[Dependency Scanning] Query package-only dependencies from adjacent binary modules when necessary

When '.package.swiftinterface' loading ('-experimental-package-interface-load') is disabled and when '-scanner-module-validation' is disabled, the scanner defaults to locating the non-package textual interface and may specify its adjacent binary module as a valid candidate binary module to use. If said candidate is up-to-date and ends up getting used, and belongs to the same package as the loading Swift source, then the source compilation may attempt to load its package-only dependencies. Since the scanner only parsed the non-package textual interface, those dependencies are not located and specified as inputs to compilation. This change causes the scanner, in such cases, to also lookup package-only dependencies in adjacent binary Swift modules of textual Swift module dependencies, if such dependency belongs to the same package as the source target being scanned.

Resolves rdar://135215789

include/swift/Serialization/SerializedModuleLoader.h

@@ -179,7 +179,18 @@ protected:
   /// Load the module file into a buffer and also collect its module name.
   static std::unique_ptr<llvm::MemoryBuffer>
   getModuleName(ASTContext &Ctx, StringRef modulePath, std::string &Name);
-  
+
+  /// If the module has a package name matching the one
+  /// specified, return a set of package-only imports for this module.
+  static llvm::ErrorOr<llvm::StringSet<>>
+  getMatchingPackageOnlyImportsOfModule(Twine modulePath,
+                                        bool isFramework,
+                                        bool isRequiredOSSAModules,
+                                        StringRef SDKName,
+                                        StringRef packageName,
+                                        llvm::vfs::FileSystem *fileSystem,
+                                        PathObfuscator &recoverer);
+
 public:
   virtual ~SerializedModuleLoaderBase();
   SerializedModuleLoaderBase(const SerializedModuleLoaderBase &) = delete;

lib/Serialization/ScanningLoaders.cpp

@@ -149,6 +149,7 @@ SwiftModuleScanner::scanInterfaceFile(Twine moduleInterfacePath,
   StringRef sdkPath = Ctx.SearchPathOpts.getSDKPath();
   llvm::SmallString<32> modulePath = realModuleName.str();
   llvm::sys::path::replace_extension(modulePath, newExt);
+  auto ScannerPackageName = Ctx.LangOpts.PackageName;
   std::optional<ModuleDependencyInfo> Result;
   std::error_code code = astDelegate.runInSubContext(
       realModuleName.str(), moduleInterfacePath.str(), sdkPath,
@@ -272,6 +273,34 @@ SwiftModuleScanner::scanInterfaceFile(Twine moduleInterfacePath,
                                   &alreadyAddedModules, &Ctx.SourceMgr);
         }
 
+        // If this is a dependency that belongs to the same package, and we have not yet enabled Package Textual interfaces,
+        // scan the adjacent binary module for package dependencies.
+        if (!ScannerPackageName.empty() &&
+            !Ctx.LangOpts.EnablePackageInterfaceLoad) {
+           auto adjacentBinaryModule = std::find_if(
+               compiledCandidates.begin(), compiledCandidates.end(),
+               [moduleInterfacePath](const std::string &candidate) {
+                 return llvm::sys::path::parent_path(candidate) ==
+                        llvm::sys::path::parent_path(moduleInterfacePath.str());
+               });
+
+           if (adjacentBinaryModule != compiledCandidates.end()) {
+             auto adjacentBinaryModulePackageOnlyImports = getMatchingPackageOnlyImportsOfModule(
+                  *adjacentBinaryModule, isFramework,
+                  isRequiredOSSAModules(), Ctx.LangOpts.SDKName,
+                  ScannerPackageName, Ctx.SourceMgr.getFileSystem().get(),
+                  Ctx.SearchPathOpts.DeserializedPathRecoverer);
+
+             if (!adjacentBinaryModulePackageOnlyImports)
+               return adjacentBinaryModulePackageOnlyImports.getError();
+
+             for (const auto &requiredImport : *adjacentBinaryModulePackageOnlyImports)
+               if (!alreadyAddedModules.contains(requiredImport.getKey()))
+                 Result->addModuleImport(requiredImport.getKey(),
+                                         &alreadyAddedModules);
+           }
+         }
+
         return std::error_code();
       });
 

lib/Serialization/SerializedModuleLoader.cpp

@@ -301,6 +301,45 @@ SerializedModuleLoaderBase::getModuleName(ASTContext &Ctx, StringRef modulePath,
   return ModuleFile::getModuleName(Ctx, modulePath, Name);
 }
 
