aboutsummaryrefslogtreecommitdiffstats
path: root/src/checks/requiredresults.cpp
blob: e9a0f09b602fa4f254cc54b4e57cb242c85abcce (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/*
   This file is part of the clazy static checker.

  Copyright (C) 2015 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com
  Author: Sérgio Martins <sergio.martins@kdab.com>

  Copyright (C) 2015 Sergio Martins <smartins@kde.org>

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either
  version 2 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Library General Public License for more details.

  You should have received a copy of the GNU Library General Public License
  along with this library; see the file COPYING.LIB.  If not, write to
  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  Boston, MA 02110-1301, USA.
*/

#include "requiredresults.h"
#include "Utils.h"


#include <clang/AST/DeclCXX.h>
#include <clang/AST/Expr.h>
#include <clang/AST/ExprCXX.h>

using namespace clang;

RequiredResults::RequiredResults(const std::string &name, ClazyContext *context)
    : CheckBase(name, context)
{
}

bool RequiredResults::shouldIgnoreMethod(const StringRef &qualifiedName)
{
    static const std::vector<StringRef> files = {
        "QDir::mkdir",
        "QDir::rmdir",
        "QDir::mkpath",
        "QDBusConnection::send",

        "QRegExp::indexIn",
        "QRegExp::exactMatch",
        "QQmlProperty::write",
        "QQmlProperty::reset",
        "QWidget::winId",
        "QtWaylandClient::QWaylandEglWindow::contentFBO",
        "ProString::updatedHash",

        // kdepim
        "KCalCore::Incidence::recurrence",
        "KCalCore::RecurrenceRule::Private::buildCache",
        "KAlarmCal::KAEvent::updateKCalEvent",
        "Akonadi::Server::Collection::clearMimeTypes",
        "Akonadi::Server::Collection::addMimeType",
        "Akonadi::Server::PimItem::addFlag",
        "Akonadi::Server::PimItem::addTag",

        // kf5 libs
        "KateVi::Command::execute",
        "KArchiveDirectory::copyTo",
        "KBookmarkManager::saveAs",
        "KBookmarkManager::save",
        "KLineEditPrivate::copySqueezedText",
        "KJS::UString::Rep::hash",
        "KCModuleProxy::realModule",
        "KCategorizedView::visualRect",
        "KateLineLayout::textLine",
        "DOM::HTMLCollectionImpl::firstItem",
        "DOM::HTMLCollectionImpl::nextItem",
        "DOM::HTMLCollectionImpl::firstItem",
        "ImapResourceBase::settings"
    };

    return clazy::contains(files, qualifiedName);
}

void RequiredResults::VisitStmt(clang::Stmt *stm)
{
    auto compound = dyn_cast<CompoundStmt>(stm);
    if (!compound)
        return;

    for (auto child : compound->children()) {
        auto callExpr = dyn_cast<CXXMemberCallExpr>(child);
        if (!callExpr)
            continue;

        CXXMethodDecl *methodDecl = callExpr->getMethodDecl();
        if (!methodDecl || !methodDecl->isConst())
            continue;

        std::string methodName = methodDecl->getQualifiedNameAsString();
        if (shouldIgnoreMethod(StringRef(methodName.c_str()))) // Filter out some false positives
            continue;

        QualType qt = methodDecl->getReturnType();
        const Type *type = qt.getTypePtrOrNull();
        if (!type || type->isVoidType())
            continue;

        // Bail-out if any parameter is a non-const-ref or pointer bool bailout = false;
        bool bailout = false;
        for (auto paramVarDecl : Utils::functionParameters(methodDecl)) {
            QualType qt = paramVarDecl->getType();
            const Type *type = qt.getTypePtrOrNull();
            if (!type || type->isPointerType()) {
                bailout = true;
                break;
            }

            // qt.isConstQualified() not working !? TODO: Replace this string parsing when I figure it out
            if (type->isReferenceType() && !clazy::contains(qt.getAsString(), "const ")) {
                bailout = true;
                break;
            }
        }

        if (!bailout) {
            std::string error = std::string("Unused result of const member (") + methodName + ')';
            emitWarning(getLocStart(callExpr), error.c_str());
        }
    }
}