From 7b1d42dfa2bcceeb3547d9ea59a3262686d0104f Mon Sep 17 00:00:00 2001
From: Rolf Bjarne Kvinge <rolf@xamarin.com>
Date: Wed, 4 Mar 2026 13:42:21 +0100
Subject: [PATCH] [sharpie] Add support for visionos_app_extension availability
 platform. Fixes #18098.

Sharpie's clang reports visionOS app extension availability as
'xros_app_extension', which was not handled in the GetPlatform()
switch statement, causing an 'Unsupported clang availability platform'
exception. This is the same class of bug as #18098.

Add:
- VisionOSAppExtension to the PlatformName enum
- Handle 'xros_app_extension' and 'visionos_app_extension' strings
  in GetPlatform()
- Test with all app extension availability platforms

Fixes https://github.com/dotnet/macios/issues/18098.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../sharpie/Tests/AvailabilityAppExtension.h  | 28 +++++++++++++++++
 .../AvailabilityAppExtension.iphoneos.cs      | 31 +++++++++++++++++++
 .../Attributes/AvailabilityBaseAttribute.cs   |  4 +++
 3 files changed, 63 insertions(+)
 create mode 100644 tests/sharpie/Tests/AvailabilityAppExtension.h
 create mode 100644 tests/sharpie/Tests/AvailabilityAppExtension.iphoneos.cs

diff --git a/tests/sharpie/Tests/AvailabilityAppExtension.h b/tests/sharpie/Tests/AvailabilityAppExtension.h
new file mode 100644
index 000000000000..f58804270cd1
--- /dev/null
+++ b/tests/sharpie/Tests/AvailabilityAppExtension.h
@@ -0,0 +1,28 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+// RUN iphoneos: -x objective-c -sdk iphoneos
+
+__attribute__((availability(ios_app_extension,unavailable)))
+@interface UnavailableiOSAppExtension
+@end
+
+__attribute__((availability(macosx_app_extension,unavailable)))
+@interface UnavailableMacOSXAppExtension
+@end
+
+__attribute__((availability(tvos_app_extension,unavailable)))
+@interface UnavailableTvOSAppExtension
+@end
+
+__attribute__((availability(watchos_app_extension,unavailable)))
+@interface UnavailableWatchOSAppExtension
+@end
+
+__attribute__((availability(maccatalyst_app_extension,unavailable)))
+@interface UnavailableMacCatalystAppExtension
+@end
+
+__attribute__((availability(visionos_app_extension,unavailable)))
+@interface UnavailableVisionOSAppExtension
+@end
diff --git a/tests/sharpie/Tests/AvailabilityAppExtension.iphoneos.cs b/tests/sharpie/Tests/AvailabilityAppExtension.iphoneos.cs
new file mode 100644
index 000000000000..02936969f053
--- /dev/null
+++ b/tests/sharpie/Tests/AvailabilityAppExtension.iphoneos.cs
@@ -0,0 +1,31 @@
+using ObjCRuntime;
+
+// @interface UnavailableiOSAppExtension
+[Unavailable (PlatformName.iOSAppExtension)]
+interface UnavailableiOSAppExtension {
+}
+
+// @interface UnavailableMacOSXAppExtension
+[Unavailable (PlatformName.MacOSXAppExtension)]
+interface UnavailableMacOSXAppExtension {
+}
+
+// @interface UnavailableTvOSAppExtension
+[Unavailable (PlatformName.TvOSAppExtension)]
+interface UnavailableTvOSAppExtension {
+}
+
+// @interface UnavailableWatchOSAppExtension
+[Unavailable (PlatformName.WatchOSAppExtension)]
+interface UnavailableWatchOSAppExtension {
+}
+
+// @interface UnavailableMacCatalystAppExtension
+[Unavailable (PlatformName.MacCatalystAppExtension)]
+interface UnavailableMacCatalystAppExtension {
+}
+
+// @interface UnavailableVisionOSAppExtension
+[Unavailable (PlatformName.VisionOSAppExtension)]
+interface UnavailableVisionOSAppExtension {
+}
diff --git a/tools/sharpie/Sharpie.Bind/Attributes/AvailabilityBaseAttribute.cs b/tools/sharpie/Sharpie.Bind/Attributes/AvailabilityBaseAttribute.cs
index f4885a96520f..43d88837e970 100644
--- a/tools/sharpie/Sharpie.Bind/Attributes/AvailabilityBaseAttribute.cs
+++ b/tools/sharpie/Sharpie.Bind/Attributes/AvailabilityBaseAttribute.cs
@@ -20,6 +20,7 @@ enum PlatformName : byte {
 	MacCatalyst,
 	DriverKit,
 	VisionOS,
+	VisionOSAppExtension,
 	MacCatalystAppExtension,
 }
 
@@ -155,6 +156,9 @@ static PlatformName GetPlatform (string? name)
 		case "visionOS":
 		case "visionos":
 			return PlatformName.VisionOS;
+		case "xros_app_extension":
+		case "visionos_app_extension":
+			return PlatformName.VisionOSAppExtension;
 		case "maccatalyst_app_extension":
 			return PlatformName.MacCatalystAppExtension;
 		default: