must-call/README.md

example.on('end', mustCall(() => {})); Check the callback function is called.

must-call
==================
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`must-call` is an assertion library for async test.
This method is inspired from `node.js` project `test/common.js`.

```js
const mustCall = require('must-call');

someCallback(mustCall(() => {
  // when callback does not called at the end of the process, 
  // throw exception.
}));

somePromiseTest().then(mustCall(() => {
  // when async test does not resolved at the end of the process, 
  // throw exception.
}));
```