Add back the dummy DWARFImporter test to lldb-moduleimport-test.

include/swift/ClangImporter/ClangImporter.h

@@ -128,6 +128,9 @@ class ClangImporter final : public ClangModuleLoader {
 
   ~ClangImporter();
 
+  /// Only to be used by lldb-moduleimport-test.
+  void setDWARFImporterDelegate(DWARFImporterDelegate &delegate);
+
   /// Create a new clang::DependencyCollector customized to
   /// ClangImporter's specific uses.
   static std::shared_ptr<clang::DependencyCollector>

lib/ClangImporter/DWARFImporter.cpp

@@ -176,3 +176,12 @@ void ClangImporter::Implementation::lookupTypeDeclDWARF(
       receiver(importedType);
   }
 }
+
+void ClangImporter::setDWARFImporterDelegate(DWARFImporterDelegate &delegate) {
+  Impl.setDWARFImporterDelegate(delegate);
+}
+
+void ClangImporter::Implementation::setDWARFImporterDelegate(
+    DWARFImporterDelegate &delegate) {
+  DWARFImporter = &delegate;
+}

lib/ClangImporter/ImporterImpl.h

@@ -606,14 +606,19 @@ class LLVM_LIBRARY_VISIBILITY ClangImporter::Implementation
 private:
   /// The DWARF importer delegate, if installed.
   DWARFImporterDelegate *DWARFImporter = nullptr;
+public:
+  /// Only used for testing.
+  void setDWARFImporterDelegate(DWARFImporterDelegate &delegate);
+
+private:
   /// The list of Clang modules found in the debug info.
   llvm::DenseMap<Identifier, LoadedFile *> DWARFModuleUnits;
-
 public:
   /// "Import" a module from debug info. Because debug info types are read on
   /// demand, this doesn't really do any work.
   ModuleDecl *loadModuleDWARF(SourceLoc importLoc,
                               ArrayRef<std::pair<Identifier, SourceLoc>> path);
+
 
   void recordImplicitUnwrapForDecl(Decl *decl, bool isIUO) {
 #if !defined(NDEBUG)

test/DWARFImporter/Inputs/module.modulemap

@@ -0,0 +1,4 @@
+module ObjCModule {
+  header "objc-header.h"
+  export *
+}

test/DWARFImporter/Inputs/objc-header.h

@@ -0,0 +1,7 @@
+struct Point {
+  int x, y;
+};
+
+@interface ObjCClass
+- (instancetype)init;
+@end

test/DWARFImporter/basic.swift

@@ -0,0 +1,32 @@
+// REQUIRES: executable_test
+// REQUIRES: objc_interop
+
+// RUN: %empty-directory(%t)
+
+// RUN: cp %S/Inputs/objc-header.h %S/Inputs/module.modulemap  %t
+// RUN: %target-build-swift -emit-executable %s -g -o %t/a.out \
+// RUN:   -module-name basic -emit-module -I%t
+//        -DOBJC -module-name basic
+// RUN: %lldb-moduleimport-test -verbose -dump-module %t/a.out | %FileCheck %s
+
+// RUN: rm %t/objc-header.h
+// RUN: %lldb-moduleimport-test -verbose -dump-module %t/a.out \
+// RUN:    | %FileCheck %s --check-prefix=FAIL
+
+// RUN: %lldb-moduleimport-test -verbose -dump-module %t/a.out \
+// RUN:    -dummy-dwarfimporter | %FileCheck %s --check-prefix=SWIFTONLY
+
+// CHECK: Importing basic... ok!
+// FAIL: Importing basic... ok!
+// SWIFTONLY: Importing basic... ok!
+import ObjCModule
+
+let pureSwift = Int32(42)
+// FAIL-NOT:  var_decl
+// CHECK:     var_decl "pureSwift" {{.*}} type='Int32'
+// SWIFTONLY: var_decl "pureSwift" {{.*}} type='Int32' 
+
+let point = Point(x: 1, y: 2)
+// CHECK:     var_decl "point" {{.*}} type='Point'
+// SWIFTONLY-NOT: var_decl "point"
+

tools/lldb-moduleimport-test/lldb-moduleimport-test.cpp

@@ -220,6 +220,10 @@ int main(int argc, char **argv) {
       desc("The directory that holds the compiler resource files"),
       cat(Visible));
 
+  opt<bool> DummyDWARFImporter(
+      "dummy-dwarfimporter",
+      desc("Install a dummy DWARFImporterDelegate"), cat(Visible));
+
   ParseCommandLineOptions(argc, argv);
 
   // Unregister our options so they don't interfere with the command line
@@ -296,6 +300,13 @@ int main(int argc, char **argv) {
     return 1;
   }
 
+  swift::DWARFImporterDelegate dummyDWARFImporter;
+  if (DummyDWARFImporter) {
+    auto *ClangImporter = static_cast<swift::ClangImporter *>(
+        CI.getASTContext().getClangModuleLoader());
+    ClangImporter->setDWARFImporterDelegate(dummyDWARFImporter);
+  }
+
   for (auto &Module : Modules)
     if (!parseASTSection(*CI.getMemoryBufferSerializedModuleLoader(),
                          StringRef(Module.first, Module.second), modules)) {