clang-tools-extra/unittests/include/common/VirtualFileHelper.h

   1 //===--- VirtualFileHelper.h ------------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 ///
   9 /// This file defines an utility class for tests that needs a source
  10 /// manager for a virtual file with customizable content.
  11 ///
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef CLANG_MODERNIZE_VIRTUAL_FILE_HELPER_H
  15 #define CLANG_MODERNIZE_VIRTUAL_FILE_HELPER_H
  16
  17 #include "clang/Basic/Diagnostic.h"
  18 #include "clang/Basic/DiagnosticOptions.h"
  19 #include "clang/Basic/FileManager.h"
  20 #include "clang/Basic/SourceManager.h"
  21 #include "clang/Frontend/TextDiagnosticPrinter.h"
  22
  23 namespace clang {
  24
  25 /// Class that provides easy access to a SourceManager and that allows to
  26 /// map virtual files conveniently.
  27 class VirtualFileHelper {
  28   struct VirtualFile {
  29     std::string FileName;
  30     std::string Code;
  31   };
  32
  33 public:
  34   VirtualFileHelper()
  35       : DiagOpts(new DiagnosticOptions()),
  36         Diagnostics(IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs),
  37                     &*DiagOpts),
  38         DiagnosticPrinter(llvm::outs(), &*DiagOpts),
  39         Files((FileSystemOptions())) {}
  40
  41   /// Create a virtual file \p FileName, with content \p Code.
  42   void mapFile(llvm::StringRef FileName, llvm::StringRef Code) {
  43     VirtualFile VF = { FileName, Code };
  44     VirtualFiles.push_back(VF);
  45   }
  46
  47   /// Create a new \c SourceManager with the virtual files and contents
  48   /// mapped to it.
  49   SourceManager &getNewSourceManager() {
  50     Sources.reset(new SourceManager(Diagnostics, Files));
  51     mapVirtualFiles(*Sources);
  52     return *Sources;
  53   }
  54
  55   /// Map the virtual file contents in the given \c SourceManager.
  56   void mapVirtualFiles(SourceManager &SM) const {
  57     for (llvm::SmallVectorImpl<VirtualFile>::const_iterator
  58              I = VirtualFiles.begin(),
  59              E = VirtualFiles.end();
  60          I != E; ++I) {
  61       std::unique_ptr<llvm::MemoryBuffer> Buf =
  62           llvm::MemoryBuffer::getMemBuffer(I->Code);
  63       const FileEntry *Entry = SM.getFileManager().getVirtualFile(
  64           I->FileName, Buf->getBufferSize(), /*ModificationTime=*/0);
  65       SM.overrideFileContents(Entry, std::move(Buf));
  66     }
  67   }
  68
  69 private:
  70   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts;
  71   DiagnosticsEngine Diagnostics;
  72   TextDiagnosticPrinter DiagnosticPrinter;
  73   FileManager Files;
  74   // most tests don't need more than one file
  75   llvm::SmallVector<VirtualFile, 1> VirtualFiles;
  76   std::unique_ptr<SourceManager> Sources;
  77 };
  78
  79 } // end namespace clang
  80
  81 #endif // CLANG_MODERNIZE_VIRTUAL_FILE_HELPER_H