1 //===--- ReplaceDisallowCopyAndAssignMacroCheck.cpp - clang-tidy ----------===//
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 #include "ReplaceDisallowCopyAndAssignMacroCheck.h"
10 #include "clang/Frontend/CompilerInstance.h"
11 #include "clang/Lex/MacroArgs.h"
12 #include "clang/Lex/PPCallbacks.h"
13 #include "clang/Lex/Preprocessor.h"
14 #include "llvm/Support/FormatVariadic.h"
15 #include <optional>
16
17 namespace clang::tidy::modernize {
18
19 namespace {
20
21 class ReplaceDisallowCopyAndAssignMacroCallbacks : public PPCallbacks {
22 public:
ReplaceDisallowCopyAndAssignMacroCallbacks(ReplaceDisallowCopyAndAssignMacroCheck & Check,Preprocessor & PP)23 explicit ReplaceDisallowCopyAndAssignMacroCallbacks(
24 ReplaceDisallowCopyAndAssignMacroCheck &Check, Preprocessor &PP)
25 : Check(Check), PP(PP) {}
26
MacroExpands(const Token & MacroNameTok,const MacroDefinition & MD,SourceRange Range,const MacroArgs * Args)27 void MacroExpands(const Token &MacroNameTok, const MacroDefinition &MD,
28 SourceRange Range, const MacroArgs *Args) override {
29 IdentifierInfo *Info = MacroNameTok.getIdentifierInfo();
30 if (!Info || !Args || Args->getNumMacroArguments() != 1)
31 return;
32 if (Info->getName() != Check.getMacroName())
33 return;
34 // The first argument to the DISALLOW_COPY_AND_ASSIGN macro is expected to
35 // be the class name.
36 const Token *ClassNameTok = Args->getUnexpArgument(0);
37 if (Args->ArgNeedsPreexpansion(ClassNameTok, PP))
38 // For now we only support simple argument that don't need to be
39 // pre-expanded.
40 return;
41 clang::IdentifierInfo *ClassIdent = ClassNameTok->getIdentifierInfo();
42 if (!ClassIdent)
43 return;
44
45 std::string Replacement = llvm::formatv(
46 R"cpp({0}(const {0} &) = delete;
47 const {0} &operator=(const {0} &) = delete{1})cpp",
48 ClassIdent->getName(), shouldAppendSemi(Range) ? ";" : "");
49
50 Check.diag(MacroNameTok.getLocation(),
51 "prefer deleting copy constructor and assignment operator over "
52 "using macro '%0'")
53 << Check.getMacroName()
54 << FixItHint::CreateReplacement(
55 PP.getSourceManager().getExpansionRange(Range), Replacement);
56 }
57
58 private:
59 /// \returns \c true if the next token after the given \p MacroLoc is \b not a
60 /// semicolon.
shouldAppendSemi(SourceRange MacroLoc)61 bool shouldAppendSemi(SourceRange MacroLoc) {
62 std::optional<Token> Next = Lexer::findNextToken(
63 MacroLoc.getEnd(), PP.getSourceManager(), PP.getLangOpts());
64 return !(Next && Next->is(tok::semi));
65 }
66
67 ReplaceDisallowCopyAndAssignMacroCheck &Check;
68 Preprocessor &PP;
69 };
70 } // namespace
71
ReplaceDisallowCopyAndAssignMacroCheck(StringRef Name,ClangTidyContext * Context)72 ReplaceDisallowCopyAndAssignMacroCheck::ReplaceDisallowCopyAndAssignMacroCheck(
73 StringRef Name, ClangTidyContext *Context)
74 : ClangTidyCheck(Name, Context),
75 MacroName(Options.get("MacroName", "DISALLOW_COPY_AND_ASSIGN")) {}
76
registerPPCallbacks(const SourceManager & SM,Preprocessor * PP,Preprocessor * ModuleExpanderPP)77 void ReplaceDisallowCopyAndAssignMacroCheck::registerPPCallbacks(
78 const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) {
79 PP->addPPCallbacks(
80 ::std::make_unique<ReplaceDisallowCopyAndAssignMacroCallbacks>(
81 *this, *ModuleExpanderPP));
82 }
83
storeOptions(ClangTidyOptions::OptionMap & Opts)84 void ReplaceDisallowCopyAndAssignMacroCheck::storeOptions(
85 ClangTidyOptions::OptionMap &Opts) {
86 Options.store(Opts, "MacroName", MacroName);
87 }
88
89 } // namespace clang::tidy::modernize
90