Exclude access key markers from native menu titles on macOS. (#13338)

* Add integration test for access key indicators in macOS menu bar titles.

Tests for access key indicators displaying as plain underscores in macOS menu bar items.

* Exclude access key markers from native menu titles on macOS.

macOS does not support access key markers, so they just display as extra underscores.

samples/IntegrationTestApp/MainWindow.axaml

@@ -18,6 +18,9 @@
       <NativeMenuItem Header="View">
         <NativeMenu/>
       </NativeMenuItem>
+      <NativeMenuItem Header="_Options">
+        <NativeMenu/>
+      </NativeMenuItem>
     </NativeMenu>
   </NativeMenu.Menu>
   <DockPanel>

src/Avalonia.Native/IAvnMenu.cs

@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Specialized;
+using Avalonia.Compatibility;
 using Avalonia.Reactive;
 using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
 
 namespace Avalonia.Native.Interop
 {
@@ -47,6 +49,20 @@ namespace Avalonia.Native.Interop.Impl
         private List<__MicroComIAvnMenuItemProxy> _menuItems = new List<__MicroComIAvnMenuItemProxy>();
         private Dictionary<NativeMenuItemBase, __MicroComIAvnMenuItemProxy> _menuItemLookup = new Dictionary<NativeMenuItemBase, __MicroComIAvnMenuItemProxy>();
 
+        private void UpdateTitle(string title)
+        {
+            if (OperatingSystemEx.IsMacOS())
+            {
+                // macOS does not process access key markers, so remove them.
+                title = AccessText.RemoveAccessKeyMarker(title);
+            }
+            if (string.IsNullOrWhiteSpace(title))
+            {
+                title = "";
+            }
+            SetTitle(title);
+        }
+
         public void RaiseNeedsUpdate()
         {
             (ManagedMenu as INativeMenuExporterEventsImplBridge).RaiseNeedsUpdate();
@@ -127,8 +143,7 @@ namespace Avalonia.Native.Interop.Impl
 
             ((INotifyCollectionChanged)ManagedMenu.Items).CollectionChanged += OnMenuItemsChanged;
 
-            if (!string.IsNullOrWhiteSpace(title)) 
-                SetTitle(title);
+            UpdateTitle(title);
         }
 
         public void Deinitialise()

src/Avalonia.Native/IAvnMenuItem.cs

@@ -1,7 +1,9 @@
 using System;
 using System.IO;
+using Avalonia.Compatibility;
 using Avalonia.Reactive;
 using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
 using Avalonia.Media.Imaging;
 using Avalonia.Platform.Interop;
 
@@ -22,7 +24,19 @@ namespace Avalonia.Native.Interop.Impl
 
         public NativeMenuItemBase ManagedMenuItem { get; set; }
 
-        private void UpdateTitle(string title) => SetTitle(title ?? "");
+        private void UpdateTitle(string title)
+        {
+            if (OperatingSystemEx.IsMacOS())
+            {
+                // macOS does not process access key markers, so remove them.
+                title = AccessText.RemoveAccessKeyMarker(title);
+            }
+            if (string.IsNullOrWhiteSpace(title))
+            {
+                title = "";
+            }
+            SetTitle(title);
+        }
 
         private void UpdateIsChecked(bool isChecked) => SetIsChecked(isChecked.AsComBool());
 

tests/Avalonia.IntegrationTests.Appium/NativeMenuTests.cs

@@ -49,5 +49,14 @@ namespace Avalonia.IntegrationTests.Appium
 
             Assert.True(buttonTab.Selected);
         }
+
+        [PlatformFact(TestPlatforms.MacOS)]
+        public void MacOS_Sanitizes_Access_Key_Markers_When_Included_In_Menu_Title()
+        {
+            var menuBar = _session.FindElementByXPath("/XCUIElementTypeApplication/XCUIElementTypeMenuBar");
+
+            Assert.True(menuBar.FindElementsByName("_Options").Count == 0);
+            Assert.True(menuBar.FindElementsByName("Options").Count == 1);
+        }
     }
 }