clang-tools 10.0.0

ReturnBracedInitListCheck.cpp
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1 //===--- ReturnBracedInitListCheck.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 "ReturnBracedInitListCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 #include "clang/Lex/Lexer.h"
13 #include "clang/Tooling/FixIt.h"
14
15 using namespace clang::ast_matchers;
16
17 namespace clang {
18 namespace tidy {
19 namespace modernize {
20
21 void ReturnBracedInitListCheck::registerMatchers(MatchFinder *Finder) {
22 // Only register the matchers for C++.
23 if (!getLangOpts().CPlusPlus11)
24 return;
25
26 // Skip list initialization and constructors with an initializer list.
27 auto ConstructExpr =
28 cxxConstructExpr(
29 unless(anyOf(hasDeclaration(cxxConstructorDecl(isExplicit())),
30 isListInitialization(), hasDescendant(initListExpr()),
31 isInTemplateInstantiation())))
32 .bind("ctor");
33
34 auto CtorAsArgument = materializeTemporaryExpr(anyOf(
35 has(ConstructExpr), has(cxxFunctionalCastExpr(has(ConstructExpr)))));
36
37 Finder->addMatcher(
38 functionDecl(isDefinition(), // Declarations don't have return statements.
39 returns(unless(anyOf(builtinType(), autoType()))),
40 hasDescendant(returnStmt(hasReturnValue(
41 has(cxxConstructExpr(has(CtorAsArgument)))))))
42 .bind("fn"),
43 this);
44 }
45
46 void ReturnBracedInitListCheck::check(const MatchFinder::MatchResult &Result) {
47 const auto *MatchedFunctionDecl = Result.Nodes.getNodeAs<FunctionDecl>("fn");
48 const auto *MatchedConstructExpr =
49 Result.Nodes.getNodeAs<CXXConstructExpr>("ctor");
50
51 // Don't make replacements in macro.
52 SourceLocation Loc = MatchedConstructExpr->getExprLoc();
53 if (Loc.isMacroID())
54 return;
55
56 // Make sure that the return type matches the constructed type.
57 const QualType ReturnType =
58 MatchedFunctionDecl->getReturnType().getCanonicalType();
59 const QualType ConstructType =
60 MatchedConstructExpr->getType().getCanonicalType();
61 if (ReturnType != ConstructType)
62 return;
63
64 auto Diag = diag(Loc, "avoid repeating the return type from the "
65 "declaration; use a braced initializer list instead");
66
67 const SourceRange CallParensRange =
68 MatchedConstructExpr->getParenOrBraceRange();
69
70 // Make sure there is an explicit constructor call.
71 if (CallParensRange.isInvalid())
72 return;
73
74 // Make sure that the ctor arguments match the declaration.
75 for (unsigned I = 0, NumParams = MatchedConstructExpr->getNumArgs();
76 I < NumParams; ++I) {
77 if (const auto *VD = dyn_cast<VarDecl>(
78 MatchedConstructExpr->getConstructor()->getParamDecl(I))) {
79 if (MatchedConstructExpr->getArg(I)->getType().getCanonicalType() !=
80 VD->getType().getCanonicalType())
81 return;
82 }
83 }
84
85 // Range for constructor name and opening brace.
86 CharSourceRange CtorCallSourceRange = CharSourceRange::getTokenRange(
87 Loc, CallParensRange.getBegin().getLocWithOffset(-1));
88
89 Diag << FixItHint::CreateRemoval(CtorCallSourceRange)
90 << FixItHint::CreateReplacement(CallParensRange.getBegin(), "{")
91 << FixItHint::CreateReplacement(CallParensRange.getEnd(), "}");
92 }
93
94 } // namespace modernize
95 } // namespace tidy
96 } // namespace clang
Loc
SourceLocation Loc
&#39;#&#39; location in the include directive
Definition: IncludeOrderCheck.cpp:37
clang::ast_matchers
Definition: AbseilMatcher.h:14
clang::clangd::getTokenRange
llvm::Optional< Range > getTokenRange(const SourceManager &SM, const LangOptions &LangOpts, SourceLocation TokLoc)
Returns the taken range at TokLoc.
Definition: SourceCode.cpp:227
ReturnType
std::string ReturnType
Definition: CodeComplete.cpp:395
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ApplyReplacements.h:27
ReturnBracedInitListCheck.h