ESLint Parsing error: Unexpected token

JavascriptReactjsEslint

Javascript Problem Overview


With this code:

import React from 'react';
import { Link } from 'react-router';
import { View, NavBar } from 'amazeui-touch';

import * as Pages from '../components';

const {  Home, ...Components } = Pages;

I get this eslint error:

7:16  error  Parsing error: Unexpected token .. Why?

Here is my eslint config:

{
  "extends": "airbnb",
  "rules": {
    /* JSX */
    "react/prop-types": [1, {
      "ignore": ["className", "children", "location", "params", "location*"]
    }],
    "no-param-reassign": [0, {
      "props": false
    }],
    "prefer-rest-params": 1,
    "arrow-body-style": 0,
    "prefer-template": 0,
    "react/prefer-stateless-function": 1,
    "react/jsx-no-bind": [0, {
      "ignoreRefs": false,
      "allowArrowFunctions": false,
      "allowBind": true
    }],
  }
}

.... .... What's the problem?

Javascript Solutions


Solution 1 - Javascript

Unexpected token errors in ESLint parsing occur due to incompatibility between your development environment and ESLint's current parsing capabilities with the ongoing changes with JavaScripts ES6~7.

Adding the "parserOptions" property to your .eslintrc is no longer enough for particular situations, such as using

static contextTypes = { ... } /* react */

in ES6 classes as ESLint is currently unable to parse it on its own. This particular situation will throw an error of:

error Parsing error: Unexpected token =

The solution is to have ESLint parsed by a compatible parser, i.e @babel/eslint-parser or babel-eslint for babel version below v7.

just add:

"parser": "@babel/eslint-parser"

to your .eslintrc file and run npm install @babel/eslint-parser --save-dev or yarn add -D @babel/eslint-parser.

Please note that as the new Context API starting from React ^16.3 has some important changes, please refer to the official guide.

Solution 2 - Javascript

ESLint 2.x experimentally supports ObjectRestSpread syntax, you can enable it by adding the following to your .eslintrc: docs

"parserOptions": {
  "ecmaVersion": 6,
  "ecmaFeatures": {
    "experimentalObjectRestSpread": true
  }
},

ESLint 1.x doesn't natively support the spread operator, one way to get around this is using the babel-eslint parser. The latest installation and usage instructions are on the project readme.

Solution 3 - Javascript

"parser": "babel-eslint" helped me to fix the issue

{
    "parser": "babel-eslint",
    "parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module",
        "ecmaFeatures": {
            "jsx": true,
            "modules": true,
            "experimentalObjectRestSpread": true
        }
    },
    "plugins": [
        "react"
    ],
    "extends": ["eslint:recommended", "plugin:react/recommended"],
    "rules": {
        "comma-dangle": 0,
        "react/jsx-uses-vars": 1,
        "react/display-name": 1,
        "no-unused-vars": "warn",
        "no-console": 1,
        "no-unexpected-multiline": "warn"
    },
    "settings": {
        "react": {
            "pragma": "React",
            "version": "15.6.1"
        }
    }
}

Reference

Solution 4 - Javascript

In my case (im using Firebase Cloud Functions) i opened .eslintrc.json and changed:

"parserOptions": {
  // Required for certain syntax usages
  "ecmaVersion": 2017
},

to:

"parserOptions": {
  // Required for certain syntax usages
  "ecmaVersion": 2020
},

Solution 5 - Javascript

I solved this issue by First, installing babel-eslint using npm

npm install babel-eslint --save-dev

Secondly, add this configuration in .eslintrc file

{
   "parser":"babel-eslint"
}

Solution 6 - Javascript

Originally, the solution was to provide the following config as object destructuring used to be an experimental feature and not supported by default:

{
  "parserOptions": {
    "ecmaFeatures": {
      "experimentalObjectRestSpread": true
    }
  }
}

Since version 5, this option has been deprecated.

Now it is enough just to declare a version of ES, which is new enough:

{
  "parserOptions": {
    "ecmaVersion": 2018
  }
}

Solution 7 - Javascript

I'm using eslint for cloud-functions (development env: flutter 2.2.3).

