feat: add hasError helper

apps/example/src/app/simple-form/simple-form.component.ts

@@ -27,6 +27,12 @@ import { CustomErrorComponent } from '../custom-input-error.component';
  [debounce]="700"
  [formField]="form.controls.username"
  />
+ @if(form.controls.username.hasError('required')) {
+ <small>
+ Username is required
+ </small>
+ }
+
  </div>
 
  <div>

packages/platform/src/lib/form-field.ts

@@ -38,6 +38,7 @@ export type FormField<Value = unknown> = {
  markAsTouched: () => void;
  markAsDirty: () => void;
  reset: () => void;
+ hasError: (errorKey: string) => boolean;
  registerOnReset: (fn: (value: Value) => void) => void;
 };
 
@@ -136,6 +137,7 @@ export function createFormField<Value>(
  disabled: disabledSignal,
  markAsTouched: () => touchedStateSignal.set('TOUCHED'),
  markAsDirty: () => dirtyStateSignal.set('DIRTY'),
+ hasError: (errorKey: string) => !!errorsSignal()[errorKey],
  registerOnReset: (fn: (value: Value) => void) => (onReset = fn),
  reset: () => {
  valueSignal.set(defaultValue);

packages/platform/src/lib/form-group.ts

@@ -36,6 +36,7 @@ export type FormGroup<Fields extends FormGroupCreatorOrSignal = {}> = {
  touched: Signal<boolean>;
  errors: Signal<{}>;
  errorsArray: Signal<InvalidDetails[]>;
+ hasError: (errorKey: string) => boolean;
  markAllAsTouched: () => void;
  reset: () => void;
 };
@@ -172,6 +173,7 @@ export function createFormGroup<FormFields extends FormGroupCreator>(
  });
  return myErrors.concat(...childErrors);
  }),
+ hasError: (errorKey: string) => !!errorsSignal()[errorKey],
  dirtyState: dirtyStateSignal,
  dirty: dirtySignal,
  touchedState: touchedStateSignal,

packages/platform/src/lib/validation.ts

@@ -91,7 +91,7 @@ export function computeValidateState(
  return computed(() => validateSignal().map((v) => v()));
 }
 
-export function computeErrors(validateSignal: Signal<ValidateState[]>) {
+export function computeErrors(validateSignal: Signal<ValidateState[]>): Signal<Record<string, ValidationError>> {
  return computed(() => {
  return validateSignal().reduce((acc, errors) => {
  if (!errors.errors) {