Revert #76244.

Partially resolves rdar://139236053.

Author: tshortli

include/swift/Frontend/ModuleInterfaceSupport.h

@@ -72,6 +72,10 @@ struct ModuleInterfaceOptions {
   /// Print imports that are missing from the source and used in API.
   bool PrintMissingImports = true;
 
+  /// If true, package-name flag is not printed in either public or private
+  /// interface file.
+  bool DisablePackageNameForNonPackageInterface = false;
+
   /// Intentionally print invalid syntax into the file.
   bool DebugPrintInvalidSyntax = false;
 

include/swift/Option/Options.td

@@ -761,11 +761,7 @@ def disable_bridging_pch : Flag<["-"], "disable-bridging-pch">,
 def disable_print_package_name_for_non_package_interface :
   Flag<["-"], "disable-print-package-name-for-non-package-interface">,
   Flags<[FrontendOption, NoDriverOption, HelpHidden]>,
-  HelpText<"No op; package name is only printed in package interface by default">;
-def print_package_name_in_non_package_interface :
-  Flag<["-"], "print-package-name-in-non-package-interface">,
-  Flags<[FrontendOption, NoDriverOption, HelpHidden]>,
-  HelpText<"Print package name in public or private interface">;
+  HelpText<"Disable adding package name to public or private interface">;
 
 def lto : Joined<["-"], "lto=">,
   Flags<[FrontendOption, NoInteractiveOption]>,

lib/Frontend/CompilerInvocation.cpp

@@ -524,6 +524,7 @@ static void ParseModuleInterfaceArgs(ModuleInterfaceOptions &Opts,
   Opts.PrintMissingImports =
     !Args.hasArg(OPT_disable_print_missing_imports_in_module_interface);
   Opts.ABIComments = Args.hasArg(OPT_abi_comments_in_module_interface);
+  Opts.DisablePackageNameForNonPackageInterface |= Args.hasArg(OPT_disable_print_package_name_for_non_package_interface);
 
   if (const Arg *A = Args.getLastArg(OPT_library_level)) {
     StringRef contents = A->getValue();
@@ -555,8 +556,8 @@ static bool ShouldIncludeModuleInterfaceArg(const Arg *A) {
 
 static bool IsPackageInterfaceFlag(const Arg *A, ArgList &Args) {
   return A->getOption().matches(options::OPT_package_name) &&
-         !Args.hasArg(
-             options::OPT_print_package_name_in_non_package_interface);
+         Args.hasArg(
+             options::OPT_disable_print_package_name_for_non_package_interface);
 }
 
 static bool IsPrivateInterfaceFlag(const Arg *A, ArgList &Args) {

test/ModuleInterface/package_interface.swift

@@ -23,6 +23,7 @@ public enum PubEnum {
   case red, green
 }
 
+// CHECK: -package-name barpkg
 // CHECK: public enum PubEnum {
 // CHECK:   case red, green
 // CHECK:   public static func == (a: Bar.PubEnum, b: Bar.PubEnum) -> Swift.Bool

test/ModuleInterface/print_package_name_in_non_package_interface.swift renamed to test/ModuleInterface/package_interface_disable_package_name.swift

@@ -1,11 +1,12 @@
 // RUN: %empty-directory(%t)
 // RUN: split-file %s %t
 
-/// By default, package-name is only printed in package interface
+/// Do not print package-name for public or private interfaces
 // RUN: %target-build-swift -emit-module %t/Bar.swift -I %t \
 // RUN:   -module-name Bar -package-name foopkg \
 // RUN:   -enable-library-evolution -swift-version 6 \
 // RUN:   -package-name barpkg \
+// RUN:   -Xfrontend -disable-print-package-name-for-non-package-interface \
 // RUN:   -emit-module-interface-path %t/Bar.swiftinterface \
 // RUN:   -emit-private-module-interface-path %t/Bar.private.swiftinterface \
 // RUN:   -emit-package-module-interface-path %t/Bar.package.swiftinterface
@@ -50,14 +51,11 @@
 // RUN: rm -rf %t/Bar.private.swiftinterface
 // RUN: rm -rf %t/Bar.package.swiftinterface
 
-/// Print -package-name in public or private interface.
-/// Note the order of arguments differs across old/new driver, so force old
-/// driver for now.
+/// By default, -package-name is printed in all interfaces.
 // RUN: env SWIFT_USE_OLD_DRIVER=1 %target-build-swift \
 // RUN:   -emit-module %t/Bar.swift -I %t \
 // RUN:   -module-name Bar -package-name barpkg \
 // RUN:   -enable-library-evolution -swift-version 6 \
-// RUN:   -Xfrontend -print-package-name-in-non-package-interface \
 // RUN:   -emit-module-interface-path %t/Bar.swiftinterface \
 // RUN:   -emit-private-module-interface-path %t/Bar.private.swiftinterface \
 // RUN:   -emit-package-module-interface-path %t/Bar.package.swiftinterface