// RUN: rm -rf %t
// RUN: mkdir -p %t
// RUN: split-file %s %t
//
// RUN: %clang_cc1 -std=c++20 -x c++-header %S/Inputs/header.h -emit-header-unit -o %t/h.pcm
// RUN: %clang_cc1 -std=c++20 %t/x.cppm -emit-module-interface -o %t/x.pcm
// RUN: %clang_cc1 -std=c++20 %t/y.cppm -emit-module-interface -o %t/y.pcm
// RUN: %clang_cc1 -std=c++20 %t/interface.cppm -fmodule-file=X=%t/x.pcm -fmodule-file=Y=%t/y.pcm -emit-module-interface -o %t/m.pcm
// RUN: %clang_cc1 -std=c++20 %t/impl.cppm -I%S/Inputs -fmodule-file=%t/h.pcm \
// RUN:   -fmodule-file=X=%t/x.pcm -fmodule-file=Y=%t/y.pcm -fmodule-file=p2=%t/m.pcm -verify \
// RUN:   -Wno-experimental-header-units
// RUN: %clang_cc1 -std=c++20 %t/user.cppm -I%S/Inputs -fmodule-file=%t/h.pcm -fmodule-file=p2=%t/m.pcm \
// RUN:   -fmodule-file=X=%t/x.pcm -fmodule-file=Y=%t/y.pcm -Wno-experimental-header-units -verify

//--- x.cppm
export module X;
export int x;

//--- y.cppm
export module Y;
export int y;

//--- interface.cppm
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 {}

//--- impl.cppm
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(); }

//--- user.cppm
import p2;
import "header.h";

void use() {
  // namespace A is implicitly exported by the export of A::g.
  A::f(); // expected-error {{declaration of 'f' must be imported from module 'p2' before it is required}}
          // expected-note@* {{declaration here is not visible}}
  A::g();
  A::h();                   // expected-error {{declaration of 'h' must be imported from module 'p2' before it is required}}
                            // expected-note@* {{declaration here is not visible}}
  using namespace A::inner; // expected-error {{declaration of 'inner' must be imported from module 'p2' before it is required}}

  // namespace B and B::inner are explicitly exported
  using namespace B;
  using namespace B::inner;
  B::f(); // expected-error {{declaration of 'f' must be imported from module 'p2' before it is required}}
          // expected-note@* {{declaration here is not visible}}
  f();    // expected-error {{declaration of 'f' must be imported from module 'p2' before it is required}}
          // expected-note@* {{declaration here is not visible}}

  // namespace C is not exported
  using namespace C; // expected-error {{declaration of 'C' must be imported from module 'p2' before it is required}}

  // namespace D is exported, but D::f is not
  D::f(); // expected-error {{declaration of 'f' must be imported from module 'p2' before it is required}}
          // expected-note@* {{declaration here is not visible}}
}

int use_header() { return foo + bar::baz(); }