| //===--- ShrinkToFitCheck.cpp - clang-tidy---------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "ShrinkToFitCheck.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/ASTMatchers/ASTMatchFinder.h" |
| #include "clang/Lex/Lexer.h" |
| #include "llvm/ADT/StringRef.h" |
| |
| using namespace clang::ast_matchers; |
| |
| namespace clang::tidy::modernize { |
| |
| void ShrinkToFitCheck::registerMatchers(MatchFinder *Finder) { |
| // Swap as a function need not to be considered, because rvalue can not |
| // be bound to a non-const reference. |
| const auto ShrinkableExpr = mapAnyOf(memberExpr, declRefExpr); |
| const auto Shrinkable = |
| ShrinkableExpr.with(hasDeclaration(valueDecl().bind("ContainerDecl"))); |
| const auto BoundShrinkable = ShrinkableExpr.with( |
| hasDeclaration(valueDecl(equalsBoundNode("ContainerDecl")))); |
| |
| Finder->addMatcher( |
| cxxMemberCallExpr( |
| callee(cxxMethodDecl(hasName("swap"))), |
| hasArgument( |
| 0, anyOf(Shrinkable, unaryOperator(hasUnaryOperand(Shrinkable)))), |
| on(cxxConstructExpr(hasArgument( |
| 0, |
| expr(anyOf(BoundShrinkable, |
| unaryOperator(hasUnaryOperand(BoundShrinkable))), |
| hasType(hasCanonicalType(hasDeclaration(namedDecl(hasAnyName( |
| "std::basic_string", "std::deque", "std::vector")))))) |
| .bind("ContainerToShrink"))))) |
| .bind("CopyAndSwapTrick"), |
| this); |
| } |
| |
| void ShrinkToFitCheck::check(const MatchFinder::MatchResult &Result) { |
| const auto *MemberCall = |
| Result.Nodes.getNodeAs<CXXMemberCallExpr>("CopyAndSwapTrick"); |
| const auto *Container = Result.Nodes.getNodeAs<Expr>("ContainerToShrink"); |
| FixItHint Hint; |
| |
| if (!MemberCall->getBeginLoc().isMacroID()) { |
| const LangOptions &Opts = getLangOpts(); |
| std::string ReplacementText; |
| if (const auto *UnaryOp = llvm::dyn_cast<UnaryOperator>(Container)) { |
| ReplacementText = std::string( |
| Lexer::getSourceText(CharSourceRange::getTokenRange( |
| UnaryOp->getSubExpr()->getSourceRange()), |
| *Result.SourceManager, Opts)); |
| ReplacementText += "->shrink_to_fit()"; |
| } else { |
| ReplacementText = std::string(Lexer::getSourceText( |
| CharSourceRange::getTokenRange(Container->getSourceRange()), |
| *Result.SourceManager, Opts)); |
| ReplacementText += ".shrink_to_fit()"; |
| } |
| |
| Hint = FixItHint::CreateReplacement(MemberCall->getSourceRange(), |
| ReplacementText); |
| } |
| |
| diag(MemberCall->getBeginLoc(), "the shrink_to_fit method should be used " |
| "to reduce the capacity of a shrinkable " |
| "container") |
| << Hint; |
| } |
| |
| } // namespace clang::tidy::modernize |