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Linting issue

See original GitHub issue

From @pronebird on February 8, 2017 12:34

Hi,

I use babel-eslint 7.1.1. and I see syntax issue with the following piece in my JSX:

<button onClick={::this.handleLogin}>Log In</button>

It points at :: and says that “expression expected”

My .eslintrc:

{
  "extends": [
    "eslint:recommended", 
    "plugin:react/recommended"
  ],
  "parser": "babel-eslint",
  "parserOptions": {
    "ecmaFeatures": {
      "jsx": true,
      "modules": true
    }
  },
  "plugins": [ "react" ], 
  "rules": {
    "indent": [ 2, 2 ],
    "quotes": [ 2, "single" ],
    "linebreak-style": [ 2, "unix" ],
    "semi": [ 2, "always" ],
    "no-console": [ 0 ],
    "no-loop-func": [ 0 ],
    "new-cap": [ 0 ],
    "no-trailing-spaces": [ 0 ],
    "no-param-reassign": [ 0 ],
    "func-names": [ 0 ],
    "comma-dangle": [ 0 ],
    "no-unused-expressions" : [ 0 ], // until fixed https://github.com/babel/babel-eslint/issues/158
    "block-scoped-var": [ 0 ], // until fixed https://github.com/eslint/eslint/issues/2253
    "react/prop-types": [ 0 ]
  },
  "env": {
    "es6": true,
    "node": true,
    "browser": true,
    "mocha": true
  }
}

ESLint works as expected and does not produce warnings:

eslint --no-ignore scripts app test *.js

Copied from original issue: Microsoft/vscode#20198

Issue Analytics

State:
Created 7 years ago
Reactions:2
Comments:9 (5 by maintainers)

Top GitHub Comments

5reactions

dmytrokyrychukcommented, May 11, 2017

I just noticed that vscode-eslint extension does not emit the “Expression expected” message!

selection_297

As a workaround I can suggest to disable JavaScript validation by putting the following into your user or workspace config:

"javascript.validate.enable": true

I think vscode uses TypeScript for JS (because the javascript.validate.enable option is listed under TypeScript section in settings). If this is true, JS validation may be enabled back once Microsoft/TypeScript/issues/3508 is resolved.

3reactions

dbaeumercommented, Mar 1, 2017

@pronebird I am able to reproduce but I have no idea why this is happening. The ESLint extension actually uses the eslint npm module to do the actual validation. I don’t know why it behaves different when running outside from the command line version inside VS Code.