clang-tools  10.0.0git
ReplaceAutoPtrCheck.cpp
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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 {
20 namespace tidy {
21 namespace modernize {
22 
23 namespace {
24 static const char AutoPtrTokenId[] = "AutoPrTokenId";
25 static const char AutoPtrOwnershipTransferId[] = "AutoPtrOwnershipTransferId";
26 
27 /// Matches expressions that are lvalues.
28 ///
29 /// In the following example, a[0] matches expr(isLValue()):
30 /// \code
31 /// std::string a[2];
32 /// std::string b;
33 /// b = a[0];
34 /// b = "this string won't match";
35 /// \endcode
36 AST_MATCHER(Expr, isLValue) { return Node.getValueKind() == VK_LValue; }
37 
38 /// Matches declarations whose declaration context is the C++ standard library
39 /// namespace std.
40 ///
41 /// Note that inline namespaces are silently ignored during the lookup since
42 /// both libstdc++ and libc++ are known to use them for versioning purposes.
43 ///
44 /// Given:
45 /// \code
46 /// namespace ns {
47 /// struct my_type {};
48 /// using namespace std;
49 /// }
50 ///
51 /// using std::vector;
52 /// using ns:my_type;
53 /// using ns::list;
54 /// \code
55 ///
56 /// usingDecl(hasAnyUsingShadowDecl(hasTargetDecl(isFromStdNamespace())))
57 /// matches "using std::vector" and "using ns::list".
58 AST_MATCHER(Decl, isFromStdNamespace) {
59  const DeclContext *D = Node.getDeclContext();
60 
61  while (D->isInlineNamespace())
62  D = D->getParent();
63 
64  if (!D->isNamespace() || !D->getParent()->isTranslationUnit())
65  return false;
66 
67  const IdentifierInfo *Info = cast<NamespaceDecl>(D)->getIdentifier();
68 
69  return (Info && Info->isStr("std"));
70 }
71 
72 } // namespace
73 
74 ReplaceAutoPtrCheck::ReplaceAutoPtrCheck(StringRef Name,
75  ClangTidyContext *Context)
76  : ClangTidyCheck(Name, Context),
77  IncludeStyle(utils::IncludeSorter::parseIncludeStyle(
78  Options.getLocalOrGlobal("IncludeStyle", "llvm"))) {}
79 
80 void ReplaceAutoPtrCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
81  Options.store(Opts, "IncludeStyle",
82  utils::IncludeSorter::toString(IncludeStyle));
83 }
84 
85 void ReplaceAutoPtrCheck::registerMatchers(MatchFinder *Finder) {
86  // Only register the matchers for C++; the functionality currently does not
87  // provide any benefit to other languages, despite being benign.
88  if (!getLangOpts().CPlusPlus)
89  return;
90 
91  auto AutoPtrDecl = recordDecl(hasName("auto_ptr"), isFromStdNamespace());
92  auto AutoPtrType = qualType(hasDeclaration(AutoPtrDecl));
93 
94  // std::auto_ptr<int> a;
95  // ^~~~~~~~~~~~~
96  //
97  // typedef std::auto_ptr<int> int_ptr_t;
98  // ^~~~~~~~~~~~~
99  //
100  // std::auto_ptr<int> fn(std::auto_ptr<int>);
101  // ^~~~~~~~~~~~~ ^~~~~~~~~~~~~
102  Finder->addMatcher(typeLoc(loc(qualType(AutoPtrType,
103  // Skip elaboratedType() as the named
104  // type will match soon thereafter.
105  unless(elaboratedType()))))
106  .bind(AutoPtrTokenId),
107  this);
108 
109  // using std::auto_ptr;
110  // ^~~~~~~~~~~~~~~~~~~
111  Finder->addMatcher(usingDecl(hasAnyUsingShadowDecl(hasTargetDecl(namedDecl(
112  hasName("auto_ptr"), isFromStdNamespace()))))
113  .bind(AutoPtrTokenId),
114  this);
115 
116  // Find ownership transfers via copy construction and assignment.
117  // AutoPtrOwnershipTransferId is bound to the part that has to be wrapped
118  // into std::move().
