Function cleanUpValidators

packages/forms/src/directives/shared.ts:224–263

(
  control: AbstractControl | null,
  dir: AbstractControlDirective,
)

 * @returns true if a control was updated as a result of this action.
 */
export function cleanUpValidators(
  control: AbstractControl | null,
  dir: AbstractControlDirective,
): boolean {
  let isControlUpdated = false;
  if (control !== null) {
    if (dir.validator !== null) {
      const validators = getControlValidators(control);
      if (Array.isArray(validators) && validators.length > 0) {
        // Filter out directive validator function.
        const updatedValidators = validators.filter((validator) => validator !== dir.validator);
        if (updatedValidators.length !== validators.length) {
          isControlUpdated = true;
          control.setValidators(updatedValidators);
        }
      }
    }

    if (dir.asyncValidator !== null) {
      const asyncValidators = getControlAsyncValidators(control);
      if (Array.isArray(asyncValidators) && asyncValidators.length > 0) {
        // Filter out directive async validator function.
        const updatedAsyncValidators = asyncValidators.filter(
          (asyncValidator) => asyncValidator !== dir.asyncValidator,
        );
        if (updatedAsyncValidators.length !== asyncValidators.length) {
          isControlUpdated = true;
          control.setAsyncValidators(updatedAsyncValidators);
        }
      }
    }
  }

  // Clear onValidatorChange callbacks by providing a noop function.
  const noop = () => {};
  registerOnValidatorChange<ValidatorFn>(dir._rawValidators, noop);
  registerOnValidatorChange<AsyncValidatorFn>(dir._rawAsyncValidators, noop);

  return isControlUpdated;
}

function setUpViewChangePipeline(control: FormControl, dir: NgControl): void {
  dir.valueAccessor!.registerOnChange((newValue: any) => {