Basic: Split out DirectoryEntry.h, NFC

[dexonsmith]

Summary

Move DirectoryEntry and DirectoryEntryRef into their own header,
similar to the creation of FileEntry.h. No functionality change here,
just preparing to include it in more places to allow wider adoption of
DirectoryEntryRef without requiring all of FileManager.h.

clang/include/clang/Basic/DirectoryEntry.h

+//===- clang/Basic/DirectoryEntry.h - Directory references ------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Defines interfaces for clang::DirectoryEntry and clang::DirectoryEntryRef.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_BASIC_DIRECTORYENTRY_H
+#define LLVM_CLANG_BASIC_DIRECTORYENTRY_H
+
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/ErrorOr.h"
+
+namespace clang {
+
+/// Cached information about one directory (either on disk or in
+/// the virtual file system).
+class DirectoryEntry {
+  friend class FileManager;
+
+  // FIXME: We should not be storing a directory entry name here.
+  StringRef Name; // Name of the directory.
+
+public:
+  StringRef getName() const { return Name; }
+};
+
+/// A reference to a \c DirectoryEntry  that includes the name of the directory
+/// as it was accessed by the FileManager's client.
+class DirectoryEntryRef {
+public:
+  const DirectoryEntry &getDirEntry() const { return *Entry->getValue(); }
+
+  StringRef getName() const { return Entry->getKey(); }
+
+private:
+  friend class FileManager;
+
+  DirectoryEntryRef(
+      llvm::StringMapEntry<llvm::ErrorOr<DirectoryEntry &>> *Entry)
+      : Entry(Entry) {}
+
+  const llvm::StringMapEntry<llvm::ErrorOr<DirectoryEntry &>> *Entry;
+};
+
+} // end namespace clang
+
+#endif // LLVM_CLANG_BASIC_DIRECTORYENTRY_H

clang/include/clang/Basic/FileManager.h

 //===--- FileManager.h - File System Probing and Caching --------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
 /// Defines the clang::FileManager interface and associated types.
 ///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_BASIC_FILEMANAGER_H
 #define LLVM_CLANG_BASIC_FILEMANAGER_H
 
+#include "clang/Basic/DirectoryEntry.h"
 #include "clang/Basic/FileEntry.h"
 #include "clang/Basic/FileSystemOptions.h"
 #include "clang/Basic/LLVM.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/IntrusiveRefCntPtr.h"
 #include "llvm/ADT/PointerUnion.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringMap.h"

 class MemoryBuffer;
 
 } // end namespace llvm
 
 namespace clang {
 
 class FileSystemStatCache;
 
-/// Cached information about one directory (either on disk or in
-/// the virtual file system).
-class DirectoryEntry {
-  friend class FileManager;
-
-  // FIXME: We should not be storing a directory entry name here.
-  StringRef Name; // Name of the directory.
-
-public:
-  StringRef getName() const { return Name; }
-};
-
-/// A reference to a \c DirectoryEntry  that includes the name of the directory
-/// as it was accessed by the FileManager's client.
-class DirectoryEntryRef {
-public:
-  const DirectoryEntry &getDirEntry() const { return *Entry->getValue(); }
-
-  StringRef getName() const { return Entry->getKey(); }
-
-private:
-  friend class FileManager;
-
-  DirectoryEntryRef(
-      llvm::StringMapEntry<llvm::ErrorOr<DirectoryEntry &>> *Entry)
-      : Entry(Entry) {}
-
-  const llvm::StringMapEntry<llvm::ErrorOr<DirectoryEntry &>> *Entry;
-};
-
 /// Implements support for file system lookup, file system caching,
 /// and directory search management.
 ///
 /// This also handles more advanced properties, such as uniquing files based
 /// on "inode", so that a file with two names (e.g. symlinked) will be treated
 /// as a single file.
 ///
 class FileManager : public RefCountedBase<FileManager> {