1//===-- ClangChangeNamespace.cpp - Standalone change namespace ------------===//
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// This tool can be used to change the surrounding namespaces of class/function
9// definitions.
10//
11// Example: test.cc
12// namespace na {
13// class X {};
14// namespace nb {
15// class Y { X x; };
16// } // namespace nb
17// } // namespace na
18// To move the definition of class Y from namespace "na::nb" to "x::y", run:
19// clang-change-namespace --old_namespace "na::nb" \
20// --new_namespace "x::y" --file_pattern "test.cc" test.cc --
21// Output:
22// namespace na {
23// class X {};
24// } // namespace na
25// namespace x {
26// namespace y {
27// class Y { na::X x; };
28// } // namespace y
29// } // namespace x
30
31#include "ChangeNamespace.h"
32#include "clang/ASTMatchers/ASTMatchFinder.h"
33#include "clang/Frontend/FrontendActions.h"
34#include "clang/Frontend/TextDiagnosticPrinter.h"
35#include "clang/Rewrite/Core/Rewriter.h"
36#include "clang/Tooling/CommonOptionsParser.h"
37#include "clang/Tooling/Refactoring.h"
38#include "clang/Tooling/Tooling.h"
39#include "llvm/Support/CommandLine.h"
40#include "llvm/Support/Signals.h"
41#include "llvm/Support/YAMLTraits.h"
42
43using namespace clang;
44using namespace llvm;
45
46namespace {
47
48cl::OptionCategory ChangeNamespaceCategory("Change namespace.");
49
50cl::opt<std::string> OldNamespace("old_namespace", cl::Required,
51 cl::desc("Old namespace."),
52 cl::cat(ChangeNamespaceCategory));
53
54cl::opt<std::string> NewNamespace("new_namespace", cl::Required,
55 cl::desc("New namespace."),
56 cl::cat(ChangeNamespaceCategory));
57
58cl::opt<std::string> FilePattern(
59 "file_pattern", cl::Required,
60 cl::desc("Only rename namespaces in files that match the given pattern."),
61 cl::cat(ChangeNamespaceCategory));
62
63cl::opt<bool> Inplace("i", cl::desc("Inplace edit <file>s, if specified."),
64 cl::cat(ChangeNamespaceCategory));
65
66cl::opt<bool>
67 DumpYAML("dump_result",
68 cl::desc("Dump new file contents in YAML, if specified."),
69 cl::cat(ChangeNamespaceCategory));
70
71cl::opt<std::string> Style("style",
72 cl::desc("The style name used for reformatting."),
73 cl::init(Val: "LLVM"), cl::cat(ChangeNamespaceCategory));
74
75cl::opt<std::string> AllowedFile(
76 "allowed_file",
77 cl::desc("A file containing regexes of symbol names that are not expected "
78 "to be updated when changing namespaces around them."),
79 cl::init(Val: ""), cl::cat(ChangeNamespaceCategory));
80
81llvm::ErrorOr<std::vector<std::string>> GetAllowedSymbolPatterns() {
82 std::vector<std::string> Patterns;
83 if (AllowedFile.empty())
84 return Patterns;
85
86 llvm::SmallVector<StringRef, 8> Lines;
87 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
88 llvm::MemoryBuffer::getFile(Filename: AllowedFile);
89 if (!File)
90 return File.getError();
91 llvm::StringRef Content = File.get()->getBuffer();
92 Content.split(A&: Lines, Separator: '\n', /*MaxSplit=*/-1, /*KeepEmpty=*/false);
93 for (auto Line : Lines)
94 Patterns.push_back(x: std::string(Line.trim()));
95 return Patterns;
96}
97
98} // anonymous namespace
99
100int main(int argc, const char **argv) {
101 llvm::sys::PrintStackTraceOnErrorSignal(Argv0: argv[0]);
