useRegexLiterals

Diagnostic Category: lint/complexity/useRegexLiterals

JavaScript (and super languages)

Since: v1.3.0

Sources:

Same as: prefer-regex-literals

Description

Enforce the use of the regular expression literals instead of the RegExp constructor if possible.

There are two ways to create a regular expression:

Regular expression literals, e.g., /abc/u.
The RegExp constructor function, e.g., new RegExp("abc", "u") .

The constructor function is particularly useful when you want to dynamically generate the pattern, because it takes string arguments.

Using regular expression literals avoids some escaping required in a string literal, and are easier to analyze statically.

Examples

Invalid

new RegExp("abc", "u");

code-block.js:1:1 lint/complexity/useRegexLiterals  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ Use a regular expression literal instead of the RegExp constructor.
  
  > 1 │ new RegExp(“abc”, “u”);
      │ ^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ Regular expression literals avoid some escaping required in a string literal, and are easier to analyze statically.
  
  ℹ Safe fix: Use a literal notation instead.
  
    1   │ - new·RegExp(“abc”,·“u”);
      1 │ + /abc/u;
    2 2 │

Valid

/abc/u;

new RegExp("abc", flags);

How to configure

{
  "linter": {
    "rules": {
      "complexity": {
        "useRegexLiterals": "error"
      }
    }
  }
}