From 36ce7ed9e987190f08547cfe0863dece19b3307f Mon Sep 17 00:00:00 2001
From: Rodrigo Rodrigues <rfr0067@hotmail.com>
Date: Fri, 1 Mar 2024 20:02:07 -0300
Subject: [PATCH] fix: [#1285] Prevent contains from accessing properties of
 undefined arguments

---
 packages/happy-dom/src/nodes/node/Node.ts       | 5 ++++-
 packages/happy-dom/test/nodes/node/Node.test.ts | 5 +++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/packages/happy-dom/src/nodes/node/Node.ts b/packages/happy-dom/src/nodes/node/Node.ts
index ff19017d3..ad00b175f 100644
--- a/packages/happy-dom/src/nodes/node/Node.ts
+++ b/packages/happy-dom/src/nodes/node/Node.ts
@@ -298,7 +298,10 @@ export default class Node extends EventTarget implements INode {
 	 * @param otherNode Node to test with.
 	 * @returns "true" if this node contains the other node.
 	 */
-	public contains(otherNode: INode): boolean {
+	public contains(otherNode: INode | undefined): boolean {
+		if (otherNode === undefined) {
+			return false;
+		}
 		return NodeUtility.isInclusiveAncestor(this, otherNode);
 	}
 
diff --git a/packages/happy-dom/test/nodes/node/Node.test.ts b/packages/happy-dom/test/nodes/node/Node.test.ts
index f840ad095..58f1586b3 100644
--- a/packages/happy-dom/test/nodes/node/Node.test.ts
+++ b/packages/happy-dom/test/nodes/node/Node.test.ts
@@ -330,6 +330,11 @@ describe('Node', () => {
 
 			expect(div.contains(null)).toBe(false);
 		});
+		it('Returns "false" if match node is undefined.', () => {
+			const div = document.createElement('div');
+
+			expect(div.contains(undefined)).toBe(false);
+		});
 	});
 
 	describe('getRootNode()', () => {