🪳 Fixed a bug where a Promise might never resolve when calling Resolve or Reject immediately within an asynchronous method of JavaScriptNativeObject.

Author: XuanchenLin

src/WinFormium/JavaScript/JavaScriptEngine.Render.cs

@@ -97,7 +97,7 @@ private void OnJsResolveOrRejectRemotePromise(ProcessMessage args)
                 using (CefObjectTracker.StartTracking())
                 using (context.EnterOrFail())
                 {
-                    var promise = promiseData.Promise;
+                    using var promise = promiseData.Promise;
 
                     if (message.Resolve)
                     {
@@ -117,7 +117,7 @@ private void OnJsResolveOrRejectRemotePromise(ProcessMessage args)
                         promise.RejectPromise(message.Data ?? string.Empty);
                     }
 
-                    promise.Dispose();
+                    //promise.Dispose();
                 }
             }));
         }

src/WinFormium/JavaScript/JavaScriptEngine.cs

@@ -253,7 +253,6 @@ private ProcessResponse OnJSCallNativeObjectMethod(ProcessRequest request)
             };
         }
 
-
         if (args.Asynconous)
         {
             var promise = args.Promise;
@@ -264,9 +263,6 @@ private ProcessResponse OnJSCallNativeObjectMethod(ProcessRequest request)
                 return new ProcessResponse { Success = false, ExceptionMessage = "[WinFormium] CallNativeObjectMethod returned promise but it is null." };
             }
 
-            args.ReturnValue = $"{promise.GenerateCallId()}";
-
-
             promise.CallRemoteResovle += (json) =>
             {
                 frame.SendProcessMessage(CefProcessId.Renderer, new JsResolveOrRejectRemotePromise
@@ -286,6 +282,11 @@ private ProcessResponse OnJSCallNativeObjectMethod(ProcessRequest request)
                     Data = reason
                 }.ToCefProcessMessage());
             };
+
+            args.ReturnValue = $"{promise.GenerateCallId()}";
+
+            promise.IsPromiseContextReady = true;
+
         }
 
 

src/WinFormium/JavaScript/JavaScriptNativeObject.cs

@@ -1,4 +1,4 @@
-// This file is part of the WinFormium project.
+// This file is part of the WinFormium project.
 // Copyright (c) 2025 Xuanchen Lin all rights reserved.
 // This project is licensed under the LGPL License.
 // See the LICENSE file in the project root for more information.
@@ -162,6 +162,7 @@ public override void OnFunctionApply(NativeProxyObjectFunctionApplyEventArgs arg
         else if (_asyncFunctions.TryGetValue(args.PropertyName, out var asyncFunc))
         {
             var promise = args.ReturnPromise();
+
             asyncFunc(args.ArgumentsAsJson, promise);
         }
     }

src/WinFormium/JavaScript/JavaScriptPromiseContext.cs

@@ -1,4 +1,4 @@
-// This file is part of the WinFormium project.
+// This file is part of the WinFormium project.
 // Copyright (c) 2025 Xuanchen Lin all rights reserved.
 // This project is licensed under the LGPL License.
 // See the LICENSE file in the project root for more information.
@@ -15,6 +15,37 @@ public class JavaScriptPromiseContext
     /// </summary>
     private string? _remoteCallId = null;
 
+    internal bool IsPromiseContextReady
+    {
+        get;
+        set
+        {
+            field = value;
+
+            if (_resolvesShouldBeCalledWhenContextReady is not null)
+            {
+                
+                _resolvesShouldBeCalledWhenContextReady.Invoke();
+            }
+            else if(_rejectsShouldBeCalledWhenContextReady is not null)
+            {
+                _rejectsShouldBeCalledWhenContextReady.Invoke();
+            }
+        }
+    }
+
+    /// <summary>
+    /// Gets or sets the action to invoke when the promise is resolved, if the context is not yet ready.
+    /// </summary>
+    private Action? _resolvesShouldBeCalledWhenContextReady;
+
+    /// <summary>
+    /// Gets or sets the action to invoke when the promise is rejected, if the context is not yet ready.
+    /// </summary>
+    private Action? _rejectsShouldBeCalledWhenContextReady;
+
+
+
     /// <summary>
     /// Generates and returns a unique call identifier for the remote promise invocation.
     /// </summary>
@@ -52,13 +83,25 @@ internal JavaScriptPromiseContext(int objectId)
         ObjectId = objectId;
     }
 
+    
+
     /// <summary>
     /// Resolves the promise with an optional return value in JSON format.
     /// </summary>
     /// <param name="returnValueAsJson">The return value as a JSON string, or <c>null</c> if not applicable.</param>
     public void Resolve(string? returnValueAsJson = null)
     {
-        CallRemoteResovle?.Invoke(returnValueAsJson);
+        if(IsPromiseContextReady)
+        {
+            CallRemoteResovle?.Invoke(returnValueAsJson);
+        }
+        else
+        {
+            _resolvesShouldBeCalledWhenContextReady = () =>
+            {
+                CallRemoteResovle?.Invoke(returnValueAsJson);
+            };
+        }
     }
 
     /// <summary>
@@ -67,7 +110,17 @@ public void Resolve(string? returnValueAsJson = null)
     /// <param name="reason">The reason for rejection, or <c>null</c> if not specified.</param>
     public void Reject(string? reason = null)
     {
-        CallRemoteReject?.Invoke(reason);
+        if(IsPromiseContextReady)
+        {
+            CallRemoteReject?.Invoke(reason);
+        }
+        else
+        {
+            _rejectsShouldBeCalledWhenContextReady = () =>
+            {
+                CallRemoteReject?.Invoke(reason);
+            };
+        }
     }
 
     /// <summary>

src/WinFormium/WinFormium.csproj

@@ -29,7 +29,7 @@
     </PropertyGroup>
 
     <PropertyGroup Condition="'$(Configuration)'=='Release'">
-        <Version>1.2.109.7</Version>
+        <Version>1.2.109.8</Version>
         <GeneratePackageOnBuild>True</GeneratePackageOnBuild>
         <GenerateDocumentationFile>True</GenerateDocumentationFile>
         <IncludeSymbols>true</IncludeSymbols>