clang-tools-extra/clang-tidy/modernize/DeprecatedIosBaseAliasesCheck.cpp

   1 //===--- DeprecatedIosBaseAliasesCheck.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 "DeprecatedIosBaseAliasesCheck.h"
  10 #include "clang/AST/ASTContext.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12 #include <optional>
  13
  14 using namespace clang::ast_matchers;
  15
  16 namespace clang::tidy::modernize {
  17
  18 static constexpr std::array<StringRef, 5> DeprecatedTypes = {
  19     "::std::ios_base::io_state", "::std::ios_base::open_mode",
  20     "::std::ios_base::seek_dir", "::std::ios_base::streamoff",
  21     "::std::ios_base::streampos"};
  22
  23 static std::optional<const char *> getReplacementType(StringRef Type) {
  24   return llvm::StringSwitch<std::optional<const char *>>(Type)
  25       .Case("io_state", "iostate")
  26       .Case("open_mode", "openmode")
  27       .Case("seek_dir", "seekdir")
  28       .Default(std::nullopt);
  29 }
  30
  31 void DeprecatedIosBaseAliasesCheck::registerMatchers(MatchFinder *Finder) {
  32   auto IoStateDecl = typedefDecl(hasAnyName(DeprecatedTypes)).bind("TypeDecl");
  33   auto IoStateType =
  34       qualType(hasDeclaration(IoStateDecl), unless(elaboratedType()));
  35
  36   Finder->addMatcher(typeLoc(loc(IoStateType)).bind("TypeLoc"), this);
  37 }
  38
  39 void DeprecatedIosBaseAliasesCheck::check(
  40     const MatchFinder::MatchResult &Result) {
  41   SourceManager &SM = *Result.SourceManager;
  42
  43   const auto *Typedef = Result.Nodes.getNodeAs<TypedefDecl>("TypeDecl");
  44   StringRef TypeName = Typedef->getName();
  45   auto Replacement = getReplacementType(TypeName);
  46
  47   const auto *TL = Result.Nodes.getNodeAs<TypeLoc>("TypeLoc");
  48   SourceLocation IoStateLoc = TL->getBeginLoc();
  49
  50   // Do not generate fixits for matches depending on template arguments and
  51   // macro expansions.
  52   bool Fix = Replacement && !TL->getType()->isDependentType();
  53   if (IoStateLoc.isMacroID()) {
  54     IoStateLoc = SM.getSpellingLoc(IoStateLoc);
  55     Fix = false;
  56   }
  57
  58   SourceLocation EndLoc = IoStateLoc.getLocWithOffset(TypeName.size() - 1);
  59
  60   if (Replacement) {
  61     const char *FixName = *Replacement;
  62     auto Builder = diag(IoStateLoc, "'std::ios_base::%0' is deprecated; use "
  63                                     "'std::ios_base::%1' instead")
  64                    << TypeName << FixName;
  65
  66     if (Fix)
  67       Builder << FixItHint::CreateReplacement(SourceRange(IoStateLoc, EndLoc),
  68                                               FixName);
  69   } else
  70     diag(IoStateLoc, "'std::ios_base::%0' is deprecated") << TypeName;
  71 }
  72
  73 } // namespace clang::tidy::modernize