Function _assignAsyncValidators

packages/forms/src/model/abstract_model.ts:1801–1804

* Internal implementation of the `setAsyncValidators` method. Needs to be separated out into a * different method, because it is called in the constructor and it can break cases where * a control is extended.

(validators: AsyncValidatorFn | AsyncValidatorFn[] | null)

   * a control is extended.
   */
  private _assignAsyncValidators(validators: AsyncValidatorFn | AsyncValidatorFn[] | null): void {
    this._rawAsyncValidators = Array.isArray(validators) ? validators.slice() : validators;
    this._composedAsyncValidatorFn = coerceToAsyncValidator(this._rawAsyncValidators);
  }

  private _updateHasRequiredValidator(): void {
    untracked(() => this._hasRequired.set(this.hasValidator(Validators.required)));