1 //===--- RenamingAction.cpp - Clang refactoring library -------------------===//
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 /// \file
10 /// Provides an action to rename every symbol at a point.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Tooling/Refactoring/Rename/RenamingAction.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/Basic/FileManager.h"
18 #include "clang/Frontend/CompilerInstance.h"
19 #include "clang/Frontend/FrontendAction.h"
20 #include "clang/Lex/Lexer.h"
21 #include "clang/Lex/Preprocessor.h"
22 #include "clang/Tooling/CommonOptionsParser.h"
23 #include "clang/Tooling/Refactoring.h"
24 #include "clang/Tooling/Refactoring/RefactoringAction.h"
25 #include "clang/Tooling/Refactoring/RefactoringDiagnostic.h"
26 #include "clang/Tooling/Refactoring/RefactoringOptions.h"
27 #include "clang/Tooling/Refactoring/Rename/SymbolName.h"
28 #include "clang/Tooling/Refactoring/Rename/USRFinder.h"
29 #include "clang/Tooling/Refactoring/Rename/USRFindingAction.h"
30 #include "clang/Tooling/Refactoring/Rename/USRLocFinder.h"
31 #include "clang/Tooling/Tooling.h"
32 #include "llvm/ADT/STLExtras.h"
33 #include "llvm/Support/Errc.h"
34 #include "llvm/Support/Error.h"
35 #include <string>
36 #include <vector>
37 
38 using namespace llvm;
39 
40 namespace clang {
41 namespace tooling {
42 
43 namespace {
44 
45 Expected<SymbolOccurrences>
46 findSymbolOccurrences(const NamedDecl *ND, RefactoringRuleContext &Context) {
47   std::vector<std::string> USRs =
48       getUSRsForDeclaration(ND, Context.getASTContext());
49   std::string PrevName = ND->getNameAsString();
50   return getOccurrencesOfUSRs(USRs, PrevName,
51                               Context.getASTContext().getTranslationUnitDecl());
52 }
53 
54 } // end anonymous namespace
55 
56 const RefactoringDescriptor &RenameOccurrences::describe() {
57   static const RefactoringDescriptor Descriptor = {
58       "local-rename",
59       "Rename",
60       "Finds and renames symbols in code with no indexer support",
61   };
62   return Descriptor;
63 }
64 
65 Expected<RenameOccurrences>
66 RenameOccurrences::initiate(RefactoringRuleContext &Context,
67                             SourceRange SelectionRange, std::string NewName) {
68   const NamedDecl *ND =
69       getNamedDeclAt(Context.getASTContext(), SelectionRange.getBegin());
70   if (!ND)
71     return Context.createDiagnosticError(
72         SelectionRange.getBegin(), diag::err_refactor_selection_no_symbol);
73   return RenameOccurrences(getCanonicalSymbolDeclaration(ND),
74                            std::move(NewName));
75 }
76 
77 Expected<AtomicChanges>
78 RenameOccurrences::createSourceReplacements(RefactoringRuleContext &Context) {
79   Expected<SymbolOccurrences> Occurrences = findSymbolOccurrences(ND, Context);
80   if (!Occurrences)
81     return Occurrences.takeError();
82   // FIXME: Verify that the new name is valid.
83   SymbolName Name(NewName);
84   return createRenameReplacements(
85       *Occurrences, Context.getASTContext().getSourceManager(), Name);
86 }
87 
88 Expected<QualifiedRenameRule>
89 QualifiedRenameRule::initiate(RefactoringRuleContext &Context,
90                               std::string OldQualifiedName,
91                               std::string NewQualifiedName) {
92   const NamedDecl *ND =
93       getNamedDeclFor(Context.getASTContext(), OldQualifiedName);
94   if (!ND)
95     return llvm::make_error<llvm::StringError>("Could not find symbol " +
96                                                    OldQualifiedName,
97                                                llvm::errc::invalid_argument);
98   return QualifiedRenameRule(ND, std::move(NewQualifiedName));
99 }
100 
101 const RefactoringDescriptor &QualifiedRenameRule::describe() {
102   static const RefactoringDescriptor Descriptor = {
103       /*Name=*/"local-qualified-rename",
104       /*Title=*/"Qualified Rename",
105       /*Description=*/
106       R"(Finds and renames qualified symbols in code within a translation unit.
107 It is used to move/rename a symbol to a new namespace/name:
108   * Supported symbols: classes, class members, functions, enums, and type alias.