102 auto ExpectedParser =
103 tooling::CommonOptionsParser::create(argc, argv, Category&: ChangeNamespaceCategory);
104 if (!ExpectedParser) {
105 llvm::errs() << ExpectedParser.takeError();
106 return 1;
107 }
108 tooling::CommonOptionsParser &OptionsParser = ExpectedParser.get();
109 const auto &Files = OptionsParser.getSourcePathList();
110 tooling::RefactoringTool Tool(OptionsParser.getCompilations(), Files);
111 llvm::ErrorOr<std::vector<std::string>> AllowedPatterns =
112 GetAllowedSymbolPatterns();
113 if (!AllowedPatterns) {
114 llvm::errs() << "Failed to open allow file " << AllowedFile << ". "
115 << AllowedPatterns.getError().message() << "\n";
116 return 1;
117 }
118 change_namespace::ChangeNamespaceTool NamespaceTool(
119 OldNamespace, NewNamespace, FilePattern, *AllowedPatterns,
120 &Tool.getReplacements(), Style);
121 ast_matchers::MatchFinder Finder;
122 NamespaceTool.registerMatchers(Finder: &Finder);
123 std::unique_ptr<tooling::FrontendActionFactory> Factory =
124 tooling::newFrontendActionFactory(ConsumerFactory: &Finder);
125
126 if (int Result = Tool.run(Action: Factory.get()))
127 return Result;
128 LangOptions DefaultLangOptions;
129 DiagnosticOptions DiagOpts;
130 clang::TextDiagnosticPrinter DiagnosticPrinter(errs(), DiagOpts);
131 DiagnosticsEngine Diagnostics(
132 IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs()), DiagOpts,
133 &DiagnosticPrinter, false);
134 auto &FileMgr = Tool.getFiles();
135 SourceManager Sources(Diagnostics, FileMgr);
136 Rewriter Rewrite(Sources, DefaultLangOptions);
137
138 if (!formatAndApplyAllReplacements(FileToReplaces: Tool.getReplacements(), Rewrite, Style)) {
139 llvm::errs() << "Failed applying all replacements.\n";
140 return 1;
141 }
142 if (Inplace)
143 return Rewrite.overwriteChangedFiles();
144
145 std::set<llvm::StringRef> ChangedFiles;
146 for (const auto &it : Tool.getReplacements())
147 ChangedFiles.insert(x: it.first);
148
149 if (DumpYAML) {
150 auto WriteToYAML = [&](llvm::raw_ostream &OS) {
151 OS << "[\n";
152 for (auto I = ChangedFiles.begin(), E = ChangedFiles.end(); I != E; ++I) {
153 OS << " {\n";
154 OS << " \"FilePath\": \"" << *I << "\",\n";
155 auto Entry = llvm::cantFail(ValOrErr: FileMgr.getFileRef(Filename: *I));
156 auto ID = Sources.getOrCreateFileID(SourceFile: Entry, FileCharacter: SrcMgr::C_User);
157 std::string Content;
158 llvm::raw_string_ostream ContentStream(Content);
159 Rewrite.getEditBuffer(FID: ID).write(Stream&: ContentStream);
160 OS << " \"SourceText\": \""
161 << llvm::yaml::escape(Input: ContentStream.str()) << "\"\n";
162 OS << " }";
163 if (I != std::prev(x: E))
164 OS << ",\n";
165 }
166 OS << "\n]\n";
167 };
168 WriteToYAML(llvm::outs());
169 return 0;
170 }
171
172 for (const auto &File : ChangedFiles) {
173 auto Entry = llvm::cantFail(ValOrErr: FileMgr.getFileRef(Filename: File));
174
175 auto ID = Sources.getOrCreateFileID(SourceFile: Entry, FileCharacter: SrcMgr::C_User);
176 outs() << "============== " << File << " ==============\n";
177 Rewrite.getEditBuffer(FID: ID).write(Stream&: llvm::outs());
178 outs() << "\n============================================\n";
179 }
180
181 return 0;
182}
183

source code of clang-tools-extra/clang-change-namespace/tool/ClangChangeNamespace.cpp