Why does this trigger comma-dangle rule in eslint?

Question

This looks correct to me, but why does eslint show a rule violation, missing trailing comma comma-dangle at the end of the last property "credentials"?

  dispatch({
    type: LOGIN_USER,
    payload: credentials
  });

.eslintrc

{
  "extends": "airbnb",
  "globals": {
    "__DEV__": true
  },
  "rules": {
    "react/jsx-quotes": 0,
    "jsx-quotes": [2, "prefer-double"]
  }
}

Answer 1

I use the following combination (this works for me)

[1] .eslintrc.json

"rules": {        
        "comma-dangle": [2, "always-multiline"]         
    }

[2] JsPrettier | Prettier

"trailingComma": "all"

Results

dispatch({
  type: LOGIN_USER,
  payload: credentials,
});

Answer 2

Based on the airbnb config the rule is setup like this comma-dangle: [2, "always-multiline"].

Acoording to this, The expected code is

  dispatch({
    type: LOGIN_USER,
    payload: credentials,
  });

It expects a , at the end.

More info on rule: http://eslint.org/docs/rules/comma-dangle