sort-comp: enforcing static lifecycle methods order

[lynxtaa]

Fixes bug: #1793

Example of incorrect code with "react/sort-comp": "error":

class Test extends React.Component {
	static getDerivedStateFromProps() {
		return null
	}

	constructor(props) {
		super(props)
		this.state = { test: 'test' }
	}

	render() {
		return this.state.test
	}
}

Example of correct code with "react/sort-comp": "error":

class Test extends React.Component {
	constructor(props) {
		super(props)
		this.state = { test: 'test' }
	}

	static getDerivedStateFromProps() {
		return null
	}

	render() {
		return this.state.test
	}
}

[dejoean]

We might want to just add indexes.length === 0 or something like that here so all named methods would be caught here rather than just getDerivedStateFromProps for future extensibility.

[lynxtaa]

Thanks, checking for indexes.length === 0 will do the job. Fixed

[ljharb]

LGTM, thanks

[ljharb]

the default parser should be sufficient here; please either add a duplicate test (one using default, one using babel-eslint) or, since this is all ES6 syntax, just have the one using the default parser.

[ThiefMaster]

Does this really make sense? Usually people group static methods together, and put them before the constructor since they are not related to a specific instance.

[ThiefMaster]

Also it's impossible to remove something from the lifecycle list without hardcoding the whole list in my config (and thus having to maintain it whenever react adds new lifecycle methods)...

[edmorley]

This appears to have caused #1821. Any ideas as to how to fix that case?

[markdemich]

The way it is now, this is requiring us to put static methods in the middle of other methods. That can't be right, can it? It's breaking all our builds.

[lynxtaa]

Static method declarations should be on top but it's not the case for getDerivedStateFromProps.

It was done that way because getDerivedStateFromProps is a lifecycle method (according to current rule description https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/sort-comp.md#rule-details).