Use FileEntryRef for PPCallbacks::FileSkipped

This fixes the issue where a filename dependendency was missing if the file that
was skipped was included through a symlink in an earlier run, if the file
manager was reused between runs.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@369998 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Lex/PPCallbacks.h

@@ -57,10 +57,9 @@ public:
   /// \param FilenameTok The file name token in \#include "FileName" directive
   /// or macro expanded file name token from \#include MACRO(PARAMS) directive.
   /// Note that FilenameTok contains corresponding quotes/angles symbols.
-  virtual void FileSkipped(const FileEntry &SkippedFile,
+  virtual void FileSkipped(const FileEntryRef &SkippedFile,
                            const Token &FilenameTok,
-                           SrcMgr::CharacteristicKind FileType) {
-  }
+                           SrcMgr::CharacteristicKind FileType) {}
 
   /// Callback invoked whenever an inclusion directive results in a
   /// file-not-found error.
@@ -390,8 +389,7 @@ public:
     Second->FileChanged(Loc, Reason, FileType, PrevFID);
   }
 
-  void FileSkipped(const FileEntry &SkippedFile,
-                   const Token &FilenameTok,
+  void FileSkipped(const FileEntryRef &SkippedFile, const Token &FilenameTok,
                    SrcMgr::CharacteristicKind FileType) override {
     First->FileSkipped(SkippedFile, FilenameTok, FileType);
     Second->FileSkipped(SkippedFile, FilenameTok, FileType);

lib/Frontend/DependencyFile.cpp

@@ -59,7 +59,7 @@ struct DepCollectorPPCallbacks : public PPCallbacks {
                                     /*IsModuleFile*/false, /*IsMissing*/false);
   }
 
-  void FileSkipped(const FileEntry &SkippedFile, const Token &FilenameTok,
+  void FileSkipped(const FileEntryRef &SkippedFile, const Token &FilenameTok,
                    SrcMgr::CharacteristicKind FileType) override {
     StringRef Filename =
         llvm::sys::path::remove_leading_dotslash(SkippedFile.getName());

lib/Frontend/Rewrite/InclusionRewriter.cpp

@@ -70,7 +70,7 @@ private:
   void FileChanged(SourceLocation Loc, FileChangeReason Reason,
                    SrcMgr::CharacteristicKind FileType,
                    FileID PrevFID) override;
-  void FileSkipped(const FileEntry &SkippedFile, const Token &FilenameTok,
+  void FileSkipped(const FileEntryRef &SkippedFile, const Token &FilenameTok,
                    SrcMgr::CharacteristicKind FileType) override;
   void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
                           StringRef FileName, bool IsAngled,
@@ -169,8 +169,8 @@ void InclusionRewriter::FileChanged(SourceLocation Loc,
 
 /// Called whenever an inclusion is skipped due to canonical header protection
 /// macros.
-void InclusionRewriter::FileSkipped(const FileEntry &/*SkippedFile*/,
-                                    const Token &/*FilenameTok*/,
+void InclusionRewriter::FileSkipped(const FileEntryRef & /*SkippedFile*/,
+                                    const Token & /*FilenameTok*/,
                                     SrcMgr::CharacteristicKind /*FileType*/) {
   assert(LastInclusionLocation.isValid() &&
          "A file, that wasn't found via an inclusion directive, was skipped");

lib/Lex/PPDirectives.cpp

@@ -2029,7 +2029,7 @@ Preprocessor::ImportAction Preprocessor::HandleHeaderIncludeOrImport(
         RelativePath, Action == Import ? SuggestedModule.getModule() : nullptr,
         FileCharacter);
     if (Action == Skip && File)
-      Callbacks->FileSkipped(File->getFileEntry(), FilenameTok, FileCharacter);
+      Callbacks->FileSkipped(*File, FilenameTok, FileCharacter);
   }
 
   if (!File)

unittests/Tooling/DependencyScannerTest.cpp

@@ -37,7 +37,8 @@ public:
       : DependencyFileGenerator(Opts), Deps(Deps) {}
 
   void finishedMainFile(DiagnosticsEngine &Diags) override {
-    Deps = getDependencies();
+    auto NewDeps = getDependencies();
+    Deps.insert(Deps.end(), NewDeps.begin(), NewDeps.end());
   }
 
 private:
@@ -121,5 +122,44 @@ TEST(DependencyScanner, ScanDepsReuseFilemanager) {
   EXPECT_EQ(Files.getNumUniqueRealFiles(), 2u);
 }
 
+TEST(DependencyScanner, ScanDepsReuseFilemanagerSkippedFile) {
+  std::vector<std::string> Compilation = {"-c", "-E", "-MT", "test.cpp.o"};
+  StringRef CWD = "/root";
+  FixedCompilationDatabase CDB(CWD, Compilation);
+
+  auto VFS = new llvm::vfs::InMemoryFileSystem();
+  VFS->setCurrentWorkingDirectory(CWD);
+  auto Sept = llvm::sys::path::get_separator();
+  std::string HeaderPath = llvm::formatv("{0}root{0}header.h", Sept);
+  std::string SymlinkPath = llvm::formatv("{0}root{0}symlink.h", Sept);
+  std::string TestPath = llvm::formatv("{0}root{0}test.cpp", Sept);
+  std::string Test2Path = llvm::formatv("{0}root{0}test2.cpp", Sept);
+
+  VFS->addFile(HeaderPath, 0,
+               llvm::MemoryBuffer::getMemBuffer("#pragma once\n"));
+  VFS->addHardLink(SymlinkPath, HeaderPath);
+  VFS->addFile(TestPath, 0,
+               llvm::MemoryBuffer::getMemBuffer(
+                   "#include \"header.h\"\n#include \"symlink.h\"\n"));
+  VFS->addFile(Test2Path, 0,
+               llvm::MemoryBuffer::getMemBuffer(
+                   "#include \"symlink.h\"\n#include \"header.h\"\n"));
+
+  ClangTool Tool(CDB, {"test.cpp", "test2.cpp"},
+                 std::make_shared<PCHContainerOperations>(), VFS);
+  Tool.clearArgumentsAdjusters();
+  std::vector<std::string> Deps;
+  TestDependencyScanningAction Action(Deps);
+  Tool.run(&Action);
+  using llvm::sys::path::convert_to_slash;
+  ASSERT_EQ(Deps.size(), 6u);
+  EXPECT_EQ(convert_to_slash(Deps[0]), "/root/test.cpp");
+  EXPECT_EQ(convert_to_slash(Deps[1]), "/root/header.h");
+  EXPECT_EQ(convert_to_slash(Deps[2]), "/root/symlink.h");
+  EXPECT_EQ(convert_to_slash(Deps[3]), "/root/test2.cpp");
+  EXPECT_EQ(convert_to_slash(Deps[4]), "/root/symlink.h");
+  EXPECT_EQ(convert_to_slash(Deps[5]), "/root/header.h");
+}
+
 } // end namespace tooling
 } // end namespace clang