1 //===--- UseToStringCheck.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 "UseToStringCheck.h"
10 
11 using namespace clang::ast_matchers;
12 
13 namespace clang {
14 namespace tidy {
15 namespace boost {
16 
17 namespace {
AST_MATCHER(Type,isStrictlyInteger)18 AST_MATCHER(Type, isStrictlyInteger) {
19   return Node.isIntegerType() && !Node.isAnyCharacterType() &&
20          !Node.isBooleanType();
21 }
22 } // namespace
23 
registerMatchers(MatchFinder * Finder)24 void UseToStringCheck::registerMatchers(MatchFinder *Finder) {
25   Finder->addMatcher(
26       callExpr(
27           hasDeclaration(functionDecl(
28               returns(hasDeclaration(classTemplateSpecializationDecl(
29                   hasName("std::basic_string"),
30                   hasTemplateArgument(0,
31                                       templateArgument().bind("char_type"))))),
32               hasName("boost::lexical_cast"),
33               hasParameter(0, hasType(qualType(has(substTemplateTypeParmType(
34                                   isStrictlyInteger()))))))),
35           argumentCountIs(1), unless(isInTemplateInstantiation()))
36           .bind("to_string"),
37       this);
38 }
39 
check(const MatchFinder::MatchResult & Result)40 void UseToStringCheck::check(const MatchFinder::MatchResult &Result) {
41   const auto *Call = Result.Nodes.getNodeAs<CallExpr>("to_string");
42   auto CharType =
43       Result.Nodes.getNodeAs<TemplateArgument>("char_type")->getAsType();
44 
45   StringRef StringType;
46   if (CharType->isSpecificBuiltinType(BuiltinType::Char_S) ||
47       CharType->isSpecificBuiltinType(BuiltinType::Char_U))
48     StringType = "string";
49   else if (CharType->isSpecificBuiltinType(BuiltinType::WChar_S) ||
50            CharType->isSpecificBuiltinType(BuiltinType::WChar_U))
51     StringType = "wstring";
52   else
53     return;
54 
55   auto Loc = Call->getBeginLoc();
56   auto Diag =
57       diag(Loc, "use std::to_%0 instead of boost::lexical_cast<std::%0>")
58       << StringType;
59 
60   if (Loc.isMacroID())
61     return;
62 
63   Diag << FixItHint::CreateReplacement(
64       CharSourceRange::getCharRange(Call->getBeginLoc(),
65                                     Call->getArg(0)->getBeginLoc()),
66       (llvm::Twine("std::to_") + StringType + "(").str());
67 }
68 
69 } // namespace boost
70 } // namespace tidy
71 } // namespace clang
72