From 822bf52c29729d25b2bfb31655cf773609a9283d Mon Sep 17 00:00:00 2001
From: Ramanpreet Nara <ramanpreet@meta.com>
Date: Wed, 10 Jan 2024 12:35:33 -0800
Subject: [PATCH] BridgelessUIManager: Implement viewIsDescendantOf (#42209)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/42209

Implement UIManager.viewIsDescendentOf

Changelog: [Internal]

Reviewed By: sammy-SC

Differential Revision: D52449786

fbshipit-source-id: b607b29da935f468b00303ba20e3fe92db5291bd
---
 .../ReactNative/BridgelessUIManager.js        | 48 ++++++++++++++++++-
 1 file changed, 47 insertions(+), 1 deletion(-)

diff --git a/packages/react-native/Libraries/ReactNative/BridgelessUIManager.js b/packages/react-native/Libraries/ReactNative/BridgelessUIManager.js
index 92bebb46db48f5..73ef30c8e45645 100644
--- a/packages/react-native/Libraries/ReactNative/BridgelessUIManager.js
+++ b/packages/react-native/Libraries/ReactNative/BridgelessUIManager.js
@@ -338,7 +338,53 @@ const UIManagerJS: UIManagerJSInterface & {[string]: any} = {
     ancestorReactTag: ?number,
     callback: (result: Array<boolean>) => void,
   ): void => {
-    raiseSoftError('viewIsDescendantOf');
+    if (reactTag == null) {
+      console.error(
+        `viewIsDescendantOf() noop: Cannot be called with ${String(
+          reactTag,
+        )} reactTag`,
+      );
+      return;
+    }
+
+    const FabricUIManager = nullthrows(getFabricUIManager());
+    const shadowNode = FabricUIManager.findShadowNodeByTag_DEPRECATED(reactTag);
+    if (!shadowNode) {
+      console.error(
+        `viewIsDescendantOf() noop: Cannot find view with reactTag ${reactTag}`,
+      );
+      return;
+    }
+
+    if (ancestorReactTag == null) {
+      console.error(
+        `viewIsDescendantOf() noop: Cannot be called with ${String(
+          ancestorReactTag,
+        )} ancestorReactTag`,
+      );
+      return;
+    }
+
+    const ancestorShadowNode =
+      FabricUIManager.findShadowNodeByTag_DEPRECATED(ancestorReactTag);
+    if (!ancestorShadowNode) {
+      console.error(
+        `viewIsDescendantOf() noop: Cannot find view with ancestorReactTag ${ancestorReactTag}`,
+      );
+      return;
+    }
+
+    // Keep this in sync with ReadOnlyNode.js
+    const DOCUMENT_POSITION_CONTAINED_BY = 16;
+
+    let result = FabricUIManager.compareDocumentPosition(
+      ancestorShadowNode,
+      shadowNode,
+    );
+
+    let isAncestor = (result & DOCUMENT_POSITION_CONTAINED_BY) !== 0;
+
+    callback([isAncestor]);
   },
   configureNextLayoutAnimation: (
     config: Object,