1 //===--- ClangRefactor.cpp - Clang-based refactoring tool -----------------===//
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 /// \file
11 /// This file implements a clang-refactor tool that performs various
12 /// source transformations.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "TestSupport.h"
17 #include "clang/Frontend/CommandLineSourceLoc.h"
18 #include "clang/Frontend/TextDiagnosticPrinter.h"
19 #include "clang/Rewrite/Core/Rewriter.h"
20 #include "clang/Tooling/CommonOptionsParser.h"
21 #include "clang/Tooling/Refactoring.h"
22 #include "clang/Tooling/Refactoring/RefactoringAction.h"
23 #include "clang/Tooling/Refactoring/RefactoringOptions.h"
24 #include "clang/Tooling/Refactoring/Rename/RenamingAction.h"
25 #include "clang/Tooling/Tooling.h"
26 #include "llvm/Support/CommandLine.h"
27 #include "llvm/Support/FileSystem.h"
28 #include "llvm/Support/Signals.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <string>
31 
32 using namespace clang;
33 using namespace tooling;
34 using namespace refactor;
35 namespace cl = llvm::cl;
36 
37 namespace opts {
38 
39 static cl::OptionCategory CommonRefactorOptions("Refactoring options");
40 
41 static cl::opt<bool> Verbose("v", cl::desc("Use verbose output"),
42                              cl::cat(cl::GeneralCategory),
43                              cl::sub(*cl::AllSubCommands));
44 
45 static cl::opt<bool> Inplace("i", cl::desc("Inplace edit <file>s"),
46                              cl::cat(cl::GeneralCategory),
47                              cl::sub(*cl::AllSubCommands));
48 
49 } // end namespace opts
50 
51 namespace {
52 
53 /// Stores the parsed `-selection` argument.
54 class SourceSelectionArgument {
55 public:
56   virtual ~SourceSelectionArgument() {}
57 
58   /// Parse the `-selection` argument.
59   ///
60   /// \returns A valid argument when the parse succedeed, null otherwise.
61   static std::unique_ptr<SourceSelectionArgument> fromString(StringRef Value);
62 
63   /// Prints any additional state associated with the selection argument to
64   /// the given output stream.
65   virtual void print(raw_ostream &OS) {}
66 
67   /// Returns a replacement refactoring result consumer (if any) that should
68   /// consume the results of a refactoring operation.
69   ///
70   /// The replacement refactoring result consumer is used by \c
71   /// TestSourceSelectionArgument to inject a test-specific result handling
72   /// logic into the refactoring operation. The test-specific consumer
73   /// ensures that the individual results in a particular test group are
74   /// identical.
75   virtual std::unique_ptr<ClangRefactorToolConsumerInterface>
76   createCustomConsumer() {
77     return nullptr;
78   }
79 
80   /// Runs the give refactoring function for each specified selection.
81   ///
82   /// \returns true if an error occurred, false otherwise.
83   virtual bool
84   forAllRanges(const SourceManager &SM,
85                llvm::function_ref<void(SourceRange R)> Callback) = 0;
86 };
87 
88 /// Stores the parsed -selection=test:<filename> option.
89 class TestSourceSelectionArgument final : public SourceSelectionArgument {
90 public:
91   TestSourceSelectionArgument(TestSelectionRangesInFile TestSelections)
92       : TestSelections(std::move(TestSelections)) {}
93 
94   void print(raw_ostream &OS) override { TestSelections.dump(OS); }
95 
96   std::unique_ptr<ClangRefactorToolConsumerInterface>
97   createCustomConsumer() override {
98     return TestSelections.createConsumer();
99   }
100 
101   /// Testing support: invokes the selection action for each selection range in
102   /// the test file.
103   bool forAllRanges(const SourceManager &SM,
104                     llvm::function_ref<void(SourceRange R)> Callback) override {
105     return TestSelections.foreachRange(SM, Callback);
106   }
107 
108 private:
109   TestSelectionRangesInFile TestSelections;
110 };
111 
112 /// Stores the parsed -selection=filename:line:column[-line:column] option.
