Update: add fixer for sort-imports

[not-an-aardvark]

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

[ ] Documentation update
[ ] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[x] 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)

This adds a fixer for sort-imports.

It only sorts ImportSpecifiers, and does not sort multiple import statements. Sorting multiple import statements would cause the evaluation order of the imported files to change.

This also makes a slight change to the sort-imports rule; it reports at most one specifier from a given import statement. This allows the entire list of specifiers to be sorted as a whole. For example:

import {foo, baz, bar} from 'qux.js';

// Previously, both 'baz' and 'bar' would have been reported. Now, only 'baz' will be reported.
// However, this statement will be correctly autofixed to:

import {bar, baz, foo} from 'qux.js';

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

Nothing in particular.

[mention-bot]

@not-an-aardvark, thanks for your PR! By analyzing the history of the files in this pull request, we identified @vitorbal, @cschuller and @mysticatea to be potential reviewers.

[eslintbot]

LGTM

[nzakas]

Can you also add a test where the imported bindings have line breaks between them?

[nzakas]

I don't think we should be attempting to autofix if there are comments present. Chances are that the comments are somehow related to the bindings being imported, so keeping them in place while switching the order of the identifiers is confusing.

[eslintbot]

LGTM

[not-an-aardvark]

That's a good point about comments, I hadn't thought of that.

• Added a test with linebreaks
• Updated the fixer to not fix cases where the imported bindings have comments between them, and added tests to verify this.