[cxx-interop] Fix two issues with extending nested types across modules.

One fix allows extending nested records in other modules, the other fixes the same issue for namespaces.

lib/ClangImporter/ClangImporter.cpp

@@ -2527,6 +2527,10 @@ static bool isVisibleFromModule(const ClangModuleUnit *ModuleFilter,
   auto *Importer = static_cast<ClangImporter *>(Ctx.getClangModuleLoader());
   auto ClangNode = Importer->getEffectiveClangNode(VD);
 
+  // Decls in the __ObjC bridging header is always visible.
+  if (VD->getModuleContext() == Importer->getImportedHeaderModule())
+    return true;
+
   // Macros can be "redeclared" by putting an equivalent definition in two
   // different modules. (We don't actually check the equivalence.)
   // FIXME: We're also not checking if the redeclaration is in /this/ module.

lib/ClangImporter/ImportDecl.cpp

@@ -2467,6 +2467,11 @@ namespace {
       for (auto redecl : decl->redecls())
         Impl.ImportedDecls[{redecl, getVersion()}] = enumDecl;
 
+      // Because a namespaces's decl context is the bridging header, make sure
+      // we add them to the bridging header lookup table.
+      addEntryToLookupTable(*Impl.BridgingHeaderLookupTable,
+                            const_cast<clang::NamespaceDecl *>(decl),
+                            Impl.getNameImporter());
       return enumDecl;
     }
 

lib/ClangImporter/ImporterImpl.h

@@ -350,9 +350,6 @@ public:
     "<bridging-header-import>";
 
 private:
-  /// The Swift lookup table for the bridging header.
-  std::unique_ptr<SwiftLookupTable> BridgingHeaderLookupTable;
-
   /// The Swift lookup tables, per module.
   ///
   /// Annoyingly, we list this table early so that it gets torn down after
@@ -416,6 +413,9 @@ private:
   llvm::SmallDenseMap<ModuleDecl *, SourceFile *> ClangSwiftAttrSourceFiles;
 
 public:
+  /// The Swift lookup table for the bridging header.
+  std::unique_ptr<SwiftLookupTable> BridgingHeaderLookupTable;
+
   /// Mapping of already-imported declarations.
   llvm::DenseMap<std::pair<const clang::Decl *, Version>, Decl *> ImportedDecls;
 

test/IDE/complete_from_clang_framework.swift

@@ -122,6 +122,9 @@ func testSwiftCompletions(foo: SwiftStruct) {
 // CLANG_BAR-DAG: Decl[GlobalVar]/OtherModule[Bar]:    BAR_MACRO_1[#Int32#]{{; name=.+$}}
 // CLANG_BAR-DAG: Decl[Struct]/OtherModule[Bar]:       SomeItemSet[#SomeItemSet#]
 // CLANG_BAR-DAG: Decl[TypeAlias]/OtherModule[Bar]:    SomeEnvironment[#SomeItemSet#]
+// CLANG_BAR-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: __NSConstantString[#__NSConstantString_tag#]; name=__NSConstantString
+// CLANG_BAR-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: __builtin_ms_va_list[#UnsafeMutablePointer<CChar>#]; name=__builtin_ms_va_list
+// CLANG_BAR-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: __builtin_va_list[#(__va_list_tag)#]; name=__builtin_va_list
 // CLANG_BAR: End completions
 
 // CLANG_BOTH_FOO_BAR: Begin completions
@@ -148,12 +151,15 @@ func testCompleteModuleQualifiedFoo2() {
   Foo#^CLANG_QUAL_FOO_2^#
 // If the number of results below changes, then you need to add a result to the
 // list below.
-// CLANG_QUAL_FOO_2: Begin completions, 76 items
+// CLANG_QUAL_FOO_2: Begin completions, 82 items
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule[Foo]:        .FooClassBase[#FooClassBase#]{{; name=.+$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule[Foo]:        .FooClassDerived[#FooClassDerived#]{{; name=.+$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule[Foo]:        .ClassWithInternalProt[#ClassWithInternalProt#]{{; name=.+$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[Struct]/OtherModule[Foo]:       ._InternalStruct[#_InternalStruct#]
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule[Foo]:        .FooClassPropertyOwnership[#FooClassPropertyOwnership#]{{; name=.+$}}
+// CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: .__NSConstantString[#__NSConstantString_tag#]; name=__NSConstantString
+// CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: .__builtin_ms_va_list[#UnsafeMutablePointer<CChar>#]; name=__builtin_ms_va_list
+// CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: .__builtin_va_list[#(__va_list_tag)#]; name=__builtin_va_list
 // CLANG_QUAL_FOO_2-DAG: Decl[FreeFunction]/OtherModule[Foo]: ._internalTopLevelFunc()[#Void#]
 // CLANG_QUAL_FOO_2-DAG: Decl[Enum]/OtherModule[Foo]:         .FooComparisonResult[#FooComparisonResult#]{{; name=.+$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[FreeFunction]/OtherModule[Foo]: .fooFunc1({#(a): Int32#})[#Int32#]{{; name=.+$}}
@@ -217,6 +223,9 @@ func testCompleteModuleQualifiedFoo2() {
 // CLANG_QUAL_FOO_2-DAG:  Decl[Class]/OtherModule[Foo]:        .FooRepeatedMembers[#FooRepeatedMembers#]{{; name=.+$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule[Foo]: .FooClassWithClassProperties[#FooClassWithClassProperties#];
 // CLANG_QUAL_FOO_2-DAG: Decl[Enum]/OtherModule[Foo]: .SCNFilterMode[#SCNFilterMode#];
+// CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: .__NSConstantString[#__NSConstantString_tag#]; name=__NSConstantString
+// CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: .__builtin_ms_va_list[#UnsafeMutablePointer<CChar>#]; name=__builtin_ms_va_list
+// CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule[__ObjC]: .__builtin_va_list[#(__va_list_tag)#]; name=__builtin_va_list
 // CLANG_QUAL_FOO_2: End completions
 }
 
@@ -224,7 +233,7 @@ func testCompleteModuleQualifiedBar1() {
   Bar.#^CLANG_QUAL_BAR_1^#
 // If the number of results below changes, this is an indication that you need
 // to add a result to the appropriate list.  Do not just bump the number!
-// CLANG_QUAL_BAR_1: Begin completions, 8 items
+// CLANG_QUAL_BAR_1: Begin completions, 11 items
 }
 
 func testCompleteFunctionCall1() {

test/Interop/Cxx/modules/Inputs/bridge-header.h

@@ -0,0 +1,12 @@
+#ifndef TEST_INTEROP_CXX_MODULES_INPUTS_BRIDGE_HEADER_H
+#define TEST_INTEROP_CXX_MODULES_INPUTS_BRIDGE_HEADER_H
+
+struct Parent {
+  struct Child {};
+};
+
+namespace Namespace {
+struct InNamespace {};
+}
+
+#endif // TEST_INTEROP_CXX_MODULES_INPUTS_BRIDGE_HEADER_H

test/Interop/Cxx/modules/Inputs/module.modulemap

@@ -0,0 +1,4 @@
+module Namespace {
+  header "namespace.h"
+  requires cplusplus
+}

test/Interop/Cxx/modules/Inputs/namespace-extension-lib.swift

@@ -0,0 +1,13 @@
+import Namespace
+
+extension Namespace.Parent {
+  public static func test() -> Int { 42 }
+}
+
+extension Namespace.Parent.Child {
+  public static func test() -> Int { 52 }
+}
+
+extension Namespace.NestedNamespace.NestedStruct {
+  public func test() -> Int { 62 }
+}

test/Interop/Cxx/modules/Inputs/namespace.h

@@ -0,0 +1,18 @@
+#ifndef TEST_INTEROP_CXX_MODULES_INPUTS_NAMESPACE_H
+#define TEST_INTEROP_CXX_MODULES_INPUTS_NAMESPACE_H
+
+namespace Namespace {
+
+struct Parent {
+  struct Child {};
+};
+
+namespace NestedNamespace {
+
+struct NestedStruct {};
+
+} // namespace NestedNamespace
+
+} // namespace Namespace
+
+#endif // TEST_INTEROP_CXX_MODULES_INPUTS_NAMESPACE_H