119  // std::auto_ptr<int> i, j;
120  // i = j;
121  // ~~~~^
122  auto MovableArgumentMatcher =
123  expr(isLValue(), hasType(AutoPtrType)).bind(AutoPtrOwnershipTransferId);
124 
125  Finder->addMatcher(
126  cxxOperatorCallExpr(hasOverloadedOperatorName("="),
127  callee(cxxMethodDecl(ofClass(AutoPtrDecl))),
128  hasArgument(1, MovableArgumentMatcher)),
129  this);
130  Finder->addMatcher(cxxConstructExpr(hasType(AutoPtrType), argumentCountIs(1),
131  hasArgument(0, MovableArgumentMatcher)),
132  this);
133 }
134 
135 void ReplaceAutoPtrCheck::registerPPCallbacks(const SourceManager &SM,
136  Preprocessor *PP,
137  Preprocessor *ModuleExpanderPP) {
138  // Only register the preprocessor callbacks for C++; the functionality
139  // currently does not provide any benefit to other languages, despite being
140  // benign.
141  if (!getLangOpts().CPlusPlus)
142  return;
143  Inserter = std::make_unique<utils::IncludeInserter>(SM, getLangOpts(),
144  IncludeStyle);
145  PP->addPPCallbacks(Inserter->CreatePPCallbacks());
146 }
147 
148 void ReplaceAutoPtrCheck::check(const MatchFinder::MatchResult &Result) {
149  SourceManager &SM = *Result.SourceManager;
150  if (const auto *E =
151  Result.Nodes.getNodeAs<Expr>(AutoPtrOwnershipTransferId)) {
152  CharSourceRange Range = Lexer::makeFileCharRange(
153  CharSourceRange::getTokenRange(E->getSourceRange()), SM, LangOptions());
154 
155  if (Range.isInvalid())
156  return;
157 
158  auto Diag = diag(Range.getBegin(), "use std::move to transfer ownership")
159  << FixItHint::CreateInsertion(Range.getBegin(), "std::move(")
160  << FixItHint::CreateInsertion(Range.getEnd(), ")");
161 
162  if (auto Fix =
163  Inserter->CreateIncludeInsertion(SM.getMainFileID(), "utility",
164  /*IsAngled=*/true))
165  Diag << *Fix;
166 
167  return;
168  }
169 
170  SourceLocation AutoPtrLoc;
171  if (const auto *TL = Result.Nodes.getNodeAs<TypeLoc>(AutoPtrTokenId)) {
172  // std::auto_ptr<int> i;
173  // ^
174  if (auto Loc = TL->getAs<TemplateSpecializationTypeLoc>())
175  AutoPtrLoc = Loc.getTemplateNameLoc();
176  } else if (const auto *D =
177  Result.Nodes.getNodeAs<UsingDecl>(AutoPtrTokenId)) {
178  // using std::auto_ptr;
179  // ^
180  AutoPtrLoc = D->getNameInfo().getBeginLoc();
181  } else {
182  llvm_unreachable("Bad Callback. No node provided.");
183  }
184 
185  if (AutoPtrLoc.isMacroID())
186  AutoPtrLoc = SM.getSpellingLoc(AutoPtrLoc);
187 
188  // Ensure that only the 'auto_ptr' token is replaced and not the template
189  // aliases.
190  if (StringRef(SM.getCharacterData(AutoPtrLoc), strlen("auto_ptr")) !=
191  "auto_ptr")
192  return;
193 
194  SourceLocation EndLoc =
195  AutoPtrLoc.getLocWithOffset(strlen("auto_ptr") - 1);
196  diag(AutoPtrLoc, "auto_ptr is deprecated, use unique_ptr instead")
197  << FixItHint::CreateReplacement(SourceRange(AutoPtrLoc, EndLoc),
198  "unique_ptr");
199 }
200 
201 } // namespace modernize
202 } // namespace tidy
203 } // namespace clang
SourceLocation Loc
&#39;#&#39; location in the include directive
const FunctionDecl * Decl
static llvm::StringRef toString(SpecialMemberFunctionsCheck::SpecialMemberFunctionKind K)
static constexpr llvm::StringLiteral Name
llvm::Optional< Range > getTokenRange(const SourceManager &SM, const LangOptions &LangOpts, SourceLocation TokLoc)
Returns the taken range at TokLoc.
Definition: SourceCode.cpp:227
FunctionInfo Info
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
CharSourceRange Range
SourceRange for the file name.
const Expr * E
static cl::opt< bool > Fix("fix", cl::desc(R"( Apply suggested fixes. Without -fix-errors clang-tidy will bail out if any compilation errors were found. )"), cl::init(false), cl::cat(ClangTidyCategory))