From 9971faa7d9c54db40c19fa6333dce8a65d38ccd4 Mon Sep 17 00:00:00 2001
From: Artur Androsovych <arthurandrosovich@gmail.com>
Date: Thu, 13 Jan 2022 13:23:37 +0200
Subject: [PATCH] perf(module:input-number): reduce change detection cycles
 (#7129)

---
 .../input-number/input-number.component.ts    | 56 ++++++++++++-------
 components/input-number/input-number.spec.ts  | 35 +++++++++++-
 2 files changed, 70 insertions(+), 21 deletions(-)

diff --git a/components/input-number/input-number.component.ts b/components/input-number/input-number.component.ts
index 7cf09aa2a3..f15665e01f 100644
--- a/components/input-number/input-number.component.ts
+++ b/components/input-number/input-number.component.ts
@@ -15,6 +15,7 @@ import {
   EventEmitter,
   forwardRef,
   Input,
+  NgZone,
   OnChanges,
   OnDestroy,
   OnInit,
@@ -25,7 +26,7 @@ import {
   ViewEncapsulation
 } from '@angular/core';
 import { ControlValueAccessor, NG_VALUE_ACCESSOR } from '@angular/forms';
-import { Subject } from 'rxjs';
+import { fromEvent, Subject } from 'rxjs';
 import { takeUntil } from 'rxjs/operators';
 
 import { BooleanInput, NzSizeLDSType, OnChangeType, OnTouchedType } from 'ng-zorro-antd/core/types';
@@ -70,8 +71,6 @@ import { InputBoolean, isNotNil } from 'ng-zorro-antd/core/util';
         [placeholder]="nzPlaceHolder"
         [attr.step]="nzStep"
         [attr.inputmode]="nzInputMode"
-        (keydown)="onKeyDown($event)"
-        (keyup)="stop()"
         [ngModel]="displayValue"
         (ngModelChange)="onModelChange($event)"
       />
@@ -336,20 +335,6 @@ export class NzInputNumberComponent implements ControlValueAccessor, AfterViewIn
     this.inputElement.nativeElement.value = `${displayValue}`;
   }
 
-  onKeyDown(e: KeyboardEvent): void {
-    if (e.keyCode === UP_ARROW) {
-      const ratio = this.getRatio(e);
-      this.up(e, ratio);
-      this.stop();
-    } else if (e.keyCode === DOWN_ARROW) {
-      const ratio = this.getRatio(e);
-      this.down(e, ratio);
-      this.stop();
-    } else if (e.keyCode === ENTER) {
-      this.updateDisplayValue(this.value!);
-    }
-  }
-
   writeValue(value: number): void {
     this.value = value;
     this.setValue(value);
@@ -379,7 +364,8 @@ export class NzInputNumberComponent implements ControlValueAccessor, AfterViewIn
   }
 
   constructor(
-    private elementRef: ElementRef,
+    private ngZone: NgZone,
+    private elementRef: ElementRef<HTMLElement>,
     private cdr: ChangeDetectorRef,
     private focusMonitor: FocusMonitor,
     @Optional() private directionality: Directionality
@@ -402,9 +388,41 @@ export class NzInputNumberComponent implements ControlValueAccessor, AfterViewIn
       });
 
     this.dir = this.directionality.value;
-    this.directionality.change?.pipe(takeUntil(this.destroy$)).subscribe((direction: Direction) => {
+    this.directionality.change.pipe(takeUntil(this.destroy$)).subscribe((direction: Direction) => {
       this.dir = direction;
     });
+
+    this.ngZone.runOutsideAngular(() => {
+      fromEvent(this.inputElement.nativeElement, 'keyup')
+        .pipe(takeUntil(this.destroy$))
+        .subscribe(() => this.stop());
+
+      fromEvent<KeyboardEvent>(this.inputElement.nativeElement, 'keydown')
+        .pipe(takeUntil(this.destroy$))
+        .subscribe(event => {
+          const { keyCode } = event;
+
+          if (keyCode !== UP_ARROW && keyCode !== DOWN_ARROW && keyCode !== ENTER) {
+            return;
+          }
+
+          this.ngZone.run(() => {
+            if (keyCode === UP_ARROW) {
+              const ratio = this.getRatio(event);
+              this.up(event, ratio);
+              this.stop();
+            } else if (keyCode === DOWN_ARROW) {
+              const ratio = this.getRatio(event);
+              this.down(event, ratio);
+              this.stop();
+            } else {
+              this.updateDisplayValue(this.value!);
+            }
+
+            this.cdr.markForCheck();
+          });
+        });
+    });
   }
 
   ngOnChanges(changes: SimpleChanges): void {
diff --git a/components/input-number/input-number.spec.ts b/components/input-number/input-number.spec.ts
index b8d159dace..d916129557 100644
--- a/components/input-number/input-number.spec.ts
+++ b/components/input-number/input-number.spec.ts
@@ -1,8 +1,9 @@
-import { DOWN_ARROW, UP_ARROW } from '@angular/cdk/keycodes';
-import { Component, DebugElement, ViewChild } from '@angular/core';
+import { DOWN_ARROW, ENTER, TAB, UP_ARROW } from '@angular/cdk/keycodes';
+import { ApplicationRef, Component, DebugElement, NgZone, ViewChild } from '@angular/core';
 import { ComponentFixture, fakeAsync, flush, TestBed, tick } from '@angular/core/testing';
 import { FormBuilder, FormGroup, FormsModule, ReactiveFormsModule } from '@angular/forms';
 import { By } from '@angular/platform-browser';
+import { take } from 'rxjs/operators';
 
 import { createKeyboardEvent, dispatchEvent, dispatchFakeEvent } from 'ng-zorro-antd/core/testing';
 
@@ -395,6 +396,36 @@ describe('input number', () => {
       fixture.detectChanges();
       expect(inputNumber.nativeElement.classList).not.toContain('ant-input-number-focused');
     });
+    describe('change detection behavior', () => {
+      it('should not run change detection on keyup and keydown events', done => {
+        const ngZone = TestBed.inject(NgZone);
+        const appRef = TestBed.inject(ApplicationRef);
+        spyOn(appRef, 'tick');
+        spyOn(inputNumber.componentInstance, 'stop').and.callThrough();
+
+        inputElement.dispatchEvent(new KeyboardEvent('keyup'));
+        expect(appRef.tick).toHaveBeenCalledTimes(0);
+        expect(inputNumber.componentInstance.stop).toHaveBeenCalled();
+
+        inputElement.dispatchEvent(
+          new KeyboardEvent('keydown', {
+            keyCode: TAB
+          })
+        );
+        expect(appRef.tick).toHaveBeenCalledTimes(0);
+
+        inputElement.dispatchEvent(
+          new KeyboardEvent('keydown', {
+            keyCode: ENTER
+          })
+        );
+
+        ngZone.onMicrotaskEmpty.pipe(take(1)).subscribe(() => {
+          expect(appRef.tick).toHaveBeenCalledTimes(1);
+          done();
+        });
+      });
+    });
   });
 
   describe('input number form', () => {