From 5da283e3a9824df1de1306347893062891da473b Mon Sep 17 00:00:00 2001
From: wood1986 <5212215+wood1986@users.noreply.github.com>
Date: Tue, 3 Jan 2023 11:41:40 -0800
Subject: [PATCH] fix: fix the potential race condition when dismissing and
 presentating modal (#35705)

Summary:
`react-native-screens` has a bug about `UIViewControllerHierarchyInconsistency` when dismissing a `react-native` `<Modal>`. Here is the bug https://github.com/software-mansion/react-native-screens/issues/944

After adding `dispatch_async` block, it solves the issue. But I do not know if this is right.

Here is the example repo https://github.com/wood1986/react-native-modal-crash

You can revert my last commit https://github.com/wood1986/react-native-modal-crash/commit/86e7bc1adf444c1645c0d6078b0d6d427cdf6a36 to reproduce the issue

## Changelog

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[IOS] [FIXED] - fixed the potential race condition when dismissing and presentating modal

Pull Request resolved: https://github.com/facebook/react-native/pull/35705

Reviewed By: cipolleschi

Differential Revision: D42253488

Pulled By: makovkastar

fbshipit-source-id: 3e98fa9e719ecdeddeb2a367b0cd364e15136d56
---
 React/Views/RCTModalHostViewManager.m | 28 +++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/React/Views/RCTModalHostViewManager.m b/React/Views/RCTModalHostViewManager.m
index 7fab70ef636368..4b9f9ad7267c8f 100644
--- a/React/Views/RCTModalHostViewManager.m
+++ b/React/Views/RCTModalHostViewManager.m
@@ -75,13 +75,15 @@ - (void)presentModalHostView:(RCTModalHostView *)modalHostView
       modalHostView.onShow(nil);
     }
   };
-  if (_presentationBlock) {
-    _presentationBlock([modalHostView reactViewController], viewController, animated, completionBlock);
-  } else {
-    [[modalHostView reactViewController] presentViewController:viewController
-                                                      animated:animated
-                                                    completion:completionBlock];
-  }
+  dispatch_async(dispatch_get_main_queue(), ^{
+    if (self->_presentationBlock) {
+      self->_presentationBlock([modalHostView reactViewController], viewController, animated, completionBlock);
+    } else {
+      [[modalHostView reactViewController] presentViewController:viewController
+                                                        animated:animated
+                                                      completion:completionBlock];
+    }
+  });
 }
 
 - (void)dismissModalHostView:(RCTModalHostView *)modalHostView
@@ -93,11 +95,13 @@ - (void)dismissModalHostView:(RCTModalHostView *)modalHostView
       [[self.bridge moduleForClass:[RCTModalManager class]] modalDismissed:modalHostView.identifier];
     }
   };
-  if (_dismissalBlock) {
-    _dismissalBlock([modalHostView reactViewController], viewController, animated, completionBlock);
-  } else {
-    [viewController.presentingViewController dismissViewControllerAnimated:animated completion:completionBlock];
-  }
+  dispatch_async(dispatch_get_main_queue(), ^{
+    if (self->_dismissalBlock) {
+      self->_dismissalBlock([modalHostView reactViewController], viewController, animated, completionBlock);
+    } else {
+      [viewController.presentingViewController dismissViewControllerAnimated:animated completion:completionBlock];
+    }
+  });
 }
 
 - (RCTShadowView *)shadowView