object-curly-spacing false-positive with es6 import with trailing comma

[leebyron]

version: 1.0.0

import {
  A,
  B,
} from 'module';

with rule:

"object-curly-spacing": [2, "always"]

reports:

3:4   error  A space is required before ','  object-curly-spacing

But I expected no error.

[eslintbot]

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[xjamundx]

I'll look at this today..

[xjamundx]

Weird I'm getting:

  1 failing

  1) object-curly-spacing import {
    A,
    B,
} from 'module';;:
     AssertionError: Should have no errors but had 1: [ { fatal: true,
    severity: 2,
    message: 'Unexpected token }',
    line: 4,
    column: 2 } ]
      at testValidTemplate (/Users/jamuferguson/dev/eslint/lib/testers/rule-tester.js:9:5044)
      at Context.<anonymous> (/Users/jamuferguson/dev/eslint/lib/testers/rule-tester.js:9:7934)
      at callFn (/Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runnable.js:251:21)
      at Test.Runnable.run (/Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runnable.js:244:7)
      at Runner.runTest (/Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runner.js:374:10)
      at /Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runner.js:452:12
      at next (/Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runner.js:299:14)
      at /Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runner.js:309:7
      at next (/Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runner.js:248:23)
      at Immediate._onImmediate (/Users/jamuferguson/dev/eslint/node_modules/mocha/lib/runner.js:276:5)
      at processImmediate [as _immediateCallback] (timers.js:367:17)

With espree 2.2.0 and eslint 1.1.0.

Are you using babel-eslint? There may be a bug in espree assuming trailing commas are allowed there...

Interestingly enough this seems to work alright:
require('espree').parse("var { A, B, } = require('module');", {ecmaFeatures: {modules: true, destructuring: true}}) (at least the parsing part...will get back on the issue at hand)

[xjamundx]

1. @leebyron I think this may be a babel-eslint issue in the way it's handing column numbers or something?
2. The destructuring trailing-comma case works as expected with eslint (though it wasn't being tested)
3. Espree currently does not support trailing commas in import and ... oh wait. it looks like I was supposed to fix that last month Support for trailing commas in Import/Export statements js#148

[leebyron]

Yes, I'm using the babel-eslint parser. cc @hzoo

[hzoo]

Ok since @xjamundx has a PR eslint/js#186 think this might be fixed eslint side?

[hzoo]

Ok made a PR to fix after eslint/js#186

[xjamundx]

Awesome!