From 08a40ba87072923693543daf71efd7008426ebc8 Mon Sep 17 00:00:00 2001
From: anna-zhernovkova <anna-zhernovkova@users.noreply.github.com>
Date: Tue, 20 Mar 2018 18:12:48 +0300
Subject: [PATCH] Prevent option change event firing when changes occur in
 component (#712) (#717)

* Prevent option change event firing when changes occur in component

* Update event lockers

* Fix typo

* Add test for bound options

* Simplify lockers

* Refactor test

* Prevent option change event firing when nested option was changed

* Move event locker to writeValue method

* Rework test

* Fix typo
---
 src/core/events-strategy.ts                   |  4 ++++
 templates/component.tst                       |  2 ++
 ...stom-value-accessor-implementation.spec.ts | 21 +++++++++++++++++++
 3 files changed, 27 insertions(+)

diff --git a/src/core/events-strategy.ts b/src/core/events-strategy.ts
index e557be18e..d2050c062 100644
--- a/src/core/events-strategy.ts
+++ b/src/core/events-strategy.ts
@@ -93,12 +93,16 @@ let createOnStableSubscription = function(ngZone: NgZone, fireNgEvent: Function)
 
 export class EmitterHelper {
     strategy: NgEventsStrategy;
+    lockedValueChangeEvent = false;
 
     constructor(ngZone: NgZone, public component: DxComponent) {
         this.strategy = new NgEventsStrategy(component, ngZone);
         createOnStableSubscription(ngZone, this.fireNgEvent);
     }
     fireNgEvent(eventName: string, eventArgs: any) {
+        if (this.lockedValueChangeEvent && eventName === 'valueChange') {
+            return;
+        }
         let emitter = this.component[eventName];
         if (emitter) {
             emitter.next(eventArgs && eventArgs[0]);
diff --git a/templates/component.tst b/templates/component.tst
index 82c2b660b..11702bb25 100644
--- a/templates/component.tst
+++ b/templates/component.tst
@@ -139,7 +139,9 @@ export class <#= it.className #>Component extends <#= baseClass #> <#? implement
     }
 <#? it.isEditor #>
     writeValue(value: any): void {
+        this.eventHelper.lockedValueChangeEvent = true;
         this.value = value;
+        this.eventHelper.lockedValueChangeEvent = false;
     }
 <#? it.widgetName !== "dxRangeSelector" #>
     setDisabledState(isDisabled: boolean): void {
diff --git a/tests/src/ui/custom-value-accessor-implementation.spec.ts b/tests/src/ui/custom-value-accessor-implementation.spec.ts
index b02981ee5..ad9bfd8f0 100644
--- a/tests/src/ui/custom-value-accessor-implementation.spec.ts
+++ b/tests/src/ui/custom-value-accessor-implementation.spec.ts
@@ -78,6 +78,7 @@ describe('DxTextBox value accessor', () => {
 
         expect(instance.option('disabled')).toBe(false);
     }));
+
     it('should change the value', async(() => {
         let fixture = TestBed.createComponent(TestContainerComponent);
         fixture.detectChanges();
@@ -89,6 +90,7 @@ describe('DxTextBox value accessor', () => {
 
         expect(instance.option('value')).toBe('text');
     }));
+
     it('should change touched option', async(() => {
         let fixture = TestBed.createComponent(TestContainerComponent);
         fixture.detectChanges();
@@ -102,4 +104,23 @@ describe('DxTextBox value accessor', () => {
 
         expect(fixture.componentInstance.formControl.touched).toBe(true);
     }));
+
+    it('should not fire valueChanges event when patchValue method is used with emitEvent=false (T614207)', () => {
+        let fixture = TestBed.createComponent(TestContainerComponent);
+        fixture.detectChanges();
+
+        let component = fixture.componentInstance,
+            form = component.form,
+            testSpy = jasmine.createSpy('testSpy');
+
+        form.valueChanges.subscribe(testSpy);
+
+        form.controls['formControl'].patchValue('text', { emitEvent: false });
+        fixture.detectChanges();
+        expect(testSpy).toHaveBeenCalledTimes(0);
+
+        form.controls['formControl'].patchValue('text2');
+        fixture.detectChanges();
+        expect(testSpy).toHaveBeenCalledTimes(1);
+    });
 });