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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/.
*/
#include <cassert>
#include <string>
#include <iostream>
#include <fstream>
#include <set>
#include "plugin.hxx"
/**
the comma operator is best used sparingly
*/
namespace {
Stmt const * lookThroughExprWithCleanups(Stmt const * stmt) {
if (auto const e = dyn_cast_or_null<ExprWithCleanups>(stmt)) {
return e->getSubExpr();
}
return stmt;
}
class CommaOperator:
public loplugin::FilteringPlugin<CommaOperator>
{
public:
explicit CommaOperator(loplugin::InstantiationData const & data):
FilteringPlugin(data) {}
virtual void run() override
{
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
}
bool TraverseForStmt(ForStmt * stmt) {
auto const saved1 = ignore1_;
ignore1_ = lookThroughExprWithCleanups(stmt->getInit());
auto const saved2 = ignore2_;
ignore2_ = lookThroughExprWithCleanups(stmt->getInc());
auto const ret = RecursiveASTVisitor::TraverseForStmt(stmt);
ignore1_ = saved1;
ignore2_ = saved2;
return ret;
}
bool TraverseWhileStmt(WhileStmt * stmt) {
auto const saved1 = ignore1_;
ignore1_ = lookThroughExprWithCleanups(stmt->getCond());
auto const ret = RecursiveASTVisitor::TraverseWhileStmt(stmt);
ignore1_ = saved1;
return ret;
}
bool TraverseParenExpr(ParenExpr * expr) {
auto const saved1 = ignore1_;
ignore1_ = expr->getSubExpr();
auto const ret = RecursiveASTVisitor::TraverseParenExpr(expr);
ignore1_ = saved1;
return ret;
}
bool TraverseBinaryOperator(BinaryOperator * expr) {
if (expr->getOpcode() != BO_Comma) {
return RecursiveASTVisitor::TraverseBinaryOperator(expr);
}
if (!WalkUpFromBinaryOperator(expr)) {
return false;
}
auto const saved1 = ignore1_;
ignore1_ = expr->getLHS();
auto const ret = TraverseStmt(expr->getLHS())
&& TraverseStmt(expr->getRHS());
ignore1_ = saved1;
return ret;
}
bool VisitBinaryOperator(const BinaryOperator* );
private:
Stmt const * ignore1_ = nullptr;
Stmt const * ignore2_ = nullptr;
};
bool CommaOperator::VisitBinaryOperator(const BinaryOperator* binaryOp)
{
if (binaryOp->getOpcode() != BO_Comma) {
return true;
}
if (binaryOp == ignore1_ || binaryOp == ignore2_) {
return true;
}
if (ignoreLocation(binaryOp)) {
return true;
}
// Ignore FD_SET expanding to "...} while(0, 0)" in some Microsoft
// winsock2.h (TODO: improve heuristic of determining that the whole
// binaryOp is part of a single macro body expansion):
if (compiler.getSourceManager().isMacroBodyExpansion(
binaryOp->getBeginLoc())
&& compiler.getSourceManager().isMacroBodyExpansion(
binaryOp->getOperatorLoc())
&& compiler.getSourceManager().isMacroBodyExpansion(
binaryOp->getEndLoc())
&& ignoreLocation(
compiler.getSourceManager().getSpellingLoc(
binaryOp->getOperatorLoc())))
{
return true;
}
report(
DiagnosticsEngine::Warning, "comma operator hides code",
binaryOp->getOperatorLoc())
<< binaryOp->getSourceRange();
return true;
}
loplugin::Plugin::Registration< CommaOperator > X("commaoperator", true);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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