Fixing double root folder creation.

Wino.Core.Tests/Synchronizers/WinoSynchronizerMailRequestTests.cs

@@ -0,0 +1,107 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using CommunityToolkit.Mvvm.Messaging;
+using FluentAssertions;
+using Wino.Core.Domain.Entities.Mail;
+using Wino.Core.Domain.Entities.Shared;
+using Wino.Core.Domain.Enums;
+using Wino.Core.Domain.Interfaces;
+using Wino.Core.Domain.Models.MailItem;
+using Wino.Core.Domain.Models.Synchronization;
+using Wino.Core.Requests.Folder;
+using Wino.Core.Synchronizers;
+using Xunit;
+
+namespace Wino.Core.Tests.Synchronizers;
+
+public sealed class WinoSynchronizerMailRequestTests
+{
+    [Fact]
+    public async Task FoldersOnly_sync_should_not_execute_queued_folder_requests()
+    {
+        var synchronizer = new TestMailSynchronizer();
+        var request = new CreateRootFolderRequest(
+            new MailItemFolder { Id = Guid.NewGuid(), MailAccountId = synchronizer.Account.Id },
+            "test");
+
+        synchronizer.QueueRequest(request);
+
+        var foldersOnlyResult = await synchronizer.SynchronizeMailsAsync(new MailSynchronizationOptions
+        {
+            AccountId = synchronizer.Account.Id,
+            Type = MailSynchronizationType.FoldersOnly
+        });
+
+        foldersOnlyResult.CompletedState.Should().Be(SynchronizationCompletedState.Success);
+        synchronizer.CreateRootFolderInvocationCount.Should().Be(0);
+        synchronizer.ExecuteNativeRequestsInvocationCount.Should().Be(0);
+
+        var executeRequestsResult = await synchronizer.SynchronizeMailsAsync(new MailSynchronizationOptions
+        {
+            AccountId = synchronizer.Account.Id,
+            Type = MailSynchronizationType.ExecuteRequests
+        });
+
+        executeRequestsResult.CompletedState.Should().Be(SynchronizationCompletedState.Success);
+        synchronizer.CreateRootFolderInvocationCount.Should().Be(1);
+        synchronizer.ExecuteNativeRequestsInvocationCount.Should().Be(1);
+    }
+
+    private sealed class TestMailSynchronizer
+        : WinoSynchronizer<object, object, object>
+    {
+        public TestMailSynchronizer()
+            : base(new MailAccount { Id = Guid.NewGuid(), Name = "Test account" }, WeakReferenceMessenger.Default)
+        {
+        }
+
+        public override uint BatchModificationSize => 1;
+        public override uint InitialMessageDownloadCountPerFolder => 0;
+        public int CreateRootFolderInvocationCount { get; private set; }
+        public int ExecuteNativeRequestsInvocationCount { get; private set; }
+
+        public override List<IRequestBundle<object>> CreateRootFolder(CreateRootFolderRequest request)
+        {
+            CreateRootFolderInvocationCount++;
+            return [new TestRequestBundle(new object(), request)];
+        }
+
+        public override Task ExecuteNativeRequestsAsync(List<IRequestBundle<object>> batchedRequests, CancellationToken cancellationToken = default)
+        {
+            ExecuteNativeRequestsInvocationCount++;
+            return Task.CompletedTask;
+        }
+
+        public override Task<List<NewMailItemPackage>> CreateNewMailPackagesAsync(
+            object message,
+            MailItemFolder assignedFolder,
+            CancellationToken cancellationToken = default)
+            => Task.FromResult(new List<NewMailItemPackage>());
+
+        protected override Task<MailSynchronizationResult> SynchronizeMailsInternalAsync(
+            MailSynchronizationOptions options,
+            CancellationToken cancellationToken = default)
+            => Task.FromResult(MailSynchronizationResult.Empty);
+
+        protected override Task<CalendarSynchronizationResult> SynchronizeCalendarEventsInternalAsync(
+            CalendarSynchronizationOptions options,
+            CancellationToken cancellationToken = default)
+            => Task.FromResult(CalendarSynchronizationResult.Empty);
+    }
+
+    private sealed class TestRequestBundle : IRequestBundle<object>
+    {
+        public TestRequestBundle(object nativeRequest, IRequestBase request)
+        {
+            NativeRequest = nativeRequest;
+            Request = request;
+        }
+
+        public string BundleId { get; set; } = Guid.NewGuid().ToString();
+        public IUIChangeRequest UIChangeRequest => Request;
+        public object NativeRequest { get; }
+        public IRequestBase Request { get; }
+    }
+}

Wino.Core/Synchronizers/WinoSynchronizer.cs

@@ -140,9 +140,10 @@ public abstract class WinoSynchronizer<TBaseRequest, TMessageType, TCalendarEven
             PendingSynchronizationRequest.Add(options, newCancellationTokenSource);
             activeSynchronizationCancellationToken = newCancellationTokenSource.Token;
 
-            // ImapSynchronizer will send this type when an Idle client receives a notification of changes.
+            // Only explicit ExecuteRequests runs are allowed to drain the queued request list.
-            // We should not execute requests in this case.
+            // Other sync types (for example the follow-up FoldersOnly refresh after folder actions)
-            bool shouldExecuteRequests = options.Type != MailSynchronizationType.IMAPIdle;
+            // may be queued alongside ExecuteRequests and must not replay the same operations.
+            bool shouldExecuteRequests = options.Type == MailSynchronizationType.ExecuteRequests;
 
             bool shouldDelayExecution = false;
             int maxExecutionDelay = 0;