test/Interop/Cxx/modules/Inputs/struct-from-bridge-extension-lib.swift

@@ -0,0 +1,7 @@
+extension Parent.Child {
+  public static func test() -> Int { 42 }
+}
+
+extension Namespace.InNamespace {
+  public func test() -> Int { 52 }
+}

test/Interop/Cxx/modules/use-namespace-extension-lib.swift

@@ -0,0 +1,23 @@
+// RUN: %empty-directory(%t)
+// RUN: cd %t
+// RUN: %target-build-swift    -I %S/Inputs -Xfrontend -enable-cxx-interop %S/Inputs/namespace-extension-lib.swift -emit-module -emit-library -module-name NamespaceExtensionLib
+// RUN: %target-build-swift %s -I %S/Inputs -Xfrontend -enable-cxx-interop -o %t/run -I %t/ -L %t/ -lNamespaceExtensionLib
+// RUN: %target-codesign %t/run
+// RUN: %target-run %t/run
+//
+// REQUIRES: executable_test
+
+import StdlibUnittest
+import Namespace
+import NamespaceExtensionLib
+
+var NamespacesTestSuite = TestSuite("Extension in library on namespace")
+
+NamespacesTestSuite.test("Call functions from extension") {
+  expectEqual(Namespace.Parent.test(), 42)
+  expectEqual(Namespace.Parent.Child.test(), 52)
+  expectEqual(Namespace.NestedNamespace.NestedStruct().test(), 62)
+}
+
+runAllTests()
+

test/Interop/Cxx/modules/use-struct-from-bridge-extension-lib.swift

@@ -0,0 +1,21 @@
+// RUN: %empty-directory(%t)
+// RUN: cd %t
+// RUN: %target-build-swift    -import-objc-header %S/Inputs/bridge-header.h -Xfrontend -enable-cxx-interop %S/Inputs/struct-from-bridge-extension-lib.swift -emit-module -emit-library -module-name BridgeExtensionLib
+// RUN: %target-build-swift %s -import-objc-header %S/Inputs/bridge-header.h -Xfrontend -enable-cxx-interop -o %t/run -I %t/ -L %t/ -lBridgeExtensionLib
+// RUN: %target-codesign %t/run
+// RUN: %target-run %t/run
+//
+// REQUIRES: executable_test
+
+import StdlibUnittest
+import BridgeExtensionLib
+
+var BridgeTestSuite = TestSuite("Extension in library on nested types in bridge header")
+
+BridgeTestSuite.test("Call functions from extension") {
+  expectEqual(Parent.Child.test(), 42)
+  expectEqual(Namespace.InNamespace().test(), 52)
+}
+
+runAllTests()
+

test/Interop/Cxx/namespace/templates-module-interface.swift

@@ -47,10 +47,10 @@
 // CHECK-NEXT: }
 // CHECK-NEXT: typealias ForwardDeclaredClassTemplateOutOfLineChar = TemplatesNS1.TemplatesNS2.__CxxTemplateInstN12TemplatesNS112TemplatesNS237ForwardDeclaredClassTemplateOutOfLineIcEE
 // CHECK-NEXT: enum TemplatesNS4 {
-// CHECK-NEXT:   struct __CxxTemplateInstN12TemplatesNS417HasSpecializationIcEE {
+// CHECK-NEXT:   struct __CxxTemplateInstN12TemplatesNS417HasSpecializationIiEE {
 // CHECK-NEXT:     init()
 // CHECK-NEXT:   }
-// CHECK-NEXT:   struct __CxxTemplateInstN12TemplatesNS417HasSpecializationIiEE {
+// CHECK-NEXT:   struct __CxxTemplateInstN12TemplatesNS417HasSpecializationIcEE {
 // CHECK-NEXT:     init()
 // CHECK-NEXT:   }
 // CHECK-NEXT:   struct HasSpecialization<> {