From 5439460d1fe166f8ec34ab7d48f05e0dd7f6a946 Mon Sep 17 00:00:00 2001
From: Naji <54370141+naaajii@users.noreply.github.com>
Date: Mon, 2 Sep 2024 15:22:16 +0500
Subject: [PATCH] fix(cdk/scrolling): adds ngTemplateContextGuard (#27276)

BREAKING CHANGE:
* Virtual scrolling lists now have proper type checking which can reveal some previously-hidden compilation errors.

* fix(cdk/scrolling): adds ngTemplateContextGuard

implements ngTemplateContextGuard for CdkVirtualForOf directive

fixes #26609

* fixup! fix(cdk/scrolling): adds ngTemplateContextGuard
---
 src/cdk/scrolling/virtual-for-of.ts     | 7 +++++++
 tools/public_api_guard/cdk/scrolling.md | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/src/cdk/scrolling/virtual-for-of.ts b/src/cdk/scrolling/virtual-for-of.ts
index 2b1d0b89c137..0407383f97a5 100644
--- a/src/cdk/scrolling/virtual-for-of.ts
+++ b/src/cdk/scrolling/virtual-for-of.ts
@@ -395,4 +395,11 @@ export class CdkVirtualForOf<T>
       index,
     };
   }
+
+  static ngTemplateContextGuard<T>(
+    directive: CdkVirtualForOf<T>,
+    context: unknown,
+  ): context is CdkVirtualForOfContext<T> {
+    return true;
+  }
 }
diff --git a/tools/public_api_guard/cdk/scrolling.md b/tools/public_api_guard/cdk/scrolling.md
index ca520ef4b7df..014312a5189b 100644
--- a/tools/public_api_guard/cdk/scrolling.md
+++ b/tools/public_api_guard/cdk/scrolling.md
@@ -120,6 +120,8 @@ export class CdkVirtualForOf<T> implements CdkVirtualScrollRepeater<T>, Collecti
     ngDoCheck(): void;
     // (undocumented)
     ngOnDestroy(): void;
+    // (undocumented)
+    static ngTemplateContextGuard<T>(directive: CdkVirtualForOf<T>, context: unknown): context is CdkVirtualForOfContext<T>;
     readonly viewChange: Subject<ListRange>;
     // (undocumented)
     static ɵdir: i0.ɵɵDirectiveDeclaration<CdkVirtualForOf<any>, "[cdkVirtualFor][cdkVirtualForOf]", never, { "cdkVirtualForOf": { "alias": "cdkVirtualForOf"; "required": false; }; "cdkVirtualForTrackBy": { "alias": "cdkVirtualForTrackBy"; "required": false; }; "cdkVirtualForTemplate": { "alias": "cdkVirtualForTemplate"; "required": false; }; "cdkVirtualForTemplateCacheSize": { "alias": "cdkVirtualForTemplateCacheSize"; "required": false; }; }, {}, never, never, true, never>;