From 6521d5bc141fbdd86a7f02159a7c55f943949acc Mon Sep 17 00:00:00 2001
From: Kristiyan Kostadinov <crisbeto@abv.bg>
Date: Wed, 6 Mar 2024 14:18:34 +0100
Subject: [PATCH] fix(material/core): mark fields on HasErrorState as nullable

Updates a couple of the fields on `HasErrorState` to be nullable to align them with the `_ErrorStateTracker`.

Fixes #28688.
---
 src/material/core/common-behaviors/error-state.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/material/core/common-behaviors/error-state.ts b/src/material/core/common-behaviors/error-state.ts
index 88aeb448b4f3..e20993553291 100644
--- a/src/material/core/common-behaviors/error-state.ts
+++ b/src/material/core/common-behaviors/error-state.ts
@@ -33,14 +33,14 @@ type CanUpdateErrorStateCtor = Constructor<CanUpdateErrorState> &
 
 /** @docs-private */
 interface HasErrorState {
-  _parentFormGroup: FormGroupDirective;
-  _parentForm: NgForm;
+  _parentFormGroup: FormGroupDirective | null;
+  _parentForm: NgForm | null;
   _defaultErrorStateMatcher: ErrorStateMatcher;
 
   // These properties are defined as per the `MatFormFieldControl` interface. Since
   // this mixin is commonly used with custom form-field controls, we respect the
   // properties (also with the public name they need according to `MatFormFieldControl`).
-  ngControl: NgControl;
+  ngControl: NgControl | null;
   stateChanges: Subject<void>;
 }