109   * Renames all symbol occurrences from the old qualified name to the new
110     qualified name. All symbol references will be correctly qualified; For
111     symbol definitions, only name will be changed.
112 For example, rename "A::Foo" to "B::Bar":
113   Old code:
114     namespace foo {
115     class A {};
116     }
117 
118     namespace bar {
119     void f(foo::A a) {}
120     }
121 
122   New code after rename:
123     namespace foo {
124     class B {};
125     }
126 
127     namespace bar {
128     void f(B b) {}
129     })"
130   };
131   return Descriptor;
132 }
133 
134 Expected<AtomicChanges>
135 QualifiedRenameRule::createSourceReplacements(RefactoringRuleContext &Context) {
136   auto USRs = getUSRsForDeclaration(ND, Context.getASTContext());
137   assert(!USRs.empty());
138   return tooling::createRenameAtomicChanges(
139       USRs, NewQualifiedName, Context.getASTContext().getTranslationUnitDecl());
140 }
141 
142 Expected<std::vector<AtomicChange>>
143 createRenameReplacements(const SymbolOccurrences &Occurrences,
144                          const SourceManager &SM, const SymbolName &NewName) {
145   // FIXME: A true local rename can use just one AtomicChange.
146   std::vector<AtomicChange> Changes;
147   for (const auto &Occurrence : Occurrences) {
148     ArrayRef<SourceRange> Ranges = Occurrence.getNameRanges();
149     assert(NewName.getNamePieces().size() == Ranges.size() &&
150            "Mismatching number of ranges and name pieces");
151     AtomicChange Change(SM, Ranges[0].getBegin());
152     for (const auto &Range : llvm::enumerate(Ranges)) {
153       auto Error =
154           Change.replace(SM, CharSourceRange::getCharRange(Range.value()),
155                          NewName.getNamePieces()[Range.index()]);
156       if (Error)
157         return std::move(Error);
158     }
159     Changes.push_back(std::move(Change));
160   }
161   return std::move(Changes);
162 }
163 
164 /// Takes each atomic change and inserts its replacements into the set of
165 /// replacements that belong to the appropriate file.
166 static void convertChangesToFileReplacements(
167     ArrayRef<AtomicChange> AtomicChanges,
168     std::map<std::string, tooling::Replacements> *FileToReplaces) {
169   for (const auto &AtomicChange : AtomicChanges) {
170     for (const auto &Replace : AtomicChange.getReplacements()) {
171       llvm::Error Err = (*FileToReplaces)[Replace.getFilePath()].add(Replace);
172       if (Err) {
173         llvm::errs() << "Renaming failed in " << Replace.getFilePath() << "! "
174                      << llvm::toString(std::move(Err)) << "\n";
175       }
176     }
177   }
178 }
179 
180 class RenamingASTConsumer : public ASTConsumer {
181 public:
182   RenamingASTConsumer(
183       const std::vector<std::string> &NewNames,
184       const std::vector<std::string> &PrevNames,
185       const std::vector<std::vector<std::string>> &USRList,
186       std::map<std::string, tooling::Replacements> &FileToReplaces,
187       bool PrintLocations)
188       : NewNames(NewNames), PrevNames(PrevNames), USRList(USRList),
189         FileToReplaces(FileToReplaces), PrintLocations(PrintLocations) {}
190 
191   void HandleTranslationUnit(ASTContext &Context) override {
192     for (unsigned I = 0; I < NewNames.size(); ++I) {
193       // If the previous name was not found, ignore this rename request.
