fixup! fix(core): apply and remove stylesheets based on containing StyleRoot

JeanMeche · JeanMeche · commit 1eeaba920340 · 2025-12-14T13:58:56.000+01:00
diff --git a/packages/core/test/acceptance/hmr_spec.ts b/packages/core/test/acceptance/hmr_spec.ts
@@ -38,9 +38,11 @@ import {compileComponent} from '../../src/render3/jit/directive';
 import {angularCoreEnv} from '../../src/render3/jit/environment';
 import {clearTranslations, loadTranslations} from '@angular/localize';
 import {computeMsgId} from '@angular/compiler';
-import {EVENT_MANAGER_PLUGINS} from '@angular/platform-browser';
+import {
+  EVENT_MANAGER_PLUGINS,
+  ɵSharedStylesHost as SharedStylesHost,
+} from '@angular/platform-browser';
 import {ComponentType} from '../../src/render3';
-import {ɵSharedStylesHost as SharedStylesHost} from '@angular/platform-browser';
 import {isNode} from '@angular/private/testing';
 
 describe('hot module replacement', () => {
diff --git a/packages/core/test/render3/util/view_traversal_util_spec.ts b/packages/core/test/render3/util/view_traversal_util_spec.ts
@@ -1,3 +1,11 @@
+/*!
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
 import {NgComponentOutlet} from '@angular/common';
 import {By} from '@angular/platform-browser';
 import {Component} from '../../../src/core';
diff --git a/packages/platform-browser/src/dom/dom_renderer.ts b/packages/platform-browser/src/dom/dom_renderer.ts
@@ -599,8 +599,8 @@ class NoneEncapsulationDomRenderer extends DefaultDomRenderer2 {
   applyStyles(styleRoot: StyleRoot): void {
     // TODO: Apply styles on legacy shadow root creation afterwards?
 
-    const isShadowRoot = styleRoot instanceof ShadowRoot;
-    const isIsolatedShadowRoot = isShadowRoot && !allLegacyShadowRoots.has(styleRoot as ShadowRoot);
+    const isShadowRoot = isShadowRootInstance(styleRoot);
+    const isIsolatedShadowRoot = isShadowRoot && !allLegacyShadowRoots.has(styleRoot);
     if (isIsolatedShadowRoot) {
       // For isolated shadow roots, we limit to the one usage.
       this.sharedStylesHost.addStyles(styleRoot, this.styles, this.styleUrls);
@@ -623,9 +623,8 @@ class NoneEncapsulationDomRenderer extends DefaultDomRenderer2 {
 
     // TODO: Problematic?
     if (allLeavingAnimations.size === 0) {
-      const isShadowRoot = styleRoot instanceof ShadowRoot;
-      const isIsolatedShadowRoot =
-        isShadowRoot && !allLegacyShadowRoots.has(styleRoot as ShadowRoot);
+      const isShadowRoot = isShadowRootInstance(styleRoot);
+      const isIsolatedShadowRoot = isShadowRoot && !allLegacyShadowRoots.has(styleRoot);
       if (isIsolatedShadowRoot) {
         // For isolated shadow roots, we limit to the one usage.
         this.sharedStylesHost.removeStyles(styleRoot, this.styles, this.styleUrls);
@@ -688,3 +687,10 @@ class EmulatedEncapsulationDomRenderer2 extends NoneEncapsulationDomRenderer {
     return el;
   }
 }
+
+/**
+ * In some runtimes (e.g. server-side with Domino or node unit tests), ShadowRoot may not be defined.
+ */
+function isShadowRootInstance(obj: unknown): obj is ShadowRoot {
+  return typeof ShadowRoot !== 'undefined' && obj instanceof ShadowRoot;
+}
