Merge pull request #23511 from jrose-apple/test-tube

Treat "lookup into immediately imported modules" as a special case

rdar://problem/48890959

Author: jrose-apple

lib/AST/ModuleNameLookup.cpp

@@ -220,32 +220,37 @@ void NameBinder::addImport(
       assert(!M->getFiles().empty() &&
              isa<ClangModuleUnit>(M->getFiles().front()));
       topLevelModule = M;
+    } else if (topLevelModule == SF.getParentModule()) {
+      // This can happen when compiling a mixed-source framework (or overlay)
+      // that imports a submodule of its C part.
+      topLevelModule = nullptr;
     }
   }
 
   auto *testableAttr = ID->getAttrs().getAttribute<TestableAttr>();
-  if (testableAttr && !topLevelModule->isTestingEnabled() &&
+  if (testableAttr && topLevelModule &&
+      !topLevelModule->isTestingEnabled() &&
       !topLevelModule->isNonSwiftModule() &&
       Context.LangOpts.EnableTestableAttrRequiresTestableModule) {
     diagnose(ID->getModulePath().front().second, diag::module_not_testable,
-             topLevelModule->getName());
+             ID->getModulePath().front().first);
     testableAttr->setInvalid();
   }
 
   auto *privateImportAttr = ID->getAttrs().getAttribute<PrivateImportAttr>();
   StringRef privateImportFileName;
   if (privateImportAttr) {
-    if (!topLevelModule->arePrivateImportsEnabled()) {
+    if (!topLevelModule || !topLevelModule->arePrivateImportsEnabled()) {
       diagnose(ID->getModulePath().front().second,
                diag::module_not_compiled_for_private_import,
-               topLevelModule->getName());
+               ID->getModulePath().front().first);
       privateImportAttr->setInvalid();
     } else {
       privateImportFileName = privateImportAttr->getSourceFile();
     }
   }
 
-  if (SF.getParentModule()->isResilient() &&
+  if (SF.getParentModule()->isResilient() && topLevelModule &&
       !topLevelModule->isResilient() &&
       !topLevelModule->isNonSwiftModule() &&
       !ID->getAttrs().hasAttribute<ImplementationOnlyAttr>()) {
@@ -277,7 +282,7 @@ void NameBinder::addImport(
   imports.push_back(SourceFile::ImportedModuleDesc(
       {ID->getDeclPath(), M}, options, privateImportFileName));
 
-  if (topLevelModule != M)
+  if (topLevelModule && topLevelModule != M)
     imports.push_back(SourceFile::ImportedModuleDesc(
         {ID->getDeclPath(), topLevelModule}, options, privateImportFileName));
 

lib/Sema/NameBinding.cpp

@@ -0,0 +1 @@
+extern void topLevel();

test/ClangImporter/MixedSource/Inputs/submodule/Mixed.h

@@ -0,0 +1 @@
+extern void fromSubmodule();

test/ClangImporter/MixedSource/Inputs/submodule/Submodule.h

@@ -0,0 +1,9 @@
+module Mixed {
+  header "Mixed.h"
+  export *
+
+  explicit module Submodule {
+    header "Submodule.h"
+    export *
+  }
+}

test/ClangImporter/MixedSource/Inputs/submodule/module.modulemap

@@ -0,0 +1,9 @@
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -typecheck -verify -I %S/Inputs/submodule -module-name Mixed %s
+
+@_exported import Mixed
+@_exported import Mixed.Submodule
+
+func test() {
+  _ = topLevel()
+  _ = fromSubmodule()
+}

test/ClangImporter/MixedSource/submodule.swift

@@ -0,0 +1 @@
+internal func t1() {}

test/NameBinding/Inputs/TestableVersusIndirect1.swift

@@ -0,0 +1 @@
+internal func t2() {}

test/NameBinding/Inputs/TestableVersusIndirect2.swift

@@ -0,0 +1,2 @@
+@_exported import TestableVersusIndirect1
+@_exported import TestableVersusIndirect2

test/NameBinding/Inputs/TestableVersusIndirectImporter.swift

@@ -0,0 +1,12 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-frontend -emit-module -enable-testing -o %t/TestableVersusIndirect1.swiftmodule %S/Inputs/TestableVersusIndirect1.swift
+// RUN: %target-swift-frontend -emit-module -enable-testing -o %t/TestableVersusIndirect2.swiftmodule %S/Inputs/TestableVersusIndirect2.swift
+// RUN: %target-swift-frontend -emit-module -I %t -o %t/TestableVersusIndirectImporter.swiftmodule %S/Inputs/TestableVersusIndirectImporter.swift
+// RUN: %target-swift-frontend -typecheck -I %t %s
+
+@testable import TestableVersusIndirect1
+import TestableVersusIndirectImporter
+@testable import TestableVersusIndirect2
+
+t1()
+t2()