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 {
18 AST_MATCHER(Type, isStrictlyInteger) {
19   return Node.isIntegerType() && !Node.isAnyCharacterType() &&
20          !Node.isBooleanType();
21 }
22 } // namespace
23 
24 void UseToStringCheck::registerMatchers(MatchFinder *Finder) {
25   if (!getLangOpts().CPlusPlus)
26     return;
27 
28   Finder->addMatcher(
29       callExpr(
30           hasDeclaration(functionDecl(
31               returns(hasDeclaration(classTemplateSpecializationDecl(
32                   hasName("std::basic_string"),
33                   hasTemplateArgument(0,
34                                       templateArgument().bind("char_type"))))),
35               hasName("boost::lexical_cast"),
36               hasParameter(0, hasType(qualType(has(substTemplateTypeParmType(
37                                   isStrictlyInteger()))))))),
38           argumentCountIs(1), unless(isInTemplateInstantiation()))
39           .bind("to_string"),
40       this);
41 }
42 
43 void UseToStringCheck::check(const MatchFinder::MatchResult &Result) {
44   const auto *Call = Result.Nodes.getNodeAs<CallExpr>("to_string");
45   auto CharType =
46       Result.Nodes.getNodeAs<TemplateArgument>("char_type")->getAsType();
47 
48   StringRef StringType;
49   if (CharType->isSpecificBuiltinType(BuiltinType::Char_S) ||
50       CharType->isSpecificBuiltinType(BuiltinType::Char_U))
51     StringType = "string";
52   else if (CharType->isSpecificBuiltinType(BuiltinType::WChar_S) ||
53            CharType->isSpecificBuiltinType(BuiltinType::WChar_U))
54     StringType = "wstring";
55   else
56     return;
57 
58   auto Loc = Call->getBeginLoc();
59   auto Diag =
60       diag(Loc, "use std::to_%0 instead of boost::lexical_cast<std::%0>")
61       << StringType;
62 
63   if (Loc.isMacroID())
64     return;
65 
66   Diag << FixItHint::CreateReplacement(
67       CharSourceRange::getCharRange(Call->getBeginLoc(),
68                                     Call->getArg(0)->getBeginLoc()),
69       (llvm::Twine("std::to_") + StringType + "(").str());
70 }
71 
72 } // namespace boost
73 } // namespace tidy
74 } // namespace clang
75