From aca0f418baf4890b8be3c1214be70819e4b88a95 Mon Sep 17 00:00:00 2001
From: Joshua Gross <joshuagross@fb.com>
Date: Mon, 22 Mar 2021 18:45:03 -0700
Subject: [PATCH] Change State references to TextLayoutManager to a weak_ptr
 (ParagraphState)

Summary:
TextLayoutManager indirectly holds ShadowNodes, which could hold onto TextLayoutManager via a shared_ptr; so we probably have some reference cycles here.

Changelog: [Internal]

Reviewed By: sammy-SC

Differential Revision: D27238439

fbshipit-source-id: b0b65cc451891e75bafddb7a08aa34ddf86d6a35
---
 .../Text/RCTParagraphComponentView.mm         | 28 ++++++++++---------
 .../components/text/ParagraphShadowNode.cpp   |  8 +-----
 .../renderer/components/text/ParagraphState.h |  6 ++--
 3 files changed, 20 insertions(+), 22 deletions(-)

diff --git a/React/Fabric/Mounting/ComponentViews/Text/RCTParagraphComponentView.mm b/React/Fabric/Mounting/ComponentViews/Text/RCTParagraphComponentView.mm
index 3425d844e51..bc0fa7b8417 100644
--- a/React/Fabric/Mounting/ComponentViews/Text/RCTParagraphComponentView.mm
+++ b/React/Fabric/Mounting/ComponentViews/Text/RCTParagraphComponentView.mm
@@ -106,8 +106,8 @@ using namespace facebook::react;
     return;
   }
 
-  auto textLayoutManager = _state->getData().layoutManager;
-  assert(textLayoutManager && "TextLayoutManager must not be `nullptr`.");
+  auto textLayoutManager = _state->getData().layoutManager.lock();
+  //  assert(textLayoutManager && "TextLayoutManager must not be `nullptr`.");
 
   if (!textLayoutManager) {
     return;
@@ -152,14 +152,18 @@ using namespace facebook::react;
   auto &data = _state->getData();
 
   if (![_accessibilityProvider isUpToDate:data.attributedString]) {
-    RCTTextLayoutManager *textLayoutManager =
-        (RCTTextLayoutManager *)unwrapManagedObject(data.layoutManager->getNativeTextLayoutManager());
-    CGRect frame = RCTCGRectFromRect(_layoutMetrics.getContentFrame());
-    _accessibilityProvider = [[RCTParagraphComponentAccessibilityProvider alloc] initWithString:data.attributedString
-                                                                                  layoutManager:textLayoutManager
-                                                                            paragraphAttributes:data.paragraphAttributes
-                                                                                          frame:frame
-                                                                                           view:self];
+    auto textLayoutManager = data.layoutManager.lock();
+    if (textLayoutManager) {
+      RCTTextLayoutManager *nativeTextLayoutManager =
+          (RCTTextLayoutManager *)unwrapManagedObject(textLayoutManager->getNativeTextLayoutManager());
+      CGRect frame = RCTCGRectFromRect(_layoutMetrics.getContentFrame());
+      _accessibilityProvider =
+          [[RCTParagraphComponentAccessibilityProvider alloc] initWithString:data.attributedString
+                                                               layoutManager:nativeTextLayoutManager
+                                                         paragraphAttributes:data.paragraphAttributes
+                                                                       frame:frame
+                                                                        view:self];
+    }
   }
 
   return _accessibilityProvider.accessibilityElements;
@@ -178,9 +182,7 @@ using namespace facebook::react;
     return _eventEmitter;
   }
 
-  auto textLayoutManager = _state->getData().layoutManager;
-
-  assert(textLayoutManager && "TextLayoutManager must not be `nullptr`.");
+  auto textLayoutManager = _state->getData().layoutManager.lock();
 
   if (!textLayoutManager) {
     return _eventEmitter;
diff --git a/ReactCommon/react/renderer/components/text/ParagraphShadowNode.cpp b/ReactCommon/react/renderer/components/text/ParagraphShadowNode.cpp
index 0c485964273..4d78d91b412 100644
--- a/ReactCommon/react/renderer/components/text/ParagraphShadowNode.cpp
+++ b/ReactCommon/react/renderer/components/text/ParagraphShadowNode.cpp
@@ -102,13 +102,7 @@ void ParagraphShadowNode::updateStateIfNeeded(Content const &content) {
 
   auto &state = getStateData();
 
-  react_native_assert(textLayoutManager_);
-  react_native_assert(
-      (!state.layoutManager || state.layoutManager == textLayoutManager_) &&
-      "`StateData` refers to a different `TextLayoutManager`");
-
-  if (state.attributedString == content.attributedString &&
-      state.layoutManager == textLayoutManager_) {
+  if (state.attributedString == content.attributedString) {
     return;
   }
 
diff --git a/ReactCommon/react/renderer/components/text/ParagraphState.h b/ReactCommon/react/renderer/components/text/ParagraphState.h
index bc72ac28c55..b31b8798d84 100644
--- a/ReactCommon/react/renderer/components/text/ParagraphState.h
+++ b/ReactCommon/react/renderer/components/text/ParagraphState.h
@@ -40,14 +40,16 @@ class ParagraphState final {
    * `TextLayoutManager` provides a connection to platform-specific
    * text rendering infrastructure which is capable to render the
    * `AttributedString`.
+   * This is not on every platform. This is not used on Android, but is
+   * used on the iOS mounting layer.
    */
-  SharedTextLayoutManager layoutManager;
+  std::weak_ptr<TextLayoutManager const> layoutManager;
 
 #ifdef ANDROID
   ParagraphState(
       AttributedString const &attributedString,
       ParagraphAttributes const &paragraphAttributes,
-      SharedTextLayoutManager const &layoutManager)
+      std::weak_ptr<const TextLayoutManager> const &layoutManager)
       : attributedString(attributedString),
         paragraphAttributes(paragraphAttributes),
         layoutManager(layoutManager) {}