TypeScript: Property 'propertyName' does not exist on type 'Function'

Question

TypeScript compiler is giving me an error on the following code example although the generated JavaScript on https://www.typescriptlang.org/play/ works as intended

The error is: error TS2339: Property 'tableName' does not exist on type 'Function'.

class ActiveRecord {
    static tableName(): string { // override this
        return "active_record";
    }

    static findOne(): any {
        return 'Finding a record on table: ' + this.tableName();
    }

    save(): void {
        console.log('Saving record to table: ' + this.constructor.tableName());
    }
}

class MyModel extends ActiveRecord {
    static tableName(): string {
        return "my_model";
    }
}

let x = new MyModel();
x.save(); // "Saving record on table: my_model"
console.log(MyModel.findOne()); // "Finding a record on table: my_model"

Is there is anything I can do to fix this error?

Answer 1

Replace this

this.constructor.tableName()

With this

ActiveRecord.tableName()

As a static function is must be called using the class namespace.

Answer 2

To fix the TypeScript error and still get the intended behavior (not using ActiveRecord.tableName()) you can cast the constructor to a typeof ActiveRecord

(this.constructor as typeof ActiveRecord).tableName())

Reference link: Access to static properties via this.constructor in typescript

Answer 3

One way would be to NOT use the static keyword on your properties. Otherwise use ActiveRecord.tableName()