Merge pull request #41678 from etcwilde/ewilde/protect-unavailable-from-async

Check unavailable from async in interface file

Author: etcwilde

include/swift/Basic/Features.def

@@ -75,5 +75,7 @@ SUPPRESSIBLE_LANGUAGE_FEATURE(SpecializeAttributeWithAvailability, 0, "@_special
 LANGUAGE_FEATURE(BuiltinAssumeAlignment, 0, "Builtin.assumeAlignment", true)
 SUPPRESSIBLE_LANGUAGE_FEATURE(UnsafeInheritExecutor, 0, "@_unsafeInheritExecutor", true)
 SUPPRESSIBLE_LANGUAGE_FEATURE(PrimaryAssociatedTypes, 0, "Primary associated types", true)
+SUPPRESSIBLE_LANGUAGE_FEATURE(UnavailableFromAsync, 0, "@_unavailableFromAsync", true)
+
 #undef SUPPRESSIBLE_LANGUAGE_FEATURE
 #undef LANGUAGE_FEATURE

lib/AST/ASTPrinter.cpp

@@ -3002,6 +3002,19 @@ static void suppressingFeaturePrimaryAssociatedTypes(PrintOptions &options,
   options.PrintPrimaryAssociatedTypes = originalPrintPrimaryAssociatedTypes;
 }
 
+static bool usesFeatureUnavailableFromAsync(Decl *decl) {
+  return decl->getAttrs().hasAttribute<UnavailableFromAsyncAttr>();
+}
+
+static void
+suppressingFeatureUnavailableFromAsync(PrintOptions &options,
+                                       llvm::function_ref<void()> action) {
+  unsigned originalExcludeAttrCount = options.ExcludeAttrList.size();
+  options.ExcludeAttrList.push_back(DAK_UnavailableFromAsync);
+  action();
+  options.ExcludeAttrList.resize(originalExcludeAttrCount);
+}
+
 /// Suppress the printing of a particular feature.
 static void suppressingFeature(PrintOptions &options, Feature feature,
                                llvm::function_ref<void()> action) {

test/ModuleInterface/features.swift

@@ -177,4 +177,12 @@ public func unsafeInheritExecutor() async {}
 @_specialize(exported: true, availability: SwiftStdlib 5.1, *; where T == Int)
 public func multipleSuppressible<T>(value: T) async {}
 
+// CHECK:      #if compiler(>=5.3) && $UnavailableFromAsync
+// CHECK-NEXT: @_unavailableFromAsync(message: "Test") public func unavailableFromAsyncFunc()
+// CHECK-NEXT: #else
+// CHECK-NEXT: public func unavailableFromAsyncFunc()
+// CHECK-NEXT: #endif
+@_unavailableFromAsync(message: "Test")
+public func unavailableFromAsyncFunc() { }
+
 // CHECK-NOT: extension FeatureTest.MyActor : Swift.Sendable