getter-return

A getter that doesn't return gives undefined to any code that reads the property. Usually someone forgot the return, or one branch of the getter doesn't have one.

The rule checks get in classes and object literals, and the get function of a property descriptor passed to Object.defineProperty, Reflect.defineProperty, Object.defineProperties or Object.create.

This rule is on by default in JavaScript files. It's off in TypeScript files, where TypeScript reports the same mistake.

Configure

On by default as an error. To turn it off:

[lint.rules]
"getter-return" = "off" # or "warn"

Every option, set to its default:

[lint.rules]
"getter-return" = ["error", {
  allowImplicit = false,
}]

Examples

Reported:

const user = {
  get fullName() {
    `${this.first} ${this.last}`;
  },
};

class Cart {
  get total() {
    if (this.items.length > 0) {
      return sum(this.items);
    }
  }
}

Object.defineProperty(user, "age", {
  get: function () {
    now() - this.born;
  },
});

Not reported:

const user = {
  get fullName() {
    return `${this.first} ${this.last}`;
  },
};

class Cart {
  get total() {
    if (this.items.length > 0) {
      return sum(this.items);
    }
    return 0;
  }
}

Options

Option	Default	What it does
allowImplicit	false	Allow return; without a value. The getter still needs to end with a return on every path.

class Session {
  get token() {
    return;
  }
}

class Session {
  get token() {
    return;
  }
}