xref: /llvm-project/clang-tools-extra/clang-tidy/modernize/ReplaceRandomShuffleCheck.cpp (revision b859c39c40a79ff74033f67d807a18130b9afe30)
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 {
20 namespace tidy {
21 namespace modernize {
22 
23 ReplaceRandomShuffleCheck::ReplaceRandomShuffleCheck(StringRef Name,
24                                                      ClangTidyContext *Context)
25     : ClangTidyCheck(Name, Context),
26       IncludeInserter(Options.getLocalOrGlobal("IncludeStyle",
27                                                utils::IncludeSorter::IS_LLVM),
28                       areDiagsSelfContained()) {}
29 
30 void ReplaceRandomShuffleCheck::registerMatchers(MatchFinder *Finder) {
31   const auto Begin = hasArgument(0, expr());
32   const auto End = hasArgument(1, expr());
33   const auto RandomFunc = hasArgument(2, expr().bind("randomFunc"));
34   Finder->addMatcher(
35       traverse(
36           TK_AsIs,
37           callExpr(
38               anyOf(allOf(Begin, End, argumentCountIs(2)),
39                     allOf(Begin, End, RandomFunc, argumentCountIs(3))),
40               hasDeclaration(functionDecl(hasName("::std::random_shuffle"))),
41               has(implicitCastExpr(has(declRefExpr().bind("name")))))
42               .bind("match")),
43       this);
44 }
45 
46 void ReplaceRandomShuffleCheck::registerPPCallbacks(
47     const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) {
48   IncludeInserter.registerPreprocessor(PP);
49 }
50 
51 void ReplaceRandomShuffleCheck::storeOptions(
52     ClangTidyOptions::OptionMap &Opts) {
53   Options.store(Opts, "IncludeStyle", IncludeInserter.getStyle());
54 }
55 
56 void ReplaceRandomShuffleCheck::check(const MatchFinder::MatchResult &Result) {
57   const auto *MatchedDecl = Result.Nodes.getNodeAs<DeclRefExpr>("name");
58   const auto *MatchedArgumentThree = Result.Nodes.getNodeAs<Expr>("randomFunc");
59   const auto *MatchedCallExpr = Result.Nodes.getNodeAs<CallExpr>("match");
60 
61   if (MatchedCallExpr->getBeginLoc().isMacroID())
62     return;
63 
64   auto Diag = [&] {
65     if (MatchedCallExpr->getNumArgs() == 3) {
66       auto DiagL =
67           diag(MatchedCallExpr->getBeginLoc(),
68                "'std::random_shuffle' has been removed in C++17; use "
69                "'std::shuffle' and an alternative random mechanism instead");
70       DiagL << FixItHint::CreateReplacement(
71           MatchedArgumentThree->getSourceRange(),
72           "std::mt19937(std::random_device()())");
73       return DiagL;
74     }
75     auto DiagL = diag(MatchedCallExpr->getBeginLoc(),
76                       "'std::random_shuffle' has been removed in C++17; use "
77                       "'std::shuffle' instead");
78     DiagL << FixItHint::CreateInsertion(
79         MatchedCallExpr->getRParenLoc(),
80         ", std::mt19937(std::random_device()())");
81     return DiagL;
82   }();
83 
84   std::string NewName = "shuffle";
85   StringRef ContainerText = Lexer::getSourceText(
86       CharSourceRange::getTokenRange(MatchedDecl->getSourceRange()),
87       *Result.SourceManager, getLangOpts());
88   if (ContainerText.startswith("std::"))
89     NewName = "std::" + NewName;
90 
91   Diag << FixItHint::CreateRemoval(MatchedDecl->getSourceRange());
92   Diag << FixItHint::CreateInsertion(MatchedDecl->getBeginLoc(), NewName);
93   Diag << IncludeInserter.createIncludeInsertion(
94       Result.Context->getSourceManager().getFileID(
95           MatchedCallExpr->getBeginLoc()),
96       "<random>");
97 }
98 
99 } // namespace modernize
100 } // namespace tidy
101 } // namespace clang
102