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Rslint

    require-unicode-regexp

    Added in v0.9.1

    Configuration

    rslint.config.ts
    import { defineConfig, js } from '@rslint/core';

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'require-unicode-regexp': 'error',
    },
  },
]);

    Rule Details

    Enforces the use of the u or v flag on regular expressions.

    Examples of incorrect code for this rule:

    const a = /aaa/;
const b = /bbb/gi;
const c = new RegExp("ccc");
const d = new RegExp("ddd", "gi");

    Examples of correct code for this rule:

    const a = /aaa/u;
const b = /bbb/giu;
const c = new RegExp("ccc", "u");
const d = new RegExp("ddd", "giu");

const e = /aaa/v;
const f = /bbb/giv;
const g = new RegExp("ccc", "v");
const h = new RegExp("ddd", "giv");

// This rule ignores RegExp calls if the flags could not be evaluated to a static value.
function i(flags) {
  return new RegExp("eee", flags);
}

    Options

    This rule has one object option:

    • requireFlag: "u" or "v" — requires that particular flag instead of accepting either.

    Examples of incorrect code for this rule with { "requireFlag": "u" }:

    { "require-unicode-regexp": ["error", { "requireFlag": "u" }] }
    const foo = /foo/;
const fooRegexp = new RegExp("foo");
const bar = /bar/v;
const barRegexp = new RegExp("bar", "v");

    Examples of correct code for this rule with { "requireFlag": "u" }:

    { "require-unicode-regexp": ["error", { "requireFlag": "u" }] }
    const foo = /foo/u;
const fooRegexp = new RegExp("foo", "u");

    Examples of incorrect code for this rule with { "requireFlag": "v" }:

    { "require-unicode-regexp": ["error", { "requireFlag": "v" }] }
    const foo = /foo/;
const fooRegexp = new RegExp("foo");
const bar = /bar/u;
const barRegexp = new RegExp("bar", "u");

    Examples of correct code for this rule with { "requireFlag": "v" }:

    { "require-unicode-regexp": ["error", { "requireFlag": "v" }] }
    const foo = /foo/v;
const fooRegexp = new RegExp("foo", "v");

    Differences from ESLint

    • When flags come from a newly constructed RegExp object's property, such as RegExp("g", "u").source, rslint may skip a call that ESLint reports.
    • With computed ['__proto__'] properties in constant objects, rslint follows own-property semantics and can report a constructor call that ESLint skips.
    • Capture names or Unicode properties newer than the bundled TypeScript parser's Unicode data can receive a diagnostic without a flag suggestion.
    • For a negated v class where a range is followed by a string-valued operand, rslint omits ESLint's suggestion because JavaScript would reject the result.

    Original Documentation