eslint/no-useless-constructor Suspicious

🛠️ An auto-fix is available for this rule.

What it does

Disallow constructors that can be safely removed without changing how the class works.

Why is this bad?

ES2015 provides a default class constructor if one is not specified. As such, it is unnecessary to provide an empty constructor or one that simply delegates into its parent class.

WARNING

Caveat: This lint rule will report on constructors whose sole purpose is to change visibility of a parent constructor. This is because the rule does not have type information to determine if the parent constructor is public, protected, or private.

Examples

Examples of incorrect code for this rule:

class A {
  constructor() {
  }
}

class B extends A {
  constructor(...args) {
    super(...args);
  }
}

Examples of correct code for this rule:

class A {}

class B {
  constructor() {
    doSomething();
  }
}

class C extends A {
  constructor() {
    super("foo");
  }
}

class D extends A {
  constructor() {
    super();
    doSomething();
  }
}

How to use

To enable this rule in the CLI or using the config file, you can use:

CLI

oxlint --deny no-useless-constructor

Config (.oxlintrc.json)

{
  "rules": {
    "no-useless-constructor": "error"
  }
}

References

• Rule Source