+llvm::ErrorOr<llvm::StringSet<>>
+SerializedModuleLoaderBase::getMatchingPackageOnlyImportsOfModule(
+    Twine modulePath, bool isFramework, bool isRequiredOSSAModules,
+    StringRef SDKName, StringRef packageName, llvm::vfs::FileSystem *fileSystem,
+    PathObfuscator &recoverer) {
+  auto moduleBuf = fileSystem->getBufferForFile(modulePath);
+  if (!moduleBuf)
+    return moduleBuf.getError();
+
+  llvm::StringSet<> importedModuleNames;
+  // Load the module file without validation.
+  std::shared_ptr<const ModuleFileSharedCore> loadedModuleFile;
+  serialization::ValidationInfo loadInfo = ModuleFileSharedCore::load(
+      "", "", std::move(moduleBuf.get()), nullptr, nullptr, isFramework,
+      isRequiredOSSAModules, SDKName, recoverer, loadedModuleFile);
+
+  if (loadedModuleFile->getModulePackageName() != packageName)
+    return importedModuleNames;
+
+  for (const auto &dependency : loadedModuleFile->getDependencies()) {
+    if (dependency.isHeader())
+      continue;
+    if (!dependency.isPackageOnly())
+      continue;
+
+    // Find the top-level module name.
+    auto modulePathStr = dependency.getPrettyPrintedPath();
+    StringRef moduleName = modulePathStr;
+    auto dotPos = moduleName.find('.');
+    if (dotPos != std::string::npos)
+      moduleName = moduleName.slice(0, dotPos);
+
+    importedModuleNames.insert(moduleName);
+  }
+
+  return importedModuleNames;
+}
+
+
 std::error_code
 SerializedModuleLoaderBase::openModuleSourceInfoFileIfPresent(
     ImportPath::Element ModuleID,

test/ScanDependencies/package_deps_of_same_package_imports.swift

@@ -0,0 +1,40 @@
+// REQUIRES: executable_test
+// REQUIRES: objc_interop
+// RUN: %empty-directory(%t)
+// RUN: %empty-directory(%t/clang-module-cache)
+// RUN: %empty-directory(%t/Foo.swiftmodule)
+// RUN: %empty-directory(%t/Bar.swiftmodule)
+// RUN: split-file %s %t
+
+// Step 1: build Bar swift interface and swift module side by side
+// RUN: %target-swift-frontend -emit-module %t/Bar.swift -emit-module-path %t/Bar.swiftmodule/%target-swiftmodule-name -module-name Bar -emit-module-interface-path %t/Bar.swiftmodule/%target-swiftinterface-name -I %S/Inputs/CHeaders -I %S/Inputs/Swift
+
+// Step 2: build Foo swift interface and swift module side by side belonging to package 'Test'
+// RUN: %target-swift-frontend -emit-module %t/Foo.swift -emit-module-path %t/Foo.swiftmodule/%target-swiftmodule-name -module-name Foo -emit-module-interface-path %t/Foo.swiftmodule/%target-swiftinterface-name -I %S/Inputs/CHeaders -I %S/Inputs/Swift -I %t -package-name Test
+
+// Step 3: scan dependencies with '-no-scanner-module-validation' and '-package-name Test'
+// RUN: %target-swift-frontend -scan-dependencies %t/Client.swift -o %t/deps.json -no-scanner-module-validation -I %t -sdk %t -prebuilt-module-cache-path %t/clang-module-cache -I %S/Inputs/CHeaders -I %S/Inputs/Swift -package-name Test
+// Step 4: Ensure that same-package scan can see package-only dependencies
+// RUN: %FileCheck %s --input-file=%t/deps.json --check-prefix CHECK-SAME-PACKAGE
+
+// Step 5: scan dependencies with '-no-scanner-module-validation' and no package name
+// RUN: %target-swift-frontend -scan-dependencies %t/Client.swift -o %t/deps_no_package.json -no-scanner-module-validation -I %t -sdk %t -prebuilt-module-cache-path %t/clang-module-cache -I %S/Inputs/CHeaders -I %S/Inputs/Swift
+// Step 6: Ensure that non-same-package scan can not see package-only dependencies
+// RUN: %FileCheck %s --input-file=%t/deps_no_package.json --check-prefix CHECK-NO-PACKAGE
+
+
+// CHECK-SAME-PACKAGE: "swift": "Bar"
+// CHECK-NO-PACKAGE-NOT: "swift": "Bar"
+
+//--- Bar.swift
+enum PubEnum {
+  case red, green
+}
+
+//--- Foo.swift
+package import Bar
+
+//--- Client.swift
+import Foo
+
+