1//===--- Refactoring.cpp - Framework for clang refactoring tools ----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  Implements tools to support refactorings.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Basic/DiagnosticOptions.h"
15#include "clang/Basic/FileManager.h"
16#include "clang/Basic/SourceManager.h"
17#include "clang/Frontend/TextDiagnosticPrinter.h"
18#include "clang/Lex/Lexer.h"
19#include "clang/Rewrite/Core/Rewriter.h"
20#include "clang/Tooling/Refactoring.h"
21#include "llvm/Support/raw_os_ostream.h"
22
23namespace clang {
24namespace tooling {
25
26static const char * const InvalidLocation = "";
27
28Replacement::Replacement()
29  : FilePath(InvalidLocation) {}
30
31Replacement::Replacement(StringRef FilePath, unsigned Offset, unsigned Length,
32                         StringRef ReplacementText)
33    : FilePath(FilePath), ReplacementRange(Offset, Length),
34      ReplacementText(ReplacementText) {}
35
36Replacement::Replacement(SourceManager &Sources, SourceLocation Start,
37                         unsigned Length, StringRef ReplacementText) {
38  setFromSourceLocation(Sources, Start, Length, ReplacementText);
39}
40
41Replacement::Replacement(SourceManager &Sources, const CharSourceRange &Range,
42                         StringRef ReplacementText) {
43  setFromSourceRange(Sources, Range, ReplacementText);
44}
45
46bool Replacement::isApplicable() const {
47  return FilePath != InvalidLocation;
48}
49
50bool Replacement::apply(Rewriter &Rewrite) const {
51  SourceManager &SM = Rewrite.getSourceMgr();
52  const FileEntry *Entry = SM.getFileManager().getFile(FilePath);
53  if (Entry == NULL)
54    return false;
55  FileID ID;
56  // FIXME: Use SM.translateFile directly.
57  SourceLocation Location = SM.translateFileLineCol(Entry, 1, 1);
58  ID = Location.isValid() ?
59    SM.getFileID(Location) :
60    SM.createFileID(Entry, SourceLocation(), SrcMgr::C_User);
61  // FIXME: We cannot check whether Offset + Length is in the file, as
62  // the remapping API is not public in the RewriteBuffer.
63  const SourceLocation Start =
64    SM.getLocForStartOfFile(ID).
65    getLocWithOffset(ReplacementRange.getOffset());
66  // ReplaceText returns false on success.
67  // ReplaceText only fails if the source location is not a file location, in
68  // which case we already returned false earlier.
69  bool RewriteSucceeded = !Rewrite.ReplaceText(
70      Start, ReplacementRange.getLength(), ReplacementText);
71  assert(RewriteSucceeded);
72  return RewriteSucceeded;
73}
74
75std::string Replacement::toString() const {
76  std::string result;
77  llvm::raw_string_ostream stream(result);
78  stream << FilePath << ": " << ReplacementRange.getOffset() << ":+"
79         << ReplacementRange.getLength() << ":\"" << ReplacementText << "\"";
80  return result;
81}
82
83bool Replacement::Less::operator()(const Replacement &R1,
84                                   const Replacement &R2) const {
85  if (R1.FilePath != R2.FilePath) return R1.FilePath < R2.FilePath;
86  if (R1.ReplacementRange.getOffset() != R2.ReplacementRange.getOffset())
87    return R1.ReplacementRange.getOffset() < R2.ReplacementRange.getOffset();
88  if (R1.ReplacementRange.getLength() != R2.ReplacementRange.getLength())
89    return R1.ReplacementRange.getLength() < R2.ReplacementRange.getLength();
90  return R1.ReplacementText < R2.ReplacementText;
91}
92
93void Replacement::setFromSourceLocation(SourceManager &Sources,
94                                        SourceLocation Start, unsigned Length,
95                                        StringRef ReplacementText) {
96  const std::pair<FileID, unsigned> DecomposedLocation =
97      Sources.getDecomposedLoc(Start);
98  const FileEntry *Entry = Sources.getFileEntryForID(DecomposedLocation.first);
99  this->FilePath = Entry != NULL ? Entry->getName() : InvalidLocation;
100  this->ReplacementRange = Range(DecomposedLocation.second, Length);
101  this->ReplacementText = ReplacementText;
102}
103
104// FIXME: This should go into the Lexer, but we need to figure out how
105// to handle ranges for refactoring in general first - there is no obvious
106// good way how to integrate this into the Lexer yet.
107static int getRangeSize(SourceManager &Sources, const CharSourceRange &Range) {
108  SourceLocation SpellingBegin = Sources.getSpellingLoc(Range.getBegin());
109  SourceLocation SpellingEnd = Sources.getSpellingLoc(Range.getEnd());
110  std::pair<FileID, unsigned> Start = Sources.getDecomposedLoc(SpellingBegin);
111  std::pair<FileID, unsigned> End = Sources.getDecomposedLoc(SpellingEnd);
112  if (Start.first != End.first) return -1;
113  if (Range.isTokenRange())
114    End.second += Lexer::MeasureTokenLength(SpellingEnd, Sources,
115                                            LangOptions());
116  return End.second - Start.second;
117}
118
119void Replacement::setFromSourceRange(SourceManager &Sources,
120                                     const CharSourceRange &Range,
121                                     StringRef ReplacementText) {
122  setFromSourceLocation(Sources, Sources.getSpellingLoc(Range.getBegin()),
123                        getRangeSize(Sources, Range), ReplacementText);
124}
125
126bool applyAllReplacements(const Replacements &Replaces, Rewriter &Rewrite) {
127  bool Result = true;
128  for (Replacements::const_iterator I = Replaces.begin(),
129                                    E = Replaces.end();
130       I != E; ++I) {
131    if (I->isApplicable()) {
132      Result = I->apply(Rewrite) && Result;
133    } else {
134      Result = false;
135    }
136  }
137  return Result;
138}
139
140std::string applyAllReplacements(StringRef Code, const Replacements &Replaces) {
141  FileManager Files((FileSystemOptions()));
142  DiagnosticsEngine Diagnostics(
143      IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs),
144      new DiagnosticOptions);
145  Diagnostics.setClient(new TextDiagnosticPrinter(
146      llvm::outs(), &Diagnostics.getDiagnosticOptions()));
147  SourceManager SourceMgr(Diagnostics, Files);
148  Rewriter Rewrite(SourceMgr, LangOptions());
149  llvm::MemoryBuffer *Buf = llvm::MemoryBuffer::getMemBuffer(Code, "<stdin>");
150  const clang::FileEntry *Entry =
151      Files.getVirtualFile("<stdin>", Buf->getBufferSize(), 0);
152  SourceMgr.overrideFileContents(Entry, Buf);
153  FileID ID =
154      SourceMgr.createFileID(Entry, SourceLocation(), clang::SrcMgr::C_User);
155  for (Replacements::const_iterator I = Replaces.begin(), E = Replaces.end();
156       I != E; ++I) {
157    Replacement Replace("<stdin>", I->getOffset(), I->getLength(),
158                        I->getReplacementText());
159    if (!Replace.apply(Rewrite))
160      return "";
161  }
162  std::string Result;
163  llvm::raw_string_ostream OS(Result);
164  Rewrite.getEditBuffer(ID).write(OS);
165  OS.flush();
166  return Result;
167}
168
169unsigned shiftedCodePosition(const Replacements &Replaces, unsigned Position) {
170  unsigned NewPosition = Position;
171  for (Replacements::iterator I = Replaces.begin(), E = Replaces.end(); I != E;
172       ++I) {
173    if (I->getOffset() >= Position)
174      break;
175    if (I->getOffset() + I->getLength() > Position)
176      NewPosition += I->getOffset() + I->getLength() - Position;
177    NewPosition += I->getReplacementText().size() - I->getLength();
178  }
179  return NewPosition;
180}
181
182RefactoringTool::RefactoringTool(const CompilationDatabase &Compilations,
183                                 ArrayRef<std::string> SourcePaths)
184  : ClangTool(Compilations, SourcePaths) {}
185
186Replacements &RefactoringTool::getReplacements() { return Replace; }
187
188int RefactoringTool::runAndSave(FrontendActionFactory *ActionFactory) {
189  if (int Result = run(ActionFactory)) {
190    return Result;
191  }
192
193  LangOptions DefaultLangOptions;
194  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
195  TextDiagnosticPrinter DiagnosticPrinter(llvm::errs(), &*DiagOpts);
196  DiagnosticsEngine Diagnostics(
197      IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs()),
198      &*DiagOpts, &DiagnosticPrinter, false);
199  SourceManager Sources(Diagnostics, getFiles());
200  Rewriter Rewrite(Sources, DefaultLangOptions);
201
202  if (!applyAllReplacements(Rewrite)) {
203    llvm::errs() << "Skipped some replacements.\n";
204  }
205
206  return saveRewrittenFiles(Rewrite);
207}
208
209bool RefactoringTool::applyAllReplacements(Rewriter &Rewrite) {
210  return tooling::applyAllReplacements(Replace, Rewrite);
211}
212
213int RefactoringTool::saveRewrittenFiles(Rewriter &Rewrite) {
214  for (Rewriter::buffer_iterator I = Rewrite.buffer_begin(),
215                                 E = Rewrite.buffer_end();
216       I != E; ++I) {
217    // FIXME: This code is copied from the FixItRewriter.cpp - I think it should
218    // go into directly into Rewriter (there we also have the Diagnostics to
219    // handle the error cases better).
220    const FileEntry *Entry =
221        Rewrite.getSourceMgr().getFileEntryForID(I->first);
222    std::string ErrorInfo;
223    llvm::raw_fd_ostream FileStream(Entry->getName(), ErrorInfo,
224                                    llvm::sys::fs::F_Binary);
225    if (!ErrorInfo.empty())
226      return 1;
227    I->second.write(FileStream);
228    FileStream.flush();
229  }
230  return 0;
231}
232
233} // end namespace tooling
234} // end namespace clang
235