prefer-regexp-exec

Enforce RegExp#exec over String#match if no global flag is provided.

As String#match is defined to be the same as RegExp#exec when the regular expression does not include the g flag, prefer a consistent usage.

Attributes

• Included in configs
  • ✅ Recommended
  • 🔒 Strict
• Fixable
  • 🔧 Automated Fixer
  • 💡 Suggestion Fixer
• 💭 Requires type information

Rule Details

This rule is aimed at enforcing a consistent way to apply regular expressions to strings.

From String#match on MDN:

If the regular expression does not include the g flag, returns the same result as RegExp.exec().

RegExp#exec may also be slightly faster than String#match; this is the reason to choose it as the preferred usage.

Examples of code for this rule:

❌ Incorrect

'something'.match(/thing/);

'some things are just things'.match(/thing/);

const text = 'something';
const search = /thing/;
text.match(search);

✅ Correct

/thing/.exec('something');

'some things are just things'.match(/thing/g);

const text = 'something';
const search = /thing/;
search.exec(text);

Options

.eslintrc.cjs

module.exports = {
  "rules": {
    "@typescript-eslint/prefer-regexp-exec": "warn"
  }
};

This rule is not configurable.

When Not To Use It

If you prefer consistent use of String#match for both, with g flag and without it, you can turn this rule off.

Resources

• Rule source
• Test source