In my case .eslintrc.json does not exist so I had to update the .eslintrc.js file by including parserOptions: { "ecmaVersion": 2020, }, property at the end of file. My updated .eslintrc.js file looks like this:

module.exports = {
  root: true,
  env: {
    es6: true,
    node: true,
  },
  extends: [
    "eslint:recommended",
    "google",
  ],
  rules: {
    quotes: ["error", "double"],
  },
  
  // Newly added property
  parserOptions: {
    "ecmaVersion": 2020,
  },
};

Solution 8 - Javascript

Just for the record, if you are using eslint-plugin-vue, the correct place to add 'parser': 'babel-eslint' is inside parserOptions param.

  'parserOptions': {
    'parser': 'babel-eslint',
    'ecmaVersion': 2018,
    'sourceType': 'module'
  }

https://eslint.vuejs.org/user-guide/#faq

Solution 9 - Javascript

I solved this problem by setting this in .eslintrc.json file:

"extends": [
    ...,
    "plugin:prettier/recommended"
]

Solution 10 - Javascript

In febrary 2021 you can use theese values

ecmaVersion - set to 3, 5 (default), 6, 7, 8, 9, 10, 11, or 12 to specify the version of ECMAScript syntax you want to use. You can also set to 2015 (same as 6), 2016 (same as 7), 2017 (same as 8), 2018 (same as 9), 2019 (same as 10), 2020 (same as 11), or 2021 (same as 12) to use the year-based naming.

https://eslint.org/docs/user-guide/configuring/language-options#specifying-parser-options

Solution 11 - Javascript

If you have got a pre-commit task with husky running eslint, please continue reading. I tried most of the answers about parserOptions and parser values where my actual issue was about the node version I was using.

My current node version was 12.0.0, but husky was using my nvm default version somehow (even though I didn't have nvm in my system). This seems to be an issue with husky itself. So:

  1. I deleted $HOME/.nvm folder which was not deleted when I removed nvm earlier.
  2. Verified node is the latest and did proper parser options.
  3. It started working!

Solution 12 - Javascript

I was facing the issue despite implementing all the above solutions. When I downgraded the eslint version, it started working

Solution 13 - Javascript

> I'm using typescript and I solve this error change parser

....
"prettier/prettier": [
            "error",
            {
                .....
                "parser": "typescript",
                .....
            }
        ],
....

Solution 14 - Javascript

For React + Firebase Functions

Go to : functions -> .eslintrc.js

Add it - parserOptions: { ecmaVersion: 8, },

module.exports = {
  root: true,
  env: {
    es6: true,
    node: true,
  },
  parserOptions: {
    ecmaVersion: 8,
  },
  extends: ["eslint:recommended", "google"],
  rules: {
    quotes: ["error", "double"],
  },
};

Attributions

All content for this solution is sourced from the original question on Stackoverflow.

The content on this page is licensed under the Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license.

Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionDongYaoView Question on Stackoverflow
Solution 1 - JavascriptJaysQubeXonView Answer on Stackoverflow
Solution 2 - JavascriptKevan AhlquistView Answer on Stackoverflow
Solution 3 - Javascriptuser8202629View Answer on Stackoverflow
Solution 4 - JavascriptAlvin KondaView Answer on Stackoverflow
Solution 5 - JavascriptJoeeView Answer on Stackoverflow
Solution 6 - JavascriptVojtech RuzickaView Answer on Stackoverflow
Solution 7 - Javascriptsh_arkView Answer on Stackoverflow
Solution 8 - JavascriptCristianoView Answer on Stackoverflow
Solution 9 - JavascriptPazuView Answer on Stackoverflow
Solution 10 - JavascriptAlexander ShestakovView Answer on Stackoverflow
Solution 11 - JavascriptAsim K TView Answer on Stackoverflow
Solution 12 - JavascriptPravin VarmaView Answer on Stackoverflow
Solution 13 - JavascriptDálcio Macuete GarciaView Answer on Stackoverflow
Solution 14 - JavascriptPankaj KumarView Answer on Stackoverflow