1 files changed, 94 insertions, 0 deletions
diff --git a/test/CXX/module/module.interface/p2.cpp b/test/CXX/module/module.interface/p2.cpp
new file mode 100644
index 0000000000..0a6f8c2aad
--- /dev/null
+++ b/test/CXX/module/module.interface/p2.cpp
@@ -0,0 +1,94 @@
+// RUN: rm -rf %t
+// RUN: mkdir -p %t
+// RUN: %clang_cc1 -std=c++2a -x c++-header %S/Inputs/header.h -emit-header-module -fmodule-name=FIXME -o %t/h.pcm
+// RUN: %clang_cc1 -std=c++2a %s -DX_INTERFACE -emit-module-interface -o %t/x.pcm
+// RUN: %clang_cc1 -std=c++2a %s -DY_INTERFACE -emit-module-interface -o %t/y.pcm
+// RUN: %clang_cc1 -std=c++2a %s -DINTERFACE -fmodule-file=%t/x.pcm -fmodule-file=%t/y.pcm -emit-module-interface -o %t/m.pcm
+// RUN: %clang_cc1 -std=c++2a %s -DIMPLEMENTATION -I%S/Inputs -fmodule-file=%t/h.pcm -fmodule-file=%t/m.pcm -verify
+// RUN: %clang_cc1 -std=c++2a %s -DUSER -I%S/Inputs -fmodule-file=%t/h.pcm -fmodule-file=%t/m.pcm -verify
+
+#if defined(X_INTERFACE)
+export module X;
+export int x;
+
+#elif defined(Y_INTERFACE)
+export module Y;
+export int y;
+
+#elif defined(INTERFACE)
+export module p2;
+export import X;
+import Y; // not exported
+
+namespace A {
+  int f();
+  export int g();
+  int h();
+  namespace inner {}
+}
+export namespace B {
+  namespace inner {}
+}
+namespace B {
+  int f();
+}
+namespace C {}
+namespace D { int f(); }
+export namespace D {}
+
+#elif defined(IMPLEMENTATION)
+module p2;
+import "header.h";
+
+// Per [basic.scope.namespace]/2.3, exportedness has no impact on visibility
+// within the same module.
+//
+// expected-no-diagnostics
+
+void use() {
+  A::f();
+  A::g();
+  A::h();
+  using namespace A::inner;
+
+  using namespace B;
+  using namespace B::inner;
+  B::f();
+  f();
+
+  using namespace C;
+
+  D::f();
+}
+
+int use_header() { return foo + bar::baz(); }
+
+#elif defined(USER)
+import p2;
+import "header.h";
+
+void use() {
+  // namespace A is implicitly exported by the export of A::g.
+  A::f(); // expected-error {{no member named 'f' in namespace 'A'}}
+  A::g();
+  A::h(); // expected-error {{no member named 'h' in namespace 'A'}}
+  using namespace A::inner; // expected-error {{expected namespace name}}
+
+  // namespace B and B::inner are explicitly exported
+  using namespace B;
+  using namespace B::inner;
+  B::f(); // expected-error {{no member named 'f' in namespace 'B'}}
+  f(); // expected-error {{undeclared identifier 'f'}}
+
+  // namespace C is not exported
+  using namespace C; // expected-error {{expected namespace name}}
+
+  // namespace D is exported, but D::f is not
+  D::f(); // expected-error {{no member named 'f' in namespace 'D'}}
+}
+
+int use_header() { return foo + bar::baz(); }
+
+#else
+#error unknown mode
+#endif