1 //===--- ReplaceAutoPtrCheck.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 "ReplaceAutoPtrCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 #include "clang/Frontend/CompilerInstance.h"
13 #include "clang/Lex/Lexer.h"
14 #include "clang/Lex/Preprocessor.h"
15
16 using namespace clang;
17 using namespace clang::ast_matchers;
18
19 namespace clang::tidy::modernize {
20
21 namespace {
22 static const char AutoPtrTokenId[] = "AutoPrTokenId";
23 static const char AutoPtrOwnershipTransferId[] = "AutoPtrOwnershipTransferId";
24
25 /// Matches expressions that are lvalues.
26 ///
27 /// In the following example, a[0] matches expr(isLValue()):
28 /// \code
29 /// std::string a[2];
30 /// std::string b;
31 /// b = a[0];
32 /// b = "this string won't match";
33 /// \endcode
AST_MATCHER(Expr,isLValue)34 AST_MATCHER(Expr, isLValue) { return Node.getValueKind() == VK_LValue; }
35
36 } // namespace
37
ReplaceAutoPtrCheck(StringRef Name,ClangTidyContext * Context)38 ReplaceAutoPtrCheck::ReplaceAutoPtrCheck(StringRef Name,
39 ClangTidyContext *Context)
40 : ClangTidyCheck(Name, Context),
41 Inserter(Options.getLocalOrGlobal("IncludeStyle",
42 utils::IncludeSorter::IS_LLVM),
43 areDiagsSelfContained()) {}
44
storeOptions(ClangTidyOptions::OptionMap & Opts)45 void ReplaceAutoPtrCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
46 Options.store(Opts, "IncludeStyle", Inserter.getStyle());
47 }
48
registerMatchers(MatchFinder * Finder)49 void ReplaceAutoPtrCheck::registerMatchers(MatchFinder *Finder) {
50 auto AutoPtrDecl = recordDecl(hasName("auto_ptr"), isInStdNamespace());
51 auto AutoPtrType = qualType(hasDeclaration(AutoPtrDecl));
52
53 // std::auto_ptr<int> a;
54 // ^~~~~~~~~~~~~
55 //
56 // typedef std::auto_ptr<int> int_ptr_t;
57 // ^~~~~~~~~~~~~
58 //
59 // std::auto_ptr<int> fn(std::auto_ptr<int>);
60 // ^~~~~~~~~~~~~ ^~~~~~~~~~~~~
61 Finder->addMatcher(typeLoc(loc(qualType(AutoPtrType,
62 // Skip elaboratedType() as the named
63 // type will match soon thereafter.
64 unless(elaboratedType()))))
65 .bind(AutoPtrTokenId),
66 this);
67
68 // using std::auto_ptr;
69 // ^~~~~~~~~~~~~~~~~~~
70 Finder->addMatcher(usingDecl(hasAnyUsingShadowDecl(hasTargetDecl(namedDecl(
71 hasName("auto_ptr"), isInStdNamespace()))))
72 .bind(AutoPtrTokenId),
73 this);
74
75 // Find ownership transfers via copy construction and assignment.
76 // AutoPtrOwnershipTransferId is bound to the part that has to be wrapped
77 // into std::move().
78 // std::auto_ptr<int> i, j;
79 // i = j;
80 // ~~~~^
81 auto MovableArgumentMatcher =
82 expr(isLValue(), hasType(AutoPtrType)).bind(AutoPtrOwnershipTransferId);
83
84 Finder->addMatcher(
85 cxxOperatorCallExpr(hasOverloadedOperatorName("="),
86 callee(cxxMethodDecl(ofClass(AutoPtrDecl))),
87 hasArgument(1, MovableArgumentMatcher)),
88 this);
89 Finder->addMatcher(
90 traverse(TK_AsIs,
91 cxxConstructExpr(hasType(AutoPtrType), argumentCountIs(1),
92 hasArgument(0, MovableArgumentMatcher))),
93 this);
94 }
95
registerPPCallbacks(const SourceManager & SM,Preprocessor * PP,Preprocessor * ModuleExpanderPP)96 void ReplaceAutoPtrCheck::registerPPCallbacks(const SourceManager &SM,
97 Preprocessor *PP,
98 Preprocessor *ModuleExpanderPP) {
99 Inserter.registerPreprocessor(PP);
100 }
101
check(const MatchFinder::MatchResult & Result)102 void ReplaceAutoPtrCheck::check(const MatchFinder::MatchResult &Result) {
103 SourceManager &SM = *Result.SourceManager;
104 if (const auto *E =
105 Result.Nodes.getNodeAs<Expr>(AutoPtrOwnershipTransferId)) {
106 CharSourceRange Range = Lexer::makeFileCharRange(
107 CharSourceRange::getTokenRange(E->getSourceRange()), SM, LangOptions());
108
109 if (Range.isInvalid())
110 return;
111
112 auto Diag = diag(Range.getBegin(), "use std::move to transfer ownership")
113 << FixItHint::CreateInsertion(Range.getBegin(), "std::move(")
114 << FixItHint::CreateInsertion(Range.getEnd(), ")")
115 << Inserter.createMainFileIncludeInsertion("<utility>");
116
117 return;
118 }
119
120 SourceLocation AutoPtrLoc;
121 if (const auto *TL = Result.Nodes.getNodeAs<TypeLoc>(AutoPtrTokenId)) {
122 // std::auto_ptr<int> i;
123 // ^
124 if (auto Loc = TL->getAs<TemplateSpecializationTypeLoc>())
125 AutoPtrLoc = Loc.getTemplateNameLoc();
126 } else if (const auto *D =
127 Result.Nodes.getNodeAs<UsingDecl>(AutoPtrTokenId)) {
128 // using std::auto_ptr;
129 // ^
130 AutoPtrLoc = D->getNameInfo().getBeginLoc();
131 } else {
132 llvm_unreachable("Bad Callback. No node provided.");
133 }
134
135 if (AutoPtrLoc.isMacroID())
136 AutoPtrLoc = SM.getSpellingLoc(AutoPtrLoc);
137
138 // Ensure that only the 'auto_ptr' token is replaced and not the template
139 // aliases.
140 if (StringRef(SM.getCharacterData(AutoPtrLoc), strlen("auto_ptr")) !=
141 "auto_ptr")
142 return;
143
144 SourceLocation EndLoc =
145 AutoPtrLoc.getLocWithOffset(strlen("auto_ptr") - 1);
146 diag(AutoPtrLoc, "auto_ptr is deprecated, use unique_ptr instead")
147 << FixItHint::CreateReplacement(SourceRange(AutoPtrLoc, EndLoc),
148 "unique_ptr");
149 }
150
151 } // namespace clang::tidy::modernize
152