`async` syntax causes `Parsing error: Unexpected token`

[zeke]

This test passes, and babel doesn't seem to have a problem with it:

const {test} = require('ava')

test('bar', async t => {
  const bar = Promise.resolve('bar')
  t.is(await bar, 'bar')
})

but standard doesn't like it:

standard: Use JavaScript Standard Style (http://standardjs.com) Try `standard --fix` to automatically fix problems.
  /Users/zeke/zeke/repos-using-electron/test/index.js:3:19: Parsing error: Unexpected token t

❯ ./node_modules/.bin/standard --version
8.0.0-beta.5

[feross]

@zeke I think you may have accidentally run a global version of standard. Can you check if standard --version is an older version?

[sotojuan]

Try doing this.

npm install --save-dev babel-eslint

Then in package.json:

 "standard": {
  "parser": "babel-eslint"
}

I'm on the AVA team and this has happened to me many times 😅

[zeke]

I'm running the local version, 8.0.0-beta.5

❯ ./node_modules/.bin/standard          
standard: Use JavaScript Standard Style (http://standardjs.com)
  /Users/zeke/zeke/repos-using-electron/test/index.js:3:19: Parsing error: Unexpected token t

❯ ./node_modules/.bin/standard --version
8.0.0-beta.5

❯ cat test/index.js                     
const {test} = require('ava')

test('bar', async t => {
  const bar = Promise.resolve('bar')
  t.is(await bar, 'bar')
})

[feross]

@zeke Try following @sotojuan's advice in an earlier comment.

You need to specify babel-eslint as your eslint parser if you want to use the async syntax. Once you do that, it'll work!

$ ./node_modules/.bin/standard --version
8.0.0-beta.5

$./node_modules/.bin/standard t.js
standard: Use JavaScript Standard Style (http://standardjs.com)
  /Users/feross/code/test/t.js:3:19: Parsing error: Unexpected token t

$ npm install babel-eslint
...

$ ./node_modules/.bin/standard --parser babel-eslint t.js

Though it's easier to use the package.json method to specifying the parser, IMO.

[zeke]

Thank you @sotojuan and @feross

[timdp]

@feross Per your recent tweet, isn't async supported out of the box with standard@8.2.0? I'm still getting errors.

[feross]

@timdp See this issue (#645)

The last release (8.2.0) added ES7 support, but async actually is part of the ES8 spec. Fortunately, we just enabled ES8 support in 8.3.0 -- released just a couple minutes ago.

Give standard 8.3.0 a shot -- should work really nicely, without the need for babel-eslint!

[timdp]

@feross That's awesome, thanks!