From c628840721ef1c644539bdd912d1f70c9aea2480 Mon Sep 17 00:00:00 2001
From: Tim Deschryver <28659384+timdeschryver@users.noreply.github.com>
Date: Wed, 7 Feb 2024 22:09:18 +0100
Subject: [PATCH] fix: ignore initial value to set dirty state

---
 apps/example/src/app/basic-form/basic-form.component.ts | 7 +++++--
 packages/platform/src/lib/form-field.ts                 | 5 ++++-
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/apps/example/src/app/basic-form/basic-form.component.ts b/apps/example/src/app/basic-form/basic-form.component.ts
index 139ee7f..e0997cf 100644
--- a/apps/example/src/app/basic-form/basic-form.component.ts
+++ b/apps/example/src/app/basic-form/basic-form.component.ts
@@ -28,6 +28,7 @@ import { CustomErrorComponent } from '../custom-input-error.component';
 
       <div>
         <button (click)="reset()">Reset form</button>
+        <button (click)="prefill()">Prefill form</button>
 
         <h3>States</h3>
         <pre
@@ -85,7 +86,9 @@ export default class BasicFormComponent {
     this.form.reset();
   }
 
-  setForm() {
-    // TODO: allow form values to be set
+  prefill() {
+    // TODO: improve this API to set form groups
+    this.form.controls.age.value.set(42);
+    this.form.controls.name.value.set('Bob');
   }
 }
diff --git a/packages/platform/src/lib/form-field.ts b/packages/platform/src/lib/form-field.ts
index 29109c6..d87e379 100644
--- a/packages/platform/src/lib/form-field.ts
+++ b/packages/platform/src/lib/form-field.ts
@@ -86,11 +86,14 @@ export function createFormField<Value>(
   const disabledSignal = signal(false);
   const readOnlySignal = signal(false);
 
+  let previousValue: unknown|undefined = undefined;
   effect(
     () => {
-      if (valueSignal()) {
+      const newValue = valueSignal();
+      if (previousValue !== undefined && newValue !== previousValue) {
         dirtyStateSignal.set('DIRTY');
       }
+      previousValue = newValue;
     },
     {
       allowSignalWrites: true,