template-curly-spacing does not always work with babel-eslint

Tell us about your environment

macOS Sierra, iTerm 2.0

• ESLint Version: 3.12.2
• Node Version: 5.1.0
• npm Version: 3.3.12

What parser (default, Babel-ESLint, etc.) are you using?

babel-eslint

Please show your full configuration:

{
  "parser": "babel-eslint"
  "rules": {
    "template-curly-spacing": ["error", "never"]
  }
}

What did you do? Please include the actual source code causing the issue.

See demo repo here.

`a${(function() { return `b${ 0 }c`; })}d`;

What did you expect to happen?

I expect two errors, one on both sides of the 0 inside the nested template literal.

What actually happened? Please include the actual, raw output from ESLint.

I got one error:

/Users/donovan/Desktop/eslint-babel-template-curly-issue/index.js
  1:33  error  Unexpected space(s) before '}'  template-curly-spacing

✖ 1 problem (1 error, 0 warnings)

eslint it not reporting the space after ${ as a problem. This is due to the difference in tokens between espree and babylon. It may actually be a bug in babylon, but I’m not sure. See the demo repo for further analysis.

[vitorbal]

@eventualbuddha looks like that issue was an exception, as can be seen in the discussion here: https://github.com/eslint/eslint/issues/6266#issuecomment-222560132 As a rule of thumb, if the buggy behavior happens with babel-eslint but not with the default parser, then you should report an issue in the babel-eslint repo.

[eventualbuddha]

One final note, I saw that https://github.com/eslint/eslint/pull/6290 was created to fix an issue with babel-eslint so I decided that it might be worth opening here. Is there guidance somewhere on which repo to open an issue in?