noUselessEscapeInRegex

Diagnostic Category: lint/nursery/noUselessEscapeInRegex

JavaScript (and super languages)

Since: v1.9.0

Sources:

Same as: no-useless-escape

Description

Disallow unnecessary escape sequence in regular expression literals.

Escaping non-special characters in regular expression literals doesn’t have any effect. Hence, they may confuse a reader.

Examples

Invalid

/\a/;

code-block.js:1:2 lint/nursery/noUselessEscapeInRegex  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ The character doesn’t need to be escaped.
  
  > 1 │ /\a/;
      │  ^^
    2 │ 
  
  ℹ Safe fix: Unescape the character.
  
    1 │ /\a/;
      │  -

/[\-]/;

code-block.js:1:3 lint/nursery/noUselessEscapeInRegex  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ The character doesn’t need to be escaped.
  
  > 1 │ /[\-]/;
      │   ^^
    2 │ 
  
  ℹ The character should only be escaped if it appears in the middle of the character class or under the v flag.
  
  ℹ Safe fix: Unescape the character.
  
    1 │ /[\-]/;
      │   -

/[\&]/v;

code-block.js:1:3 lint/nursery/noUselessEscapeInRegex  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ The character doesn’t need to be escaped.
  
  > 1 │ /[\&]/v;
      │   ^^
    2 │ 
  
  ℹ Safe fix: Unescape the character.
  
    1 │ /[\&]/v;
      │   -

Valid

/\^\d\b/

/[\b]/

How to configure

{
  "linter": {
    "rules": {
      "nursery": {
        "noUselessEscapeInRegex": "error"
      }
    }
  }
}