From bd9f89d1c8e295f00ef3399c6bedca4e2ce0e89e Mon Sep 17 00:00:00 2001
From: Kristiyan Kostadinov <crisbeto@abv.bg>
Date: Wed, 27 Dec 2023 17:53:30 +0200
Subject: [PATCH] fix(common): server-side rendering error when using in-memory
 scrolling (#53683)

Fixes that the `BrowserViewportScroller` was throwing an error during server-side rendering because it was accessing `window` directly. Also removes some assertions that aren't necessary anymore.

Fixes #53682.

PR Close #53683
---
 packages/common/src/viewport_scroller.ts | 33 ++++++------------------
 1 file changed, 8 insertions(+), 25 deletions(-)

diff --git a/packages/common/src/viewport_scroller.ts b/packages/common/src/viewport_scroller.ts
index 761c22057b7..0e4a5488629 100644
--- a/packages/common/src/viewport_scroller.ts
+++ b/packages/common/src/viewport_scroller.ts
@@ -6,9 +6,10 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ɵɵdefineInjectable, ɵɵinject} from '@angular/core';
+import {inject, PLATFORM_ID, ɵɵdefineInjectable} from '@angular/core';
 
 import {DOCUMENT} from './dom_tokens';
+import {isPlatformBrowser} from './platform_id';
 
 
 
@@ -24,7 +25,9 @@ export abstract class ViewportScroller {
   static ɵprov = /** @pureOrBreakMyCode */ ɵɵdefineInjectable({
     token: ViewportScroller,
     providedIn: 'root',
-    factory: () => new BrowserViewportScroller(ɵɵinject(DOCUMENT), window)
+    factory: () => isPlatformBrowser(inject(PLATFORM_ID)) ?
+        new BrowserViewportScroller(inject(DOCUMENT), window) :
+        new NullViewportScroller()
   });
 
   /**
@@ -88,11 +91,7 @@ export class BrowserViewportScroller implements ViewportScroller {
    * @returns The position in screen coordinates.
    */
   getScrollPosition(): [number, number] {
-    if (this.supportsScrolling()) {
-      return [this.window.pageXOffset, this.window.pageYOffset];
-    } else {
-      return [0, 0];
-    }
+    return [this.window.scrollX, this.window.scrollY];
   }
 
   /**
@@ -100,9 +99,7 @@ export class BrowserViewportScroller implements ViewportScroller {
    * @param position The new position in screen coordinates.
    */
   scrollToPosition(position: [number, number]): void {
-    if (this.supportsScrolling()) {
-      this.window.scrollTo(position[0], position[1]);
-    }
+    this.window.scrollTo(position[0], position[1]);
   }
 
   /**
@@ -117,10 +114,6 @@ export class BrowserViewportScroller implements ViewportScroller {
    * @see https://html.spec.whatwg.org/#scroll-to-fragid
    */
   scrollToAnchor(target: string): void {
-    if (!this.supportsScrolling()) {
-      return;
-    }
-
     const elSelected = findAnchorFromDocument(this.document, target);
 
     if (elSelected) {
@@ -139,9 +132,7 @@ export class BrowserViewportScroller implements ViewportScroller {
    * Disables automatic scroll restoration provided by the browser.
    */
   setHistoryScrollRestoration(scrollRestoration: 'auto'|'manual'): void {
-    if (this.supportsScrolling()) {
-      this.window.history.scrollRestoration = scrollRestoration;
-    }
+    this.window.history.scrollRestoration = scrollRestoration;
   }
 
   /**
@@ -157,14 +148,6 @@ export class BrowserViewportScroller implements ViewportScroller {
     const offset = this.offset();
     this.window.scrollTo(left - offset[0], top - offset[1]);
   }
-
-  private supportsScrolling(): boolean {
-    try {
-      return !!this.window && !!this.window.scrollTo && 'pageXOffset' in this.window;
-    } catch {
-      return false;
-    }
-  }
 }
 
 function findAnchorFromDocument(document: Document, target: string): HTMLElement|null {