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

   1 //===--- ReplaceRandomShuffleCheck.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 "ReplaceRandomShuffleCheck.h"
  10 #include "../utils/FixItHintUtils.h"
  11 #include "clang/AST/ASTContext.h"
  12 #include "clang/ASTMatchers/ASTMatchFinder.h"
  13 #include "clang/Frontend/CompilerInstance.h"
  14 #include "clang/Lex/Preprocessor.h"
  15 #include "clang/Tooling/FixIt.h"
  16
  17 using namespace clang::ast_matchers;
  18
  19 namespace clang::tidy::modernize {
  20
  21 ReplaceRandomShuffleCheck::ReplaceRandomShuffleCheck(StringRef Name,
  22                                                      ClangTidyContext *Context)
  23     : ClangTidyCheck(Name, Context),
  24       IncludeInserter(Options.getLocalOrGlobal("IncludeStyle",
  25                                                utils::IncludeSorter::IS_LLVM),
  26                       areDiagsSelfContained()) {}
  27
  28 void ReplaceRandomShuffleCheck::registerMatchers(MatchFinder *Finder) {
  29   const auto Begin = hasArgument(0, expr());
  30   const auto End = hasArgument(1, expr());
  31   const auto RandomFunc = hasArgument(2, expr().bind("randomFunc"));
  32   Finder->addMatcher(
  33       traverse(
  34           TK_AsIs,
  35           callExpr(
  36               anyOf(allOf(Begin, End, argumentCountIs(2)),
  37                     allOf(Begin, End, RandomFunc, argumentCountIs(3))),
  38               hasDeclaration(functionDecl(hasName("::std::random_shuffle"))),
  39               has(implicitCastExpr(has(declRefExpr().bind("name")))))
  40               .bind("match")),
  41       this);
  42 }
  43
  44 void ReplaceRandomShuffleCheck::registerPPCallbacks(
  45     const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) {
  46   IncludeInserter.registerPreprocessor(PP);
  47 }
  48
  49 void ReplaceRandomShuffleCheck::storeOptions(
  50     ClangTidyOptions::OptionMap &Opts) {
  51   Options.store(Opts, "IncludeStyle", IncludeInserter.getStyle());
  52 }
  53
  54 void ReplaceRandomShuffleCheck::check(const MatchFinder::MatchResult &Result) {
  55   const auto *MatchedDecl = Result.Nodes.getNodeAs<DeclRefExpr>("name");
  56   const auto *MatchedArgumentThree = Result.Nodes.getNodeAs<Expr>("randomFunc");
  57   const auto *MatchedCallExpr = Result.Nodes.getNodeAs<CallExpr>("match");
  58
  59   if (MatchedCallExpr->getBeginLoc().isMacroID())
  60     return;
  61
  62   auto Diag = [&] {
  63     if (MatchedCallExpr->getNumArgs() == 3) {
  64       auto DiagL =
  65           diag(MatchedCallExpr->getBeginLoc(),
  66                "'std::random_shuffle' has been removed in C++17; use "
  67                "'std::shuffle' and an alternative random mechanism instead");
  68       DiagL << FixItHint::CreateReplacement(
  69           MatchedArgumentThree->getSourceRange(),
  70           "std::mt19937(std::random_device()())");
  71       return DiagL;
  72     }
  73     auto DiagL = diag(MatchedCallExpr->getBeginLoc(),
  74                       "'std::random_shuffle' has been removed in C++17; use "
  75                       "'std::shuffle' instead");
  76     DiagL << FixItHint::CreateInsertion(
  77         MatchedCallExpr->getRParenLoc(),
  78         ", std::mt19937(std::random_device()())");
  79     return DiagL;
  80   }();
  81
  82   std::string NewName = "shuffle";
  83   StringRef ContainerText = Lexer::getSourceText(
  84       CharSourceRange::getTokenRange(MatchedDecl->getSourceRange()),
  85       *Result.SourceManager, getLangOpts());
  86   if (ContainerText.startswith("std::"))
  87     NewName = "std::" + NewName;
  88
  89   Diag << FixItHint::CreateRemoval(MatchedDecl->getSourceRange());
  90   Diag << FixItHint::CreateInsertion(MatchedDecl->getBeginLoc(), NewName);
  91   Diag << IncludeInserter.createIncludeInsertion(
  92       Result.Context->getSourceManager().getFileID(
  93           MatchedCallExpr->getBeginLoc()),
  94       "<random>");
  95 }
  96
  97 } // namespace clang::tidy::modernize