================ @@ -0,0 +1,278 @@ +//===--- MinMaxUseInitializerListCheck.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 "MinMaxUseInitializerListCheck.h" +#include "../utils/ASTUtils.h" +#include "../utils/LexerUtils.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/Frontend/CompilerInstance.h" +#include "clang/Lex/Lexer.h" + +using namespace clang; + +namespace { + +struct FindArgsResult { + const Expr *First; + const Expr *Last; + const Expr *Compare; + SmallVector<const clang::Expr *, 2> Args; +}; + +} // anonymous namespace + +using namespace clang::ast_matchers; + +namespace clang::tidy::modernize { + +static FindArgsResult findArgs(const CallExpr *Call) { + FindArgsResult Result; + Result.First = nullptr; + Result.Last = nullptr; + Result.Compare = nullptr; + + // check if the function has initializer list argument + if (Call->getNumArgs() < 3) { + auto ArgIterator = Call->arguments().begin(); + + const auto *InitListExpr = + dyn_cast<CXXStdInitializerListExpr>(*ArgIterator); + const auto *InitList = + InitListExpr != nullptr + ? dyn_cast<clang::InitListExpr>( + InitListExpr->getSubExpr()->IgnoreImplicit()) + : nullptr; + + if (InitListExpr && InitList) { + Result.Args.insert(Result.Args.begin(), InitList->inits().begin(), + InitList->inits().end()); + Result.First = *ArgIterator; + Result.Last = *ArgIterator; + + // check if there is a comparison argument + std::advance(ArgIterator, 1); + if (ArgIterator != Call->arguments().end()) { + Result.Compare = *ArgIterator; + } + + return Result; + } + // if it has 3 arguments then the last will be the comparison + } else { + Result.Compare = *(std::next(Call->arguments().begin(), 2)); + } + + for (const Expr *Arg : Call->arguments()) { + if (!Result.First) + Result.First = Arg; + + if (Arg == Result.Compare) + continue; + + Result.Args.push_back(Arg); + Result.Last = Arg; + } + + return Result; +} + +static SmallVector<FixItHint> +generateReplacement(const MatchFinder::MatchResult &Match, + const CallExpr *TopCall, const FindArgsResult &Result) { + SmallVector<FixItHint> FixItHints; + + const QualType ResultType = TopCall->getDirectCallee() + ->getReturnType() + .getNonReferenceType() + .getUnqualifiedType() + .getCanonicalType(); + const auto &SourceMngr = *Match.SourceManager; + const auto LanguageOpts = Match.Context->getLangOpts(); + const bool IsInitializerList = Result.First == Result.Last; + + // add { and } if the top call doesn't have an initializer list arg + if (!IsInitializerList) { + FixItHints.push_back( + FixItHint::CreateInsertion(Result.First->getBeginLoc(), "{")); + + if (Result.Compare) + FixItHints.push_back(FixItHint::CreateInsertion( + Lexer::getLocForEndOfToken(Result.Last->getEndLoc(), 0, SourceMngr, + LanguageOpts), + "}")); + else + FixItHints.push_back( + FixItHint::CreateInsertion(TopCall->getEndLoc(), "}")); + } + + for (const Expr *Arg : Result.Args) { + const auto *InnerCall = dyn_cast<CallExpr>(Arg->IgnoreParenImpCasts()); + + // If the argument is not a nested call + if (!InnerCall) { + // check if typecast is required + const QualType ArgType = Arg->IgnoreParenImpCasts() + ->getType() + .getUnqualifiedType() + .getCanonicalType(); + + if (ArgType == ResultType) + continue; + + const StringRef ArgText = Lexer::getSourceText( + CharSourceRange::getTokenRange(Arg->getSourceRange()), SourceMngr, + LanguageOpts); + + Twine Replacement = llvm::Twine("static_cast<") + .concat(ResultType.getAsString(LanguageOpts)) + .concat(">(") + .concat(ArgText) + .concat(")"); + + FixItHints.push_back(FixItHint::CreateReplacement(Arg->getSourceRange(), + Replacement.str())); + + continue; + } + + const auto InnerResult = findArgs(InnerCall); + const auto InnerReplacements = + generateReplacement(Match, InnerCall, InnerResult); + const bool IsInnerInitializerList = InnerResult.First == InnerResult.Last; + + // if the nested call doesn't have arguments skip it + if (!InnerResult.First || !InnerResult.Last) + continue; + + // if the nested call is not the same as the top call + if (InnerCall->getDirectCallee()->getQualifiedNameAsString() != + TopCall->getDirectCallee()->getQualifiedNameAsString()) + continue; + + // if the nested call doesn't have the same compare function + if ((Result.Compare || InnerResult.Compare) && + !utils::areStatementsIdentical(Result.Compare, InnerResult.Compare, + *Match.Context)) + continue; + + // remove the function call + FixItHints.push_back( + FixItHint::CreateRemoval(CharSourceRange::getTokenRange( + InnerCall->getCallee()->getSourceRange()))); + + // remove the parentheses + const auto LParen = utils::lexer::findNextTokenSkippingComments( + InnerCall->getCallee()->getEndLoc(), SourceMngr, LanguageOpts); + FixItHints.push_back( + FixItHint::CreateRemoval(SourceRange(LParen->getLocation()))); + FixItHints.push_back( + FixItHint::CreateRemoval(SourceRange(InnerCall->getRParenLoc()))); + + // if the inner call has an initializer list arg + if (IsInnerInitializerList) { + // remove the initializer list braces + FixItHints.push_back(FixItHint::CreateRemoval( + CharSourceRange::getTokenRange(InnerResult.First->getBeginLoc()))); + FixItHints.push_back(FixItHint::CreateRemoval( + CharSourceRange::getTokenRange(InnerResult.First->getEndLoc()))); + } + + FixItHints.insert(FixItHints.end(), + // ignore { and } insertions for the inner call if it does + // not have an initializer list arg + InnerReplacements.begin() + (!IsInnerInitializerList) * 2, + InnerReplacements.end()); + + if (InnerResult.Compare) { + // find the comma after the value arguments + const auto Comma = utils::lexer::findNextTokenSkippingComments( + InnerResult.Last->getEndLoc(), SourceMngr, LanguageOpts); + + // if there are comments between the comma and the comparison + if (utils::lexer::getPreviousToken(InnerResult.Compare->getExprLoc(), + SourceMngr, LanguageOpts, false) + .getLocation() != Comma->getLocation()) { + // remove the comma and the comparison + FixItHints.push_back( + FixItHint::CreateRemoval(SourceRange(Comma->getLocation()))); + + FixItHints.push_back( + FixItHint::CreateRemoval(CharSourceRange::getTokenRange( + InnerResult.Compare->getSourceRange()))); + } else + // remove everything after the last argument + FixItHints.push_back( + FixItHint::CreateRemoval(CharSourceRange::getTokenRange( + Comma->getLocation(), InnerResult.Compare->getEndLoc()))); + } + } + + return FixItHints; +} + +MinMaxUseInitializerListCheck::MinMaxUseInitializerListCheck( + StringRef Name, ClangTidyContext *Context) + : ClangTidyCheck(Name, Context), + Inserter(Options.getLocalOrGlobal("IncludeStyle", + utils::IncludeSorter::IS_LLVM), + areDiagsSelfContained()) {} + +void MinMaxUseInitializerListCheck::storeOptions( + ClangTidyOptions::OptionMap &Opts) { + Options.store(Opts, "IncludeStyle", Inserter.getStyle()); +} + +void MinMaxUseInitializerListCheck::registerMatchers(MatchFinder *Finder) { + auto CreateMatcher = [](const StringRef FunctionName) { + auto FuncDecl = functionDecl(hasName(FunctionName)); + auto Expression = callExpr(callee(FuncDecl)); + + return callExpr(callee(FuncDecl), + anyOf(hasArgument(0, Expression), + hasArgument(1, Expression), + hasArgument(0, cxxStdInitializerListExpr())), + unless(hasParent(Expression))) + .bind("topCall"); + }; + + Finder->addMatcher(CreateMatcher("::std::max"), this); + Finder->addMatcher(CreateMatcher("::std::min"), this); +} + +void MinMaxUseInitializerListCheck::registerPPCallbacks( + const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) { + Inserter.registerPreprocessor(PP); +} + +void MinMaxUseInitializerListCheck::check( + const MatchFinder::MatchResult &Match) { + + const auto *TopCall = Match.Nodes.getNodeAs<CallExpr>("topCall"); + + const FindArgsResult Result = findArgs(TopCall); + const SmallVector<FixItHint> Replacement = + generateReplacement(Match, TopCall, Result); + + if (Replacement.size() <= 2) { + return; + } ---------------- 5chmidti wrote:
It's not immediately clear why `<= 2` is needed, please add a small comment. Also, a single statement if-branch should not have braces. https://github.com/llvm/llvm-project/pull/85572 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
