Fixes a few false positive failures in the no-unused-prop-types rule

[EvHaus]

Fixes several false positives failures in the no-unused-prop-types rules:

• Ensures destructured props in component lifecycle methods are properly counted towards used props
• Ensure common nextProps and prevProps property names in lifecycle methods are correctly counted towards used props
• Fixes no-unused-prop-types doesn't check nextProps of componentWillReceiveProps #801

[ljharb]

can we also test all these cases with the destructuring being done inline in the signature? ie, constructor ({ something }) {?

[EvHaus]

Done!

[ljharb]

Test cases LGTM.

[yannickcr]

Merged, thanks!

[quanru]

@EvNaverniouk hi, i wonder know why must i use destructured props:
'Ensures destructured props in component lifecycle methods are properly counted towards used props'

[ljharb]

You don't have to; this just ensures it works if you do.

[quanru]

@ljharb if i don't do it in this way, it goes wrong. is this config correct ?
'no-unused-prop-types': [2, { customValidators: ['nextProps'], skipShapeProps: true }],

[ismay]

Using nextProps with an object spread operator doesn't prevent the no-unused-proptypes error (even though all props are used), I assume that's by design? (Since it's still only a proposal)

[ljharb]

The rule has no way of knowing what props you are using there because it can't know what properties are on it at runtime. Using object spread is dynamic; prefer explicit prop referencing.

[ismay]

Ah yeah of course. That makes sense.