完成 P2 前架构整改

My project/Assets/FlowScope/Tests/PlayMode/UI/UIPreloadServiceTests.cs

@@ -1,6 +1,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Threading;
+using System.Threading.Tasks;
 using FlowScope.UI;
 using NUnit.Framework;
 using UnityEngine;
@@ -58,6 +59,27 @@ namespace FlowScope.Tests.PlayMode.UI
             Assert.That(resources.Handles, Has.Count.EqualTo(1));
         }
 
+        [UnityTest]
+        public IEnumerator PreloadAsync_WhenSamePanelLoadsConcurrently_UsesOneResourceLoad()
+        {
+            var prefab = CreatePrefab<ExplicitPathPanel>("ExplicitPathPrefab");
+            var resources = new GatedUITestResources("Custom/Explicit", prefab);
+            var preload = new UIPreloadService(resources);
+
+            var first = preload.PreloadAsync<ExplicitPathPanel>(CancellationToken.None);
+            var second = preload.PreloadAsync<ExplicitPathPanel>(CancellationToken.None);
+
+            Assert.That(resources.LoadCalls, Is.EqualTo(1));
+
+            resources.Complete();
+            yield return UITestAsync.Await(first);
+            yield return UITestAsync.Await(second);
+
+            Assert.That(resources.LoadCalls, Is.EqualTo(1));
+            Assert.That(resources.Handle.IsDisposed, Is.False);
+            Assert.That(preload.IsPreloaded<ExplicitPathPanel>(), Is.True);
+        }
+
         [UnityTest]
         public IEnumerator OpenAsync_WhenPanelIsPreloaded_ReusesPreloadedHandle()
         {
@@ -111,5 +133,52 @@ namespace FlowScope.Tests.PlayMode.UI
             gameObject.AddComponent<TPanel>();
             return gameObject;
         }
+
+        private sealed class GatedUITestResources : FlowScope.Resources.IResourceService
+        {
+            private readonly string _key;
+            private readonly GameObject _asset;
+            private readonly TaskCompletionSource<FlowScope.Resources.IResourceHandle<GameObject>> _gate =
+                new(TaskCreationOptions.RunContinuationsAsynchronously);
+
+            public GatedUITestResources(string key, GameObject asset)
+            {
+                _key = key;
+                _asset = asset;
+                Handle = new UITestResourceHandle<GameObject>(key, asset);
+            }
+
+            public int LoadCalls { get; private set; }
+            public UITestResourceHandle<GameObject> Handle { get; }
+
+            public Task<FlowScope.Resources.IResourceHandle<T>> LoadAsync<T>(
+                string key,
+                CancellationToken cancellationToken)
+                where T : class
+            {
+                cancellationToken.ThrowIfCancellationRequested();
+                LoadCalls++;
+                Assert.That(key, Is.EqualTo(_key));
+                return AwaitHandle<T>();
+            }
+
+            public FlowScope.Resources.IResourceGroup CreateGroup()
+            {
+                throw new System.NotSupportedException();
+            }
+
+            public void Complete()
+            {
+                _gate.SetResult(Handle);
+            }
+
+            private async Task<FlowScope.Resources.IResourceHandle<T>> AwaitHandle<T>()
+                where T : class
+            {
+                var handle = await _gate.Task;
+                Assert.That(handle.Asset, Is.SameAs(_asset));
+                return (FlowScope.Resources.IResourceHandle<T>)(object)handle;
+            }
+        }
     }
 }