src/internal/bind-this-to-member-functions.ts


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/**
 * Bind all functions of the given instance to itself so you can use them independently.
 *
 * @internal
 *
 * @param instance The class instance of which the methods are to be bound to itself.
 *
 * @example
 * const someModule = new SomeModule(faker);
 * bindThisToMemberFunctions(someModule); // Usually called inside the constructor passing `this`
 * const someMethod = someModule.someMethod;
 * someMethod(); // Works
 */
// eslint-disable-next-line @typescript-eslint/no-explicit-any
export function bindThisToMemberFunctions<TClass extends { new (): any }>(
  instance: InstanceType<TClass>
): void {
  let p = Object.getPrototypeOf(instance);
  do {
    for (const name of Object.getOwnPropertyNames(p)) {
      if (typeof instance[name] === 'function' && name !== 'constructor') {
        instance[name] = instance[name].bind(instance);
      }
    }

    p = Object.getPrototypeOf(p);
  } while (p !== Object.prototype);
}