From 31453c08b3053ad5a644c5fbd0883521bde85bc9 Mon Sep 17 00:00:00 2001
From: Andrew Scott <atscott@google.com>
Date: Fri, 27 Oct 2023 14:09:01 -0700
Subject: [PATCH] docs(core): Deprecate `ChangeDetectorRef.checkNoChanges`
 (#52431)

The `checkNoChanges` method does not belong in the API of production interface. `checkNoChanges` is
limited to testing and should not be used in any application code. Test
code should use `ComponentFixture` instead of `ChangeDetectorRef`.
Additionally, it is not desirable to have the `checkNoChanges` API
available in a context where `detectChanges` is not run first.

DEPRECATED: `ChangeDetectorRef.checkNoChanges` is deprecated.

Test code should use `ComponentFixture` instead of `ChangeDetectorRef`.
Application code should not call `ChangeDetectorRef.checkNoChanges` directly.

PR Close #52431
---
 goldens/public-api/core/index.md                          | 1 +
 packages/core/src/change_detection/change_detector_ref.ts | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/goldens/public-api/core/index.md b/goldens/public-api/core/index.md
index 1144346016742..e0c06b1c2ee6d 100644
--- a/goldens/public-api/core/index.md
+++ b/goldens/public-api/core/index.md
@@ -168,6 +168,7 @@ export enum ChangeDetectionStrategy {
 
 // @public
 export abstract class ChangeDetectorRef {
+    // @deprecated
     abstract checkNoChanges(): void;
     abstract detach(): void;
     abstract detectChanges(): void;
diff --git a/packages/core/src/change_detection/change_detector_ref.ts b/packages/core/src/change_detection/change_detector_ref.ts
index 6bd0102fdc4a8..4dc711d5ba58f 100644
--- a/packages/core/src/change_detection/change_detector_ref.ts
+++ b/packages/core/src/change_detection/change_detector_ref.ts
@@ -104,6 +104,10 @@ export abstract class ChangeDetectorRef {
    *
    * Use in development mode to verify that running change detection doesn't introduce
    * other changes. Calling it in production mode is a noop.
+   *
+   * @deprecated This is a test-only API that does not have a place in production interface.
+   * `checkNoChanges` is already part of an `ApplicationRef` tick when the app is running in dev
+   * mode. For more granular `checkNoChanges` validation, use `ComponentFixture`.
    */
   abstract checkNoChanges(): void;