clang  10.0.0svn
FixItRewriter.cpp
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1 //===- FixItRewriter.cpp - Fix-It Rewriter Diagnostic Client --------------===//
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 is a diagnostic client adaptor that performs rewrites as
10 // suggested by code modification hints attached to diagnostics. It
11 // then forwards any diagnostics to the adapted diagnostic client.
12 //
13 //===----------------------------------------------------------------------===//
14 
16 #include "clang/Basic/Diagnostic.h"
18 #include "clang/Basic/LLVM.h"
21 #include "clang/Edit/Commit.h"
26 #include "llvm/ADT/StringRef.h"
27 #include "llvm/Support/FileSystem.h"
28 #include "llvm/Support/raw_ostream.h"
29 #include <cstdio>
30 #include <memory>
31 #include <string>
32 #include <system_error>
33 #include <utility>
34 
35 using namespace clang;
36 
38  const LangOptions &LangOpts,
39  FixItOptions *FixItOpts)
40  : Diags(Diags), Editor(SourceMgr, LangOpts), Rewrite(SourceMgr, LangOpts),
41  FixItOpts(FixItOpts) {
42  Owner = Diags.takeClient();
43  Client = Diags.getClient();
44  Diags.setClient(this, false);
45 }
46 
48  Diags.setClient(Client, Owner.release() != nullptr);
49 }
50 
51 bool FixItRewriter::WriteFixedFile(FileID ID, raw_ostream &OS) {
52  const RewriteBuffer *RewriteBuf = Rewrite.getRewriteBufferFor(ID);
53  if (!RewriteBuf) return true;
54  RewriteBuf->write(OS);
55  OS.flush();
56  return false;
57 }
58 
59 namespace {
60 
61 class RewritesReceiver : public edit::EditsReceiver {
62  Rewriter &Rewrite;
63 
64 public:
65  RewritesReceiver(Rewriter &Rewrite) : Rewrite(Rewrite) {}
66 
67  void insert(SourceLocation loc, StringRef text) override {
68  Rewrite.InsertText(loc, text);
69  }
70 
71  void replace(CharSourceRange range, StringRef text) override {
72  Rewrite.ReplaceText(range.getBegin(), Rewrite.getRangeSize(range), text);
73  }
74 };
75 
76 } // namespace
77 
79  std::vector<std::pair<std::string, std::string>> *RewrittenFiles) {
80  if (NumFailures > 0 && !FixItOpts->FixWhatYouCan) {
81  Diag(FullSourceLoc(), diag::warn_fixit_no_changes);
82  return true;
83  }
84 
85  RewritesReceiver Rec(Rewrite);
86  Editor.applyRewrites(Rec);
87 
88  if (FixItOpts->InPlace) {
89  // Overwriting open files on Windows is tricky, but the rewriter can do it
90  // for us.
91  Rewrite.overwriteChangedFiles();
92  return false;
93  }
94 
95  for (iterator I = buffer_begin(), E = buffer_end(); I != E; ++I) {
96  const FileEntry *Entry = Rewrite.getSourceMgr().getFileEntryForID(I->first);
97  int fd;
98  std::string Filename = FixItOpts->RewriteFilename(Entry->getName(), fd);
99  std::error_code EC;
100  std::unique_ptr<llvm::raw_fd_ostream> OS;
101  if (fd != -1) {
102  OS.reset(new llvm::raw_fd_ostream(fd, /*shouldClose=*/true));
103  } else {
104  OS.reset(new llvm::raw_fd_ostream(Filename, EC, llvm::sys::fs::OF_None));
105  }
106  if (EC) {
107  Diags.Report(clang::diag::err_fe_unable_to_open_output) << Filename
108  << EC.message();
109  continue;
110  }
111  RewriteBuffer &RewriteBuf = I->second;
112  RewriteBuf.write(*OS);
113  OS->flush();
114 
115  if (RewrittenFiles)
116  RewrittenFiles->push_back(std::make_pair(Entry->getName(), Filename));
117  }
118 
119  return false;
120 }
121 
123  return Client ? Client->IncludeInDiagnosticCounts() : true;
124 }
125 
127  const Diagnostic &Info) {
128  // Default implementation (Warnings/errors count).
