Incorrect advisory about removing global flag with replaceAll using a RegEx

pzi · December 2, 2025, 4:47am

What language is this for?
- JavaScript
Which rule?
- typescript:S7781
Why do you believe it’s a false-positive/false-negative?
- it’s not 100% false-positive, but it’s slightly misleading as the description in the advisory states that the global flag can be removed. Which is only true if the first argument is NOT a RegEx. Otherwise the flag needs to be present to avoid a TypeError.
Are you using
- SonarQube Cloud?
  - No
- SonarQube Server / Community Build - which version?
  - Enterprise Edition v2025.5 (113872)

Advisory says

This rule flags when String#replace() is used with a global regex pattern, or when String#replaceAll() is used with a global regex flag.

…

Additionally, when String#replaceAll() is used with a regex, the global flag is redundant since the method inherently replaces all occurrences.

MDN says

If pattern is a regex, then it must have the global (g) flag set, or a TypeError is thrown.

This is also clear from looking at the linked eslint plugin rule examples.

github.com/sindresorhus/eslint-plugin-unicorn

docs/rules/prefer-string-replace-all.md

HEAD

# Prefer `String#replaceAll()` over regex searches with the global flag

💼 This rule is enabled in the following [configs](https://github.com/sindresorhus/eslint-plugin-unicorn#recommended-config): ✅ `recommended`, ☑️ `unopinionated`.

🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).

<!-- end auto-generated rule header -->
<!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->

The [`String#replaceAll()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replaceAll) method is both faster and safer as you don't have to use a regex and remember to escape it if the string is not a literal. And when used with a regex, it makes the intent clearer.

## Examples

```js
// ❌
string.replace(/RegExp with global flag/igu, '');

// ✅
string.replaceAll(/RegExp with global flag/igu, '');
```

This file has been truncated. show original

victor.diez · December 2, 2025, 1:51pm

Hello @pzi,

thanks for the feedback. We are aware the rule description is wrong and we fixed it some days ago. Next release will contain the description with the fix you mentioned.

Cheers

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Incorrect advisory about removing global flag with replaceAll using a RegEx

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