194       if (PrevNames[I].empty())
195         continue;
196 
197       HandleOneRename(Context, NewNames[I], PrevNames[I], USRList[I]);
198     }
199   }
200 
201   void HandleOneRename(ASTContext &Context, const std::string &NewName,
202                        const std::string &PrevName,
203                        const std::vector<std::string> &USRs) {
204     const SourceManager &SourceMgr = Context.getSourceManager();
205 
206     SymbolOccurrences Occurrences = tooling::getOccurrencesOfUSRs(
207         USRs, PrevName, Context.getTranslationUnitDecl());
208     if (PrintLocations) {
209       for (const auto &Occurrence : Occurrences) {
210         FullSourceLoc FullLoc(Occurrence.getNameRanges()[0].getBegin(),
211                               SourceMgr);
212         errs() << "clang-rename: renamed at: " << SourceMgr.getFilename(FullLoc)
213                << ":" << FullLoc.getSpellingLineNumber() << ":"
214                << FullLoc.getSpellingColumnNumber() << "\n";
215       }
216     }
217     // FIXME: Support multi-piece names.
218     // FIXME: better error handling (propagate error out).
219     SymbolName NewNameRef(NewName);
220     Expected<std::vector<AtomicChange>> Change =
221         createRenameReplacements(Occurrences, SourceMgr, NewNameRef);
222     if (!Change) {
223       llvm::errs() << "Failed to create renaming replacements for '" << PrevName
224                    << "'! " << llvm::toString(Change.takeError()) << "\n";
225       return;
226     }
227     convertChangesToFileReplacements(*Change, &FileToReplaces);
228   }
229 
230 private:
231   const std::vector<std::string> &NewNames, &PrevNames;
232   const std::vector<std::vector<std::string>> &USRList;
233   std::map<std::string, tooling::Replacements> &FileToReplaces;
234   bool PrintLocations;
235 };
236 
237 // A renamer to rename symbols which are identified by a give USRList to
238 // new name.
239 //
240 // FIXME: Merge with the above RenamingASTConsumer.
241 class USRSymbolRenamer : public ASTConsumer {
242 public:
243   USRSymbolRenamer(const std::vector<std::string> &NewNames,
244                    const std::vector<std::vector<std::string>> &USRList,
245                    std::map<std::string, tooling::Replacements> &FileToReplaces)
246       : NewNames(NewNames), USRList(USRList), FileToReplaces(FileToReplaces) {
247     assert(USRList.size() == NewNames.size());
248   }
249 
250   void HandleTranslationUnit(ASTContext &Context) override {
251     for (unsigned I = 0; I < NewNames.size(); ++I) {
252       // FIXME: Apply AtomicChanges directly once the refactoring APIs are
253       // ready.
254       auto AtomicChanges = tooling::createRenameAtomicChanges(
255           USRList[I], NewNames[I], Context.getTranslationUnitDecl());
256       convertChangesToFileReplacements(AtomicChanges, &FileToReplaces);
257     }
258   }
259 
260 private:
261   const std::vector<std::string> &NewNames;
262   const std::vector<std::vector<std::string>> &USRList;
263   std::map<std::string, tooling::Replacements> &FileToReplaces;
264 };
265 
266 std::unique_ptr<ASTConsumer> RenamingAction::newASTConsumer() {
267   return llvm::make_unique<RenamingASTConsumer>(NewNames, PrevNames, USRList,
268                                                 FileToReplaces, PrintLocations);
269 }
270 
271 std::unique_ptr<ASTConsumer> QualifiedRenamingAction::newASTConsumer() {
272   return llvm::make_unique<USRSymbolRenamer>(NewNames, USRList, FileToReplaces);
273 }
274 
275 } // end namespace tooling
276 } // end namespace clang
277