113 class SourceRangeSelectionArgument final : public SourceSelectionArgument {
114 public:
115   SourceRangeSelectionArgument(ParsedSourceRange Range)
116       : Range(std::move(Range)) {}
117 
118   bool forAllRanges(const SourceManager &SM,
119                     llvm::function_ref<void(SourceRange R)> Callback) override {
120     const FileEntry *FE = SM.getFileManager().getFile(Range.FileName);
121     FileID FID = FE ? SM.translateFile(FE) : FileID();
122     if (!FE || FID.isInvalid()) {
123       llvm::errs() << "error: -selection=" << Range.FileName
124                    << ":... : given file is not in the target TU\n";
125       return true;
126     }
127 
128     SourceLocation Start = SM.getMacroArgExpandedLocation(
129         SM.translateLineCol(FID, Range.Begin.first, Range.Begin.second));
130     SourceLocation End = SM.getMacroArgExpandedLocation(
131         SM.translateLineCol(FID, Range.End.first, Range.End.second));
132     if (Start.isInvalid() || End.isInvalid()) {
133       llvm::errs() << "error: -selection=" << Range.FileName << ':'
134                    << Range.Begin.first << ':' << Range.Begin.second << '-'
135                    << Range.End.first << ':' << Range.End.second
136                    << " : invalid source location\n";
137       return true;
138     }
139     Callback(SourceRange(Start, End));
140     return false;
141   }
142 
143 private:
144   ParsedSourceRange Range;
145 };
146 
147 std::unique_ptr<SourceSelectionArgument>
148 SourceSelectionArgument::fromString(StringRef Value) {
149   if (Value.startswith("test:")) {
150     StringRef Filename = Value.drop_front(strlen("test:"));
151     Optional<TestSelectionRangesInFile> ParsedTestSelection =
152         findTestSelectionRanges(Filename);
153     if (!ParsedTestSelection)
154       return nullptr; // A parsing error was already reported.
155     return llvm::make_unique<TestSourceSelectionArgument>(
156         std::move(*ParsedTestSelection));
157   }
158   Optional<ParsedSourceRange> Range = ParsedSourceRange::fromString(Value);
159   if (Range)
160     return llvm::make_unique<SourceRangeSelectionArgument>(std::move(*Range));
161   llvm::errs() << "error: '-selection' option must be specified using "
162                   "<file>:<line>:<column> or "
163                   "<file>:<line>:<column>-<line>:<column> format\n";
164   return nullptr;
165 }
166 
167 /// A container that stores the command-line options used by a single
168 /// refactoring option.
169 class RefactoringActionCommandLineOptions {
170 public:
171   void addStringOption(const RefactoringOption &Option,
172                        std::unique_ptr<cl::opt<std::string>> CLOption) {
173     StringOptions[&Option] = std::move(CLOption);
174   }
175 
176   const cl::opt<std::string> &
177   getStringOption(const RefactoringOption &Opt) const {
178     auto It = StringOptions.find(&Opt);
179     return *It->second;
180   }
181 
182 private:
183   llvm::DenseMap<const RefactoringOption *,
184                  std::unique_ptr<cl::opt<std::string>>>
185       StringOptions;
186 };
187 
188 /// Passes the command-line option values to the options used by a single
189 /// refactoring action rule.
190 class CommandLineRefactoringOptionVisitor final
191     : public RefactoringOptionVisitor {
192 public:
193   CommandLineRefactoringOptionVisitor(
194       const RefactoringActionCommandLineOptions &Options)
195       : Options(Options) {}
196 
197   void visit(const RefactoringOption &Opt,
198              Optional<std::string> &Value) override {
199     const cl::opt<std::string> &CLOpt = Options.getStringOption(Opt);
200     if (!CLOpt.getValue().empty()) {
201       Value = CLOpt.getValue();
202       return;
203     }
204     Value = None;
205     if (Opt.isRequired())
206       MissingRequiredOptions.push_back(&Opt);
207   }
208 
209   ArrayRef<const RefactoringOption *> getMissingRequiredOptions() const {
210     return MissingRequiredOptions;
211   }
212 
213 private:
214   llvm::SmallVector<const RefactoringOption *, 4> MissingRequiredOptions;
215   const RefactoringActionCommandLineOptions &Options;
216 };
217 
218 /// Creates the refactoring options used by all the rules in a single
219 /// refactoring action.
