From 01f16e4bb4d78c3e3737b7673b6e3825f4685593 Mon Sep 17 00:00:00 2001
From: luoyz <luoyz2349@outlook.com>
Date: Sun, 5 Nov 2023 17:16:21 +0800
Subject: [PATCH] fix(hot-reload): only reset hooks if error occurs

---
 CHANGELOG.md          |  4 ++++
 example/lib/main.dart | 28 ++++++++++++++++++++++------
 example/pubspec.lock  |  2 +-
 lib/src/fc.dart       | 16 +++++++++++++---
 pubspec.yaml          |  2 +-
 5 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1a81512..17f421c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.5.1
+
+* [Hot Reload] only reset hooks if error occurs after reassemble
+
 ## 0.5.0
 
 * [Hot Reload] reset hooks after reassemble
diff --git a/example/lib/main.dart b/example/lib/main.dart
index ad89c8d..f1cd204 100644
--- a/example/lib/main.dart
+++ b/example/lib/main.dart
@@ -4,7 +4,7 @@ import 'package:flutter_fc/flutter_fc.dart';
 void main() {
   runApp(const MaterialApp(
     home: SafeArea(
-      child: ReComputeAfterReassembleTestScreen(),
+      child: SkipErrorAfterReassembleTestScreen(),
     ),
   ));
 }
@@ -50,14 +50,30 @@ class ErrorTestScreen extends FCWidget {
 }
 
 /// value memoized with no deps, should be re-derived after reassemble
-class ReComputeAfterReassembleTestScreen extends FCWidget {
-  const ReComputeAfterReassembleTestScreen({super.key});
+class SkipErrorAfterReassembleTestScreen extends FCWidget {
+  const SkipErrorAfterReassembleTestScreen({super.key});
 
   @override
   Widget build(BuildContext context) {
-    var value;
-    value = useMemo(() => 1 /* try 2 after build */, const []);
-    return Text("$value");
+    final now = useMemo(() => DateTime.now(), const []);
+    return Scaffold(
+      body: Column(
+        children: [
+          Text("$now"),
+          DangerousFC(),
+        ],
+      ),
+    );
+  }
+}
+
+class DangerousFC extends FCWidget {
+  static var flag = 0;
+  @override
+  Widget build(BuildContext context) {
+    flag++;
+    final rs = flag % 2 == 0 ? useMemo(() => 1, const []) : useRef(2).current;
+    return Text("$rs%");
   }
 }
 
diff --git a/example/pubspec.lock b/example/pubspec.lock
index 7af9ca8..be89e23 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -68,7 +68,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.5.0"
+    version: "0.5.1"
   flutter_lints:
     dependency: "direct dev"
     description:
diff --git a/lib/src/fc.dart b/lib/src/fc.dart
index 22a0303..7ac0834 100644
--- a/lib/src/fc.dart
+++ b/lib/src/fc.dart
@@ -222,6 +222,8 @@ class _FCElement<T extends _FCWidget> extends ComponentElement
   @override
   List<Hook>? memoizedHooks;
 
+  var _reassembled = false;
+
   _FCElement(super.widget);
 
   @override
@@ -254,8 +256,8 @@ class _FCElement<T extends _FCWidget> extends ComponentElement
 
   @override
   void reassemble() {
+    _reassembled = true;
     super.reassemble();
-    memoizedHooks = null;
   }
 
   @override
@@ -287,6 +289,8 @@ class _FCElement<T extends _FCWidget> extends ComponentElement
   }
 
   Widget _buildWithHooks() {
+    final reassembledJust = _reassembled;
+    _reassembled = false;
     if (memoizedHooks == null) {
       _kCurrentDispatcher = _FCMountDispatcher(this);
     } else {
@@ -297,8 +301,14 @@ class _FCElement<T extends _FCWidget> extends ComponentElement
       memoizedHooks = _kCurrentDispatcher!.memoizedHooks;
       return built;
     } catch (e) {
-      memoizedHooks = null;
-      rethrow;
+      if (reassembledJust) {
+        memoizedHooks = null;
+        final built = widget.build(this);
+        memoizedHooks = _kCurrentDispatcher!.memoizedHooks;
+        return built;
+      } else {
+        rethrow;
+      }
     } finally {
       _kCurrentDispatcher = null;
     }
diff --git a/pubspec.yaml b/pubspec.yaml
index 917b600..6d3487d 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: flutter_fc
 description: Writing Function Component in Flutter, just as writing in React.
-version: 0.5.0
+version: 0.5.1
 homepage: https://github.com/luo3house/flutter_fc
 
 environment: