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no-useless-escape false positive

See original GitHub issue

Tell us about your environment

ESLint Version: 3.9.0
Node Version: node v6.9.1
npm Version: 3.3.2

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

Please show your full configuration:

{
  "extends": ["airbnb"],
  "plugins": ["mocha", "no-unused-vars-rest"],
  "env":{
    "meteor": true,
    "es6": true,
    "commonjs": true
  },
  "parserOptions": {
    "ecmaVersion": 6,
    "sourceType": "module"
  },
  "rules": {
    "consistent-return": [0],
    "eol-last": [0],
    "eqeqeq": ["error", "smart"],
    "max-len": ["error", 150, 2],
    "no-console": [0],
    "no-mixed-requires": [0],
    "no-native-reassign": [0],
    "no-param-reassign": [0],
    "no-use-before-define" : ["error", { "functions": false }],
    "no-useless-rename": ["error", {
      "ignoreDestructuring": true
    }],
    "no-undefined": ["error"],
    "no-underscore-dangle": ["error", { "allow": ["_id"], "allowAfterThis": true }],
    "object-curly-spacing": ["error", "always", {
      "objectsInObjects": false,
      "arraysInObjects": false
    }],
    "prefer-template": [0],
    "quotes": [2, "single"],
    "radix": ["error", "always"],
    "require-yield": [0],
    "semi": [2, "always"],
    "no-unused-vars": 0,
    "import/extensions": [0],
    "react/forbid-prop-types": [0],
    "jsx-a11y/no-static-element-interactions": [0],
    "arrow-parens":[2, "as-needed"],
    "react/no-unescaped-entities": [2],
    "react/no-unused-prop-types": [2],
    "no-plusplus":[2, { "allowForLoopAfterthoughts": true }],
    "no-bitwise": [2],
    "import/no-unresolved": [2, { ignore: ['\.sol\.js$'] }],
    "class-methods-use-this": [2],
    "jsx-a11y/anchor-has-content": [2],

    /* Plugins */
    "no-unused-vars-rest/no-unused-vars": [2, { "ignoreDestructuredVarsWithRest": true }],
    "babel/generator-star-spacing": [0],
    "generator-star-spacing": [0],
    "import/no-extraneous-dependencies": [0],
    "mocha/no-exclusive-tests": "error"
  },
  "settings": {
    "import/core-modules": ["meteor"],
    "import/resolver": "meteor"
  }
}

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

const PATTERN_USERNAME = /^[a-z0-9\.\-_]+$/;

What did you expect to happen? No errors

What actually happened? Please include the actual, raw output from ESLint. error Unnecessary escape character: \. no-useless-escape

Issue Analytics

State:
Created 7 years ago
Comments:6 (3 by maintainers)

Top GitHub Comments

1reaction

thiagodelgado111commented, Oct 31, 2016

Oh, Ok! Got it! I will close the issue then, thanks a lot for helping! 😃

1reaction

not-an-aardvarkcommented, Oct 31, 2016

Right. They only need to be escaped if they appear outside of character classes (the sections surrounded by []).

var foo = /\./; // needs to be escaped
var foo = /[\.]/; // does not need to be escaped

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