220 class CommandLineRefactoringOptionCreator final
221     : public RefactoringOptionVisitor {
222 public:
223   CommandLineRefactoringOptionCreator(
224       cl::OptionCategory &Category, cl::SubCommand &Subcommand,
225       RefactoringActionCommandLineOptions &Options)
226       : Category(Category), Subcommand(Subcommand), Options(Options) {}
227 
228   void visit(const RefactoringOption &Opt, Optional<std::string> &) override {
229     if (Visited.insert(&Opt).second)
230       Options.addStringOption(Opt, create<std::string>(Opt));
231   }
232 
233 private:
234   template <typename T>
235   std::unique_ptr<cl::opt<T>> create(const RefactoringOption &Opt) {
236     if (!OptionNames.insert(Opt.getName()).second)
237       llvm::report_fatal_error("Multiple identical refactoring options "
238                                "specified for one refactoring action");
239     // FIXME: cl::Required can be specified when this option is present
240     // in all rules in an action.
241     return llvm::make_unique<cl::opt<T>>(
242         Opt.getName(), cl::desc(Opt.getDescription()), cl::Optional,
243         cl::cat(Category), cl::sub(Subcommand));
244   }
245 
246   llvm::SmallPtrSet<const RefactoringOption *, 8> Visited;
247   llvm::StringSet<> OptionNames;
248   cl::OptionCategory &Category;
249   cl::SubCommand &Subcommand;
250   RefactoringActionCommandLineOptions &Options;
251 };
252 
253 /// A subcommand that corresponds to individual refactoring action.
254 class RefactoringActionSubcommand : public cl::SubCommand {
255 public:
256   RefactoringActionSubcommand(std::unique_ptr<RefactoringAction> Action,
257                               RefactoringActionRules ActionRules,
258                               cl::OptionCategory &Category)
259       : SubCommand(Action->getCommand(), Action->getDescription()),
260         Action(std::move(Action)), ActionRules(std::move(ActionRules)) {
261     // Check if the selection option is supported.
262     for (const auto &Rule : this->ActionRules) {
263       if (Rule->hasSelectionRequirement()) {
264         Selection = llvm::make_unique<cl::opt<std::string>>(
265             "selection",
266             cl::desc(
267                 "The selected source range in which the refactoring should "
268                 "be initiated (<file>:<line>:<column>-<line>:<column> or "
269                 "<file>:<line>:<column>)"),
270             cl::cat(Category), cl::sub(*this));
271         break;
272       }
273     }
274     // Create the refactoring options.
275     for (const auto &Rule : this->ActionRules) {
276       CommandLineRefactoringOptionCreator OptionCreator(Category, *this,
277                                                         Options);
278       Rule->visitRefactoringOptions(OptionCreator);
279     }
280   }
281 
282   ~RefactoringActionSubcommand() { unregisterSubCommand(); }
283 
284   const RefactoringActionRules &getActionRules() const { return ActionRules; }
285 
286   /// Parses the "-selection" command-line argument.
287   ///
288   /// \returns true on error, false otherwise.
289   bool parseSelectionArgument() {
290     if (Selection) {
291       ParsedSelection = SourceSelectionArgument::fromString(*Selection);
292       if (!ParsedSelection)
293         return true;
294     }
295     return false;
296   }
297 
298   SourceSelectionArgument *getSelection() const {
299     assert(Selection && "selection not supported!");
300     return ParsedSelection.get();
301   }
302 
303   const RefactoringActionCommandLineOptions &getOptions() const {
304     return Options;
305   }
306 
307 private:
308   std::unique_ptr<RefactoringAction> Action;
309   RefactoringActionRules ActionRules;
310   std::unique_ptr<cl::opt<std::string>> Selection;
311   std::unique_ptr<SourceSelectionArgument> ParsedSelection;
312   RefactoringActionCommandLineOptions Options;
313 };
314 
315 class ClangRefactorConsumer final : public ClangRefactorToolConsumerInterface {
316 public:
317   ClangRefactorConsumer(AtomicChanges &Changes) : SourceChanges(&Changes) {}
318 
319   void handleError(llvm::Error Err) override {
320     Optional<PartialDiagnosticAt> Diag = DiagnosticError::take(Err);
321     if (!Diag) {
322       llvm::errs() << llvm::toString(std::move(Err)) << "\n";
323       return;
324     }
325     llvm::cantFail(std::move(Err)); // This is a success.
326     DiagnosticBuilder DB(
327         getDiags().Report(Diag->first, Diag->second.getDiagID()));
328     Diag->second.Emit(DB);
329   }
330 
331   void handle(AtomicChanges Changes) override {
332     SourceChanges->insert(SourceChanges->begin(), Changes.begin(),
333                           Changes.end());
334   }
335 
336   void handle(SymbolOccurrences Occurrences) override {
337     llvm_unreachable("symbol occurrence results are not handled yet");
338   }
339 
340 private:
341   AtomicChanges *SourceChanges;
342 };
343 
344 class ClangRefactorTool {
345 public:
346   ClangRefactorTool()
347       : SelectedSubcommand(nullptr), MatchingRule(nullptr),
348         Consumer(new ClangRefactorConsumer(Changes)), HasFailed(false) {
349     std::vector<std::unique_ptr<RefactoringAction>> Actions =
350         createRefactoringActions();
351 
352     // Actions must have unique command names so that we can map them to one
353     // subcommand.
354     llvm::StringSet<> CommandNames;
355     for (const auto &Action : Actions) {
356       if (!CommandNames.insert(Action->getCommand()).second) {
357         llvm::errs() << "duplicate refactoring action command '"
358                      << Action->getCommand() << "'!";
359         exit(1);
360       }
361     }
362 
363     // Create subcommands and command-line options.
364     for (auto &Action : Actions) {
365       SubCommands.push_back(llvm::make_unique<RefactoringActionSubcommand>(
366           std::move(Action), Action->createActiveActionRules(),
367           opts::CommonRefactorOptions));
368     }
369   }
370 
371   // Initializes the selected subcommand and refactoring rule based on the
372   // command line options.
373   llvm::Error Init() {
374     auto Subcommand = getSelectedSubcommand();
375     if (!Subcommand)
376       return Subcommand.takeError();
377     auto Rule = getMatchingRule(**Subcommand);
378     if (!Rule)
379       return Rule.takeError();
380 
381     SelectedSubcommand = *Subcommand;
382     MatchingRule = *Rule;
383 
384     return llvm::Error::success();
385   }
386 
387   bool hasFailed() const { return HasFailed; }
388 
389   using TUCallbackType = std::function<void(ASTContext &)>;
390 
391   // Callback of an AST action. This invokes the matching rule on the given AST.
392   void callback(ASTContext &AST) {
393     assert(SelectedSubcommand && MatchingRule && Consumer);
394     RefactoringRuleContext Context(AST.getSourceManager());
395     Context.setASTContext(AST);
396 
397     // If the selection option is test specific, we use a test-specific
398     // consumer.
399     std::unique_ptr<ClangRefactorToolConsumerInterface> TestConsumer;
400     bool HasSelection = MatchingRule->hasSelectionRequirement();
401     if (HasSelection)
402       TestConsumer = SelectedSubcommand->getSelection()->createCustomConsumer();
403     ClangRefactorToolConsumerInterface *ActiveConsumer =
404         TestConsumer ? TestConsumer.get() : Consumer.get();
405     ActiveConsumer->beginTU(AST);
406 
407     auto InvokeRule = [&](RefactoringResultConsumer &Consumer) {
408       if (opts::Verbose)
409         logInvocation(*SelectedSubcommand, Context);
410       MatchingRule->invoke(*ActiveConsumer, Context);
411     };
412     if (HasSelection) {
413       assert(SelectedSubcommand->getSelection() &&
414              "Missing selection argument?");
415       if (opts::Verbose)
416         SelectedSubcommand->getSelection()->print(llvm::outs());
417       if (SelectedSubcommand->getSelection()->forAllRanges(
418               Context.getSources(), [&](SourceRange R) {
419                 Context.setSelectionRange(R);
420                 InvokeRule(*ActiveConsumer);
421               }))
422         HasFailed = true;
423       ActiveConsumer->endTU();
424       return;
425     }
426     InvokeRule(*ActiveConsumer);
427     ActiveConsumer->endTU();
428   }
429 
430   llvm::Expected<std::unique_ptr<FrontendActionFactory>>
431   getFrontendActionFactory() {
432     class ToolASTConsumer : public ASTConsumer {
433     public:
434       TUCallbackType Callback;
435       ToolASTConsumer(TUCallbackType Callback)
436           : Callback(std::move(Callback)) {}
437 
438       void HandleTranslationUnit(ASTContext &Context) override {
439         Callback(Context);
440       }
441     };
442     class ToolASTAction : public ASTFrontendAction {
443     public:
444       explicit ToolASTAction(TUCallbackType Callback)
445           : Callback(std::move(Callback)) {}
446 
447     protected:
448       std::unique_ptr<clang::ASTConsumer>
449       CreateASTConsumer(clang::CompilerInstance &compiler,
450                         StringRef /* dummy */) override {
451         std::unique_ptr<clang::ASTConsumer> Consumer{
452             new ToolASTConsumer(Callback)};
453         return Consumer;
454       }
455 
456     private:
457       TUCallbackType Callback;
458     };
459 
460     class ToolActionFactory : public FrontendActionFactory {
461     public:
462       ToolActionFactory(TUCallbackType Callback)
463           : Callback(std::move(Callback)) {}
464 
465       FrontendAction *create() override { return new ToolASTAction(Callback); }
466 
467     private:
468       TUCallbackType Callback;
469     };
470 
471     return llvm::make_unique<ToolActionFactory>(
472         [this](ASTContext &AST) { return callback(AST); });
473   }
474 
475   // FIXME(ioeric): this seems to only works for changes in a single file at
476   // this point.
477   bool applySourceChanges() {
478     std::set<std::string> Files;
479     for (const auto &Change : Changes)
480       Files.insert(Change.getFilePath());
481     // FIXME: Add automatic formatting support as well.
482     tooling::ApplyChangesSpec Spec;
483     // FIXME: We should probably cleanup the result by default as well.
484     Spec.Cleanup = false;
485     for (const auto &File : Files) {
486       llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> BufferErr =
487           llvm::MemoryBuffer::getFile(File);
488       if (!BufferErr) {
489         llvm::errs() << "error: failed to open " << File << " for rewriting\n";
490         return true;
491       }
492       auto Result = tooling::applyAtomicChanges(File, (*BufferErr)->getBuffer(),
493                                                 Changes, Spec);
494       if (!Result) {
495         llvm::errs() << toString(Result.takeError());
496         return true;
497       }
498 
499       if (opts::Inplace) {
500         std::error_code EC;
501         llvm::raw_fd_ostream OS(File, EC, llvm::sys::fs::F_Text);
502         if (EC) {
503           llvm::errs() << EC.message() << "\n";
504           return true;
505         }
506         OS << *Result;
507         continue;
508       }
509 
510       llvm::outs() << *Result;
511     }
512     return false;
513   }
514 
515 private:
516   /// Logs an individual refactoring action invocation to STDOUT.
517   void logInvocation(RefactoringActionSubcommand &Subcommand,
518                      const RefactoringRuleContext &Context) {
519     llvm::outs() << "invoking action '" << Subcommand.getName() << "':\n";
520     if (Context.getSelectionRange().isValid()) {
521       SourceRange R = Context.getSelectionRange();
522       llvm::outs() << "  -selection=";
523       R.getBegin().print(llvm::outs(), Context.getSources());
524       llvm::outs() << " -> ";
525       R.getEnd().print(llvm::outs(), Context.getSources());
526       llvm::outs() << "\n";
527     }
528   }
529 
530   llvm::Expected<RefactoringActionRule *>
531   getMatchingRule(RefactoringActionSubcommand &Subcommand) {
532     SmallVector<RefactoringActionRule *, 4> MatchingRules;
533     llvm::StringSet<> MissingOptions;
534 
535     for (const auto &Rule : Subcommand.getActionRules()) {
536       CommandLineRefactoringOptionVisitor Visitor(Subcommand.getOptions());
537       Rule->visitRefactoringOptions(Visitor);
538       if (Visitor.getMissingRequiredOptions().empty()) {
539         if (!Rule->hasSelectionRequirement()) {
540           MatchingRules.push_back(Rule.get());
541         } else {
542           Subcommand.parseSelectionArgument();
543           if (Subcommand.getSelection()) {
544             MatchingRules.push_back(Rule.get());
545           } else {
546             MissingOptions.insert("selection");
547           }
548         }
549       }
550       for (const RefactoringOption *Opt : Visitor.getMissingRequiredOptions())
551         MissingOptions.insert(Opt->getName());
552     }
553     if (MatchingRules.empty()) {
554       std::string Error;
555       llvm::raw_string_ostream OS(Error);
556       OS << "ERROR: '" << Subcommand.getName()
557          << "' can't be invoked with the given arguments:\n";
558       for (const auto &Opt : MissingOptions)
559         OS << "  missing '-" << Opt.getKey() << "' option\n";
560       OS.flush();
561       return llvm::make_error<llvm::StringError>(
562           Error, llvm::inconvertibleErrorCode());
563     }
564     if (MatchingRules.size() != 1) {
565       return llvm::make_error<llvm::StringError>(
566           llvm::Twine("ERROR: more than one matching rule of action") +
567               Subcommand.getName() + "was found with given options.",
568           llvm::inconvertibleErrorCode());
569     }
570     return MatchingRules.front();
571   }
572   // Figure out which action is specified by the user. The user must specify the
573   // action using a command-line subcommand, e.g. the invocation `clang-refactor
574   // local-rename` corresponds to the `LocalRename` refactoring action. All
575   // subcommands must have a unique names. This allows us to figure out which
576   // refactoring action should be invoked by looking at the first subcommand
577   // that's enabled by LLVM's command-line parser.
578   llvm::Expected<RefactoringActionSubcommand *> getSelectedSubcommand() {
579     auto It = llvm::find_if(
580         SubCommands,
581         [](const std::unique_ptr<RefactoringActionSubcommand> &SubCommand) {
582           return !!(*SubCommand);
583         });
584     if (It == SubCommands.end()) {
585       std::string Error;
586       llvm::raw_string_ostream OS(Error);
587       OS << "error: no refactoring action given\n";
588       OS << "note: the following actions are supported:\n";
589       for (const auto &Subcommand : SubCommands)
590         OS.indent(2) << Subcommand->getName() << "\n";
591       OS.flush();
592       return llvm::make_error<llvm::StringError>(
593           Error, llvm::inconvertibleErrorCode());
594     }
595     RefactoringActionSubcommand *Subcommand = &(**It);
596     return Subcommand;
597   }
598 
599   std::vector<std::unique_ptr<RefactoringActionSubcommand>> SubCommands;
600   RefactoringActionSubcommand *SelectedSubcommand;
601   RefactoringActionRule *MatchingRule;
602   std::unique_ptr<ClangRefactorToolConsumerInterface> Consumer;
603   AtomicChanges Changes;
604   bool HasFailed;
605 };
606 
607 } // end anonymous namespace
608 
609 int main(int argc, const char **argv) {
610   llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
611 
612   ClangRefactorTool RefactorTool;
613 
614   CommonOptionsParser Options(
615       argc, argv, cl::GeneralCategory, cl::ZeroOrMore,
616       "Clang-based refactoring tool for C, C++ and Objective-C");
617 
618   if (auto Err = RefactorTool.Init()) {
619     llvm::errs() << llvm::toString(std::move(Err)) << "\n";
620     return 1;
621   }
622 
623   auto ActionFactory = RefactorTool.getFrontendActionFactory();
624   if (!ActionFactory) {
625     llvm::errs() << llvm::toString(ActionFactory.takeError()) << "\n";
626     return 1;
627   }
628   ClangTool Tool(Options.getCompilations(), Options.getSourcePathList());
629   bool Failed = false;
630   if (Tool.run(ActionFactory->get()) != 0) {
631     llvm::errs() << "Failed to run refactoring action on files\n";
632     // It is possible that TUs are broken while changes are generated correctly,
633     // so we still try applying changes.
634     Failed = true;
635   }
636   return RefactorTool.applySourceChanges() || Failed ||
637          RefactorTool.hasFailed();
638 }
639