clang-tools  5.0.0
ReplaceAutoPtrCheck.cpp
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1 //===--- ReplaceAutoPtrCheck.cpp - clang-tidy------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "ReplaceAutoPtrCheck.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 #include "clang/Frontend/CompilerInstance.h"
14 #include "clang/Lex/Lexer.h"
15 #include "clang/Lex/Preprocessor.h"
16 
17 using namespace clang;
18 using namespace clang::ast_matchers;
19 
20 namespace clang {
21 namespace tidy {
22 namespace modernize {
23 
24 static const char AutoPtrTokenId[] = "AutoPrTokenId";
25 static const char AutoPtrOwnershipTransferId[] = "AutoPtrOwnershipTransferId";
26 
27 /// \brief 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 ReplaceAutoPtrCheck::ReplaceAutoPtrCheck(StringRef Name,
73  ClangTidyContext *Context)
74  : ClangTidyCheck(Name, Context),
75  IncludeStyle(utils::IncludeSorter::parseIncludeStyle(
76  Options.get("IncludeStyle", "llvm"))) {}
77 
79  Options.store(Opts, "IncludeStyle",
80  utils::IncludeSorter::toString(IncludeStyle));
81 }
82 
84  // Only register the matchers for C++; the functionality currently does not
85  // provide any benefit to other languages, despite being benign.
86  if (!getLangOpts().CPlusPlus)
87  return;
88 
89  auto AutoPtrDecl = recordDecl(hasName("auto_ptr"), isFromStdNamespace());
90  auto AutoPtrType = qualType(hasDeclaration(AutoPtrDecl));
91 
92  // std::auto_ptr<int> a;
93  // ^~~~~~~~~~~~~
94  //
95  // typedef std::auto_ptr<int> int_ptr_t;
96  // ^~~~~~~~~~~~~
97  //
98  // std::auto_ptr<int> fn(std::auto_ptr<int>);
99  // ^~~~~~~~~~~~~ ^~~~~~~~~~~~~
100  Finder->addMatcher(typeLoc(loc(qualType(AutoPtrType,
101  // Skip elaboratedType() as the named
102  // type will match soon thereafter.
103  unless(elaboratedType()))))
104  .bind(AutoPtrTokenId),
105  this);
106 
107  // using std::auto_ptr;
108  // ^~~~~~~~~~~~~~~~~~~
109  Finder->addMatcher(usingDecl(hasAnyUsingShadowDecl(hasTargetDecl(allOf(
110  hasName("auto_ptr"), isFromStdNamespace()))))
111  .bind(AutoPtrTokenId),
112  this);
113 
114  // Find ownership transfers via copy construction and assignment.
115  // AutoPtrOwnershipTransferId is bound to the the part that has to be wrapped
116  // into std::move().
117  // std::auto_ptr<int> i, j;
118  // i = j;
119  // ~~~~^
120  auto MovableArgumentMatcher =
121  expr(isLValue(), hasType(AutoPtrType)).bind(AutoPtrOwnershipTransferId);
122 
123  Finder->addMatcher(
124  cxxOperatorCallExpr(hasOverloadedOperatorName("="),
125  callee(cxxMethodDecl(ofClass(AutoPtrDecl))),
126  hasArgument(1, MovableArgumentMatcher)),
127  this);
128  Finder->addMatcher(cxxConstructExpr(hasType(AutoPtrType), argumentCountIs(1),
129  hasArgument(0, MovableArgumentMatcher)),
130  this);
131 }
132 
133 void ReplaceAutoPtrCheck::registerPPCallbacks(CompilerInstance &Compiler) {
134  // Only register the preprocessor callbacks for C++; the functionality
135  // currently does not provide any benefit to other languages, despite being
136  // benign.
