Merge pull request swiftlang#22190 from harlanhaskins/show-me-the-protocol

[ParseableInterfaces] Print @_show_in_interface

Author: Harlan Haskins

include/swift/AST/PrintOptions.h

@@ -258,6 +258,7 @@ struct PrintOptions {
   /// List of attribute kinds that should not be printed.
   std::vector<AnyAttrKind> ExcludeAttrList = {DAK_Transparent, DAK_Effects,
                                               DAK_FixedLayout,
+                                              DAK_ShowInInterface,
                                               DAK_ImplicitlyUnwrappedOptional};
 
   /// List of attribute kinds that should be printed exclusively.

lib/AST/Attr.cpp

@@ -374,7 +374,6 @@ bool DeclAttribute::printImpl(ASTPrinter &Printer, const PrintOptions &Options,
   case DAK_RawDocComment:
   case DAK_ObjCBridged:
   case DAK_SynthesizedProtocol:
-  case DAK_ShowInInterface:
   case DAK_Rethrows:
   case DAK_Infix:
     return false;

test/ParseableInterface/show-in-interface.swift

@@ -0,0 +1,6 @@
+// RUN: %target-swift-frontend -typecheck %s -parse-stdlib -emit-parseable-module-interface-path - | %FileCheck %s
+
+// CHECK: @_show_in_interface public protocol _UnderscoredProtocol {
+// CHECK-NEXT: }
+@_show_in_interface
+public protocol _UnderscoredProtocol {}