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comma-dangle = always-multiline and the spread operator

See original GitHub issue

There is a bit of an issue with comma-dangle set to "always-multiline" and the spread operator used in a destructuring assignment:

var [
  x,
  y,
  ...data // Getting "missing trailing comma" error
] = parsed;

For compliance with spec there should be no comma after the AssignmentRestElement and I think that "always-multiline" should treat this as a special case and ignore the missing trailing comma.

For now I’m ignoring the error for this line.

The version I have is 1.2.1.

Issue Analytics

State:
Created 8 years ago
Comments:11 (8 by maintainers)

Top GitHub Comments

2reactions

not-an-aardvarkcommented, Dec 11, 2017

I feel like this case is fundamentally the parser’s job to handle. It seems strange for us to add logic for a new error message just to account for a bug in babel-eslint.

Updating the documentation sounds good to me, though.

2reactions

fatfiszcommented, Dec 11, 2017

Wouldn’t a better error message be a good solution here?

Unexpected trailing comma - no comma allowed after rest properties.

If so, then I could do that.

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