Update: check renaming identifier in object destructuring (fixes 12827)

[yeonjuan]

Prerequisites checklist

• I have read the contributing guidelines.
• The team has reached consensus on the changes proposed in this pull request. If not, I understand that the evaluation process will begin with this pull request and won't be merged until the team has reached consensus.

What is the purpose of this pull request? (put an "X" next to an item)

[x] Documentation update
[x] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[ ] Add autofixing to a rule
[ ] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

What changes did you make? (Give an overview)

const { renamed: renaming} = foo;

Changed this rule to warn the length of the renaming identifier rather than a renamed identifier.

Is there anything you'd like reviewers to focus on?

Fixes #12827

[mdjermanovic]

@yeonjuan sorry for the confusion, I didn't mean to suggest to fix these 3 issues now.

Since you already fixed that, I think that 2 of those 3 changes are certainly correct at this moment.

var {x} = foo; might need a discussion as it could be undesirable for some users.

I left comments on tests cases for these 3 changes.

[mdjermanovic]

Checked examples from the docs:

• var { a: [x]} = {}; examples will be valid after this PR (without the other PR), maybe we should remove them from invalid sections, in this PR.
• var { prop: a } = {}; in section Examples of incorrect code for this rule with the { "min": 4 } option: is now invalid.
• In the same section, var foo = function (event) { /* do stuff */ }; is also invalid. that was probably a mistake in the docs.
• In the same section, obj.element = document.body; and ({ prop: obj.name } = {}); are both invalid on obj. That was probably broken in the code. Not sure what should we do with this, maybe leave for another PR.

[mdjermanovic]

LGTM, thanks!

[kaicataldo]

Is this a regression in this PR? I see that this is going to be worked on in a separate PR. Do we have an issue outlining our plan for this (just in case someone else needs to pick this work up)?

[yeonjuan]

@kaicataldo

Is this a regression in this PR?

Yes. The case will not be warned after this PR merged because the actual version warns about a rather than x.

• Online Demo

/*eslint id-length: ["error", { "min": 4 }]*/
/*eslint-env es6*/

var { a: [x]} = {}; // Error: Identifier name `a` ...

And there is a PR working on to fix it (#12839).

Do we have an issue outlining our plan for this (just in case someone else needs to pick this work up)?

I will add an outlining plan for this on #12832. Thanks 👍

[kaicataldo]

Thanks for working on this!

[kaicataldo]

Thanks for contributing!