137  if (!getLangOpts().CPlusPlus)
138  return;
139  Inserter.reset(new utils::IncludeInserter(
140  Compiler.getSourceManager(), Compiler.getLangOpts(), IncludeStyle));
141  Compiler.getPreprocessor().addPPCallbacks(Inserter->CreatePPCallbacks());
142 }
143 
144 void ReplaceAutoPtrCheck::check(const MatchFinder::MatchResult &Result) {
145  SourceManager &SM = *Result.SourceManager;
146  if (const auto *E =
147  Result.Nodes.getNodeAs<Expr>(AutoPtrOwnershipTransferId)) {
148  CharSourceRange Range = Lexer::makeFileCharRange(
149  CharSourceRange::getTokenRange(E->getSourceRange()), SM, LangOptions());
150 
151  if (Range.isInvalid())
152  return;
153 
154  auto Diag = diag(Range.getBegin(), "use std::move to transfer ownership")
155  << FixItHint::CreateInsertion(Range.getBegin(), "std::move(")
156  << FixItHint::CreateInsertion(Range.getEnd(), ")");
157 
158  if (auto Fix =
159  Inserter->CreateIncludeInsertion(SM.getMainFileID(), "utility",
160  /*IsAngled=*/true))
161  Diag << *Fix;
162 
163  return;
164  }
165 
166  SourceLocation AutoPtrLoc;
167  if (const auto *TL = Result.Nodes.getNodeAs<TypeLoc>(AutoPtrTokenId)) {
168  // std::auto_ptr<int> i;
169  // ^
170  if (auto Loc = TL->getAs<TemplateSpecializationTypeLoc>())
171  AutoPtrLoc = Loc.getTemplateNameLoc();
172  } else if (const auto *D =
173  Result.Nodes.getNodeAs<UsingDecl>(AutoPtrTokenId)) {
174  // using std::auto_ptr;
175  // ^
176  AutoPtrLoc = D->getNameInfo().getBeginLoc();
177  } else {
178  llvm_unreachable("Bad Callback. No node provided.");
179  }
180 
181  if (AutoPtrLoc.isMacroID())
182  AutoPtrLoc = SM.getSpellingLoc(AutoPtrLoc);
183 
184  // Ensure that only the 'auto_ptr' token is replaced and not the template
185  // aliases.
186  if (StringRef(SM.getCharacterData(AutoPtrLoc), strlen("auto_ptr")) !=
187  "auto_ptr")
188  return;
189 
190  SourceLocation EndLoc =
191  AutoPtrLoc.getLocWithOffset(strlen("auto_ptr") - 1);
192  diag(AutoPtrLoc, "auto_ptr is deprecated, use unique_ptr instead")
193  << FixItHint::CreateReplacement(SourceRange(AutoPtrLoc, EndLoc),
194  "unique_ptr");
195 }
196 
197 } // namespace modernize
198 } // namespace tidy
199 } // namespace clang
SourceLocation Loc
'#' location in the include directive
LangOptions getLangOpts() const
Returns the language options from the context.
Definition: ClangTidy.h:187
StringHandle Name
std::unique_ptr< ast_matchers::MatchFinder > Finder
Definition: ClangTidy.cpp:275
static StringRef toString(IncludeStyle Style)
Converts IncludeStyle to string representation.
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
SourceManager & SM
void store(ClangTidyOptions::OptionMap &Options, StringRef LocalName, StringRef Value) const
Stores an option with the check-local name LocalName with string value Value to Options.
Definition: ClangTidy.cpp:449
std::map< std::string, std::string > OptionMap
void registerPPCallbacks(CompilerInstance &Compiler) override
Override this to register PPCallbacks with Compiler.
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
CharSourceRange Range
SourceRange for the file name.
void storeOptions(ClangTidyOptions::OptionMap &Opts) override
Should store all options supported by this check with their current values or default values for opti...
ClangTidyContext & Context
Definition: ClangTidy.cpp:87
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))
AST_MATCHER(VarDecl, isAsm)
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check's name.
Definition: ClangTidy.cpp:416