summaryrefslogtreecommitdiffstats
path: root/tests/auto/corelib/tools/qscopeguard/tst_qscopeguard.cpp
blob: b7c2b952e2d889e28f072c6694a944f006e062f5 (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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
// Copyright (C) 2018 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Sérgio Martins <sergio.martins@kdab.com>
// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only

#include <QTest>
#include <QtCore/QScopeGuard>

#include <optional>

/*!
 \class tst_QScopeGuard
 \internal
 \since 5.11
 \brief Tests class QScopeGuard and function qScopeGuard

 */
class tst_QScopeGuard : public QObject
{
    Q_OBJECT

private Q_SLOTS:
    void construction();
    void constructionFromLvalue();
    void constructionFromRvalue();
    void optionalGuard();
    void leavingScope();
    void exceptions();
};

void func()
{
}

int intFunc()
{
    return 0;
}

[[nodiscard]] int noDiscardFunc()
{
    return 0;
}

struct Callable
{
    Callable() { }
    Callable(const Callable &other)
    {
        Q_UNUSED(other);
        ++copied;
    }
    Callable(Callable &&other)
    {
        Q_UNUSED(other);
        ++moved;
    }
    void operator()() { }

    static int copied;
    static int moved;
    static void resetCounts()
    {
        copied = 0;
        moved = 0;
    }
};

int Callable::copied = 0;
int Callable::moved = 0;

static int s_globalState = 0;

void tst_QScopeGuard::construction()
{
    QScopeGuard fromLambda([] { });
    QScopeGuard fromFunction(func);
    QScopeGuard fromFunctionPointer(&func);
    QScopeGuard fromNonVoidFunction(intFunc);
    QScopeGuard fromNoDiscardFunction(noDiscardFunc);
#ifndef __apple_build_version__
    QScopeGuard fromStdFunction{std::function<void()>(func)};
    std::function<void()> stdFunction(func);
    QScopeGuard fromNamedStdFunction(stdFunction);
#endif
}

void tst_QScopeGuard::constructionFromLvalue()
{
    Callable::resetCounts();
    {
        Callable callable;
        QScopeGuard guard(callable);
    }
    QCOMPARE(Callable::copied, 1);
    QCOMPARE(Callable::moved, 0);
    Callable::resetCounts();
    {
        Callable callable;
        auto guard = qScopeGuard(callable);
    }
    QCOMPARE(Callable::copied, 1);
    QCOMPARE(Callable::moved, 0);
}

void tst_QScopeGuard::constructionFromRvalue()
{
    Callable::resetCounts();
    {
        Callable callable;
        QScopeGuard guard(std::move(callable));
    }
    QCOMPARE(Callable::copied, 0);
    QCOMPARE(Callable::moved, 1);
    Callable::resetCounts();
    {
        Callable callable;
        auto guard = qScopeGuard(std::move(callable));
    }
    QCOMPARE(Callable::copied, 0);
    QCOMPARE(Callable::moved, 1);
}

void tst_QScopeGuard::optionalGuard()
{
    int i = 0;
    auto lambda = [&] { ++i; };
    std::optional sg = false ? std::optional{qScopeGuard(lambda)} : std::nullopt;
    QVERIFY(!sg);
    QCOMPARE(i, 0);
    sg.emplace(qScopeGuard(lambda));
    QVERIFY(sg);
    sg->dismiss();
    sg.reset();
    QCOMPARE(i, 0);
    sg.emplace(qScopeGuard(lambda));
    QCOMPARE(i, 0);
    sg.reset();
    QCOMPARE(i, 1);
}

void tst_QScopeGuard::leavingScope()
{
    auto cleanup