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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef LO_CLANG_SHARED_PLUGINS
#include <memory>
#include <cassert>
#include <string>
#include <iostream>
#include <fstream>
#include <set>
#include "check.hxx"
#include "plugin.hxx"
/**
Look for places we are using map[idx] in a bool context, which allocates an entry in the map, which is sometimes a side-effect we don't want.
*/
namespace
{
class MapIndex : public loplugin::FilteringPlugin<MapIndex>
{
public:
explicit MapIndex(loplugin::InstantiationData const& data)
: FilteringPlugin(data)
{
}
virtual void run() override
{
if (preRun())
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
}
bool VisitImplicitCastExpr(const ImplicitCastExpr*);
bool VisitMemberExpr(const MemberExpr*);
};
bool MapIndex::VisitMemberExpr(const MemberExpr* memberExpr)
{
if (ignoreLocation(memberExpr))
return true;
// operator bool conversion
auto conversionDecl = dyn_cast<CXXConversionDecl>(memberExpr->getMemberDecl());
if (!conversionDecl || !conversionDecl->getConversionType()->isBooleanType())
return true;
auto operatorCall = dyn_cast<CXXOperatorCallExpr>(memberExpr->getBase()->IgnoreCasts());
if (!operatorCall)
return true;
if (operatorCall->getOperator() != OverloadedOperatorKind::OO_Subscript)
return true;
auto tc = loplugin::TypeCheck(operatorCall->getArg(0)->getType());
if (!tc.Class("map") && !tc.Class("unordered_map"))
return true;
report(DiagnosticsEngine::Warning,
"will create an empty entry in the map, you sure about that, rather use count()1",
operatorCall->getExprLoc());
return true;
}
bool MapIndex::VisitImplicitCastExpr(const ImplicitCastExpr* implicitCastExpr)
{
if (ignoreLocation(implicitCastExpr))
{
return true;
}
// first cast is some kind of "ToBoolean" cast
auto ck = implicitCastExpr->getCastKind();
if (ck != CK_MemberPointerToBoolean && ck != CK_PointerToBoolean && ck != CK_IntegralToBoolean
&& ck != CK_FloatingToBoolean && ck != CK_FloatingComplexToBoolean
&& ck != CK_IntegralComplexToBoolean)
return true;
// second cast is LValueToRValue
implicitCastExpr = dyn_cast<ImplicitCastExpr>(implicitCastExpr->getSubExpr());
if (!implicitCastExpr)
return true;
if (implicitCastExpr->getCastKind() != CK_LValueToRValue)
return true;
auto operatorCall = dyn_cast<CXXOperatorCallExpr>(implicitCastExpr->getSubExpr());
if (!operatorCall)
return true;
if (operatorCall->getOperator() != OverloadedOperatorKind::OO_Subscript)
return true;
auto tc = loplugin::TypeCheck(operatorCall->getArg(0)->getType());
if (!tc.Class("map") && !tc.Class("unordered_map"))
return true;
report(DiagnosticsEngine::Warning,
"will create an empty entry in the map, you sure about that, rather use count()2",
implicitCastExpr->getExprLoc());
return true;
}
loplugin::Plugin::Registration<MapIndex> mapindex("mapindex");
} // namespace
#endif // LO_CLANG_SHARED_PLUGINS
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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