129  DiagnosticConsumer::HandleDiagnostic(DiagLevel, Info);
130 
131  if (!FixItOpts->Silent ||
132  DiagLevel >= DiagnosticsEngine::Error ||
133  (DiagLevel == DiagnosticsEngine::Note && !PrevDiagSilenced) ||
134  (DiagLevel > DiagnosticsEngine::Note && Info.getNumFixItHints())) {
135  Client->HandleDiagnostic(DiagLevel, Info);
136  PrevDiagSilenced = false;
137  } else {
138  PrevDiagSilenced = true;
139  }
140 
141  // Skip over any diagnostics that are ignored or notes.
142  if (DiagLevel <= DiagnosticsEngine::Note)
143  return;
144  // Skip over errors if we are only fixing warnings.
145  if (DiagLevel >= DiagnosticsEngine::Error && FixItOpts->FixOnlyWarnings) {
146  ++NumFailures;
147  return;
148  }
149 
150  // Make sure that we can perform all of the modifications we
151  // in this diagnostic.
152  edit::Commit commit(Editor);
153  for (unsigned Idx = 0, Last = Info.getNumFixItHints();
154  Idx < Last; ++Idx) {
155  const FixItHint &Hint = Info.getFixItHint(Idx);
156 
157  if (Hint.CodeToInsert.empty()) {
158  if (Hint.InsertFromRange.isValid())
159  commit.insertFromRange(Hint.RemoveRange.getBegin(),
160  Hint.InsertFromRange, /*afterToken=*/false,
162  else
163  commit.remove(Hint.RemoveRange);
164  } else {
165  if (Hint.RemoveRange.isTokenRange() ||
166  Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())
167  commit.replace(Hint.RemoveRange, Hint.CodeToInsert);
168  else
169  commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,
170  /*afterToken=*/false, Hint.BeforePreviousInsertions);
171  }
172  }
173  bool CanRewrite = Info.getNumFixItHints() > 0 && commit.isCommitable();
174 
175  if (!CanRewrite) {
176  if (Info.getNumFixItHints() > 0)
177  Diag(Info.getLocation(), diag::note_fixit_in_macro);
178 
179  // If this was an error, refuse to perform any rewriting.
180  if (DiagLevel >= DiagnosticsEngine::Error) {
181  if (++NumFailures == 1)
182  Diag(Info.getLocation(), diag::note_fixit_unfixed_error);
183  }
184  return;
185  }
186 
187  if (!Editor.commit(commit)) {
188  ++NumFailures;
189  Diag(Info.getLocation(), diag::note_fixit_failed);
190  return;
191  }
192 
193  Diag(Info.getLocation(), diag::note_fixit_applied);
194 }
195 
196 /// Emit a diagnostic via the adapted diagnostic client.
197 void FixItRewriter::Diag(SourceLocation Loc, unsigned DiagID) {
198  // When producing this diagnostic, we temporarily bypass ourselves,
199  // clear out any current diagnostic, and let the downstream client
200  // format the diagnostic.
201  Diags.setClient(Client, false);
202  Diags.Clear();
203  Diags.Report(Loc, DiagID);
204  Diags.setClient(this, false);
205 }
206 
207 FixItOptions::~FixItOptions() = default;
bool remove(CharSourceRange range)
Definition: Commit.cpp:91
DiagnosticConsumer * getClient()
Definition: Diagnostic.h:510
Defines the clang::FileManager interface and associated types.
Defines the SourceManager interface.
std::string CodeToInsert
The actual code to insert at the insertion location, as a string.
Definition: Diagnostic.h:78
bool insertFromRange(SourceLocation loc, CharSourceRange range, bool afterToken=false, bool beforePreviousInsertions=false)
Definition: Commit.cpp:64
std::unique_ptr< DiagnosticConsumer > takeClient()
Return the current diagnostic client along with ownership of that client.
Definition: Diagnostic.h:518
RangeSelector range(RangeSelector Begin, RangeSelector End)
Selects from the start of Begin and to the end of End.
RewriteBuffer - As code is rewritten, SourceBuffer&#39;s from the original input with modifications get a...
