
## Requirement ⚠️
To use `react-proxy-hook`, you must use `react@16.8.0-alpha.1`. React Hooks is currently at
**[RFC](https://github.com/reactjs/rfcs/pull/68)** stage.
## Installation
```bash
$ npm i -D react-proxy-hook
```
## Usage
`react-proxy-hook` is a wrapper around Kent C. Dodd's `react-testing-library`.
It was inspired by the `setup` function that Kent wrote in his
[YouTube video](https://youtu.be/0e6WCQYg5tU).
It is presented here as a simple React Hooks function wrapper.
Hooks can not be tested as standalone functions as they will not work
unless they are called from withing a rendered component.
`react-proxy-hook` gets around this limitation by proxying an actual
component.
> Maybe should have been called a HOH (Higher Order Hook)?
Look at how easy testing a Hook can be!
## Method 1: `testHook`
Method 1 requires that you place the call to your cutom Hook inside of a callback function. You then destructure (or not) your data into a `let` that you previously defined.
```js
import { testHook, cleanup } from 'react-proxy-hook';
import useCounter from '../use-counter';
afterEach(cleanup);
test('useCounter', () => {
let count, increment;
testHook(() => ({ count, increment } = useCounter({ initialCount: 2 })));
expect(count).toBe(2);
increment();
expect(count).toBe(3);
});
```
Using Method 1 (suggested), there are no restrictions on destructuring.
I've [made a PR](https://github.com/kentcdodds/react-testing-library/pull/274)
into `react-testing-library` for this, so hopefully this will be in merged soon.
See the test for Method 1 running live on CodeSandbox.
[](https://codesandbox.io/s/6lqxvx42mz?module=%2Fsrc%2F__tests__%2Fuse-counter.js)
## Method 2: `proxyHook`
You test your Hook just like you would use it in an actual component.
Just pass your actual hook to `proxyHook` and it will return
a proxied version of your hook.
```js
import { proxyHook, cleanup } from 'react-proxy-hook';
import useCounter from '../use-counter';
const useCounterProxy = proxyHook(useCounter);
afterEach(cleanup);
test('useCounter', () => {
const counterData = useCounterProxy();
counterData.increment();
expect(counterData.count).toBe(1);
counterData.decrement();
expect(counterData.count).toBe(0);
});
```
See the test for Method 2 running live on CodeSandbox.
[](https://codesandbox.io/s/6lqxvx42mz)
### Testing objects
To test with a returned object (ex: `{ foo: 'bar' }` ) use the dot notation.
```js
const returnedVal = useFooProxy();
expect(returnedVal.foo).toBe('bar');
```
### Testing arrays
To test with a returned array (ex: `[0]` ) use bracket notation.
```js
const returnedVal = useFooProxy();
expect(returnedVal[0]).toBe(0);
```
### Testing other types
To test with other returned types (i.e. string, numbers, `null`, `undefined`), use they key "value".
```js
const returnedVal = useFooProxy();
expect(returnedVal.value).toBe('foo');
```
### Limitations
You must not deconstruct the returned value in your test.
For example, the following wo't work as `count` will still be `0`.
```js
const { count, increment } = useCounterProxy(0);
increment();
expect(count).toBe(1);
```
## License
**[MIT](LICENSE)** Licensed
---
Obviously, none of this would not be possible without the tireless work of
Kent C. Dodds. Thank you! 🙏