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no-misused-new

Enforce valid definition of new and constructor.

✅

Extending "plugin:@typescript-eslint/recommended" in an ESLint configuration enables this rule.

JavaScript classes may define a constructor method that runs when a class instance is newly created. TypeScript allows interfaces that describe a static class object to define a new() method (though this is rarely used in real world code). Developers new to JavaScript classes and/or TypeScript interfaces may sometimes confuse when to use constructor or new.

This rule reports when a class defines a method named new or an interface defines a method named constructor.

.eslintrc.cjs
module.exports = {
  "rules": {
    "@typescript-eslint/no-misused-new": "error"
  }
};

Try this rule in the playground ↗

Examples​

declare class C {
  new(): C;
}

interface I {
  new (): I;
  constructor(): void;
}
Open in Playground

Options​

This rule is not configurable.

When Not To Use It​

If you intentionally want a class with a new method, and you're confident nobody working in your code will mistake it with a constructor, you might not want this rule. You might consider using ESLint disable comments for those specific situations instead of completely disabling this rule.

Resources​