Definition: RewriteBuffer.h:25
bool WriteFixedFiles(std::vector< std::pair< std::string, std::string >> *RewrittenFiles=nullptr)
Write the modified source files.
bool insert(SourceLocation loc, StringRef text, bool afterToken=false, bool beforePreviousInsertions=false)
Definition: Commit.cpp:48
void setClient(DiagnosticConsumer *client, bool ShouldOwnClient=true)
Set the diagnostic client associated with this diagnostic object.
Definition: Diagnostic.cpp:99
SourceLocation getBegin() const
const FixItHint & getFixItHint(unsigned Idx) const
Definition: Diagnostic.h:1413
bool ReplaceText(SourceLocation Start, unsigned OrigLength, StringRef NewStr)
ReplaceText - This method replaces a range of characters in the input buffer with a new string...
Definition: Rewriter.cpp:320
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:49
bool replace(CharSourceRange range, StringRef text)
Definition: Commit.cpp:116
const SourceLocation & getLocation() const
Definition: Diagnostic.h:1328
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:149
~FixItRewriter() override
Destroy the fix-it rewriter.
Defines the Diagnostic-related interfaces.
StringRef Filename
Definition: Format.cpp:1807
Represents a character-granular source range.
bool BeforePreviousInsertions
Definition: Diagnostic.h:80
int getRangeSize(SourceRange Range, RewriteOptions opts=RewriteOptions()) const
getRangeSize - Return the size in bytes of the specified range if they are in the same file...
Definition: Rewriter.cpp:175
CharSourceRange InsertFromRange
Code in the specific range that should be inserted in the insertion location.
Definition: Diagnostic.h:74
bool WriteFixedFile(FileID ID, raw_ostream &OS)
Write a single modified source file.
CharSourceRange RemoveRange
Code that should be replaced to correct the error.
Definition: Diagnostic.h:70
FixItRewriter(DiagnosticsEngine &Diags, SourceManager &SourceMgr, const LangOptions &LangOpts, FixItOptions *FixItOpts)
Initialize a new fix-it rewriter.
Encodes a location in the source.
raw_ostream & write(raw_ostream &Stream) const
Write to Stream the result of applying all changes to the original buffer.
Definition: Rewriter.cpp:37
StringRef getName() const
Definition: FileManager.h:102
Cached information about one file (either on disk or in the virtual file system). ...
Definition: FileManager.h:78
const RewriteBuffer * getRewriteBufferFor(FileID FID) const
getRewriteBufferFor - Return the rewrite buffer for the specified FileID.
Definition: Rewriter.h:198
void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel, const Diagnostic &Info) override
HandleDiagnostic - Handle this diagnostic, reporting it to the user or capturing it to a log as neede...
bool InsertText(SourceLocation Loc, StringRef Str, bool InsertAfter=true, bool indentNewLines=false)
InsertText - Insert the specified string at the specified location in the original buffer...
Definition: Rewriter.cpp:255
virtual void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel, const Diagnostic &Info)
Handle this diagnostic, reporting it to the user or capturing it to a log as needed.
Definition: Diagnostic.cpp:531
bool isTokenRange() const
Return true if the end of this range specifies the start of the last token.
An opaque identifier used by SourceManager which refers to a source file (MemoryBuffer) along with it...
Dataflow Directional Tag Classes.
bool isCommitable() const
Definition: Commit.h:68
void Diag(SourceLocation Loc, unsigned DiagID)
Emit a diagnostic via the adapted diagnostic client.
unsigned getNumFixItHints() const
Definition: Diagnostic.h:1409
Rewriter::buffer_iterator iterator
SourceLocation getEnd() const
virtual ~FixItOptions()
Rewriter - This is the main interface to the rewrite buffers.
Definition: Rewriter.h:32
Defines the clang::SourceLocation class and associated facilities.
Level
The level of the diagnostic, after it has been through mapping.
Definition: Diagnostic.h:152
A little helper class (which is basically a smart pointer that forwards info from DiagnosticsEngine) ...
Definition: Diagnostic.h:1317
A SourceLocation and its associated SourceManager.
Annotates a diagnostic with some code that should be inserted, removed, or replaced to fix the proble...
Definition: Diagnostic.h:66
This class handles loading and caching of source files into memory.
bool IncludeInDiagnosticCounts() const override
IncludeInDiagnosticCounts - This method (whose default implementation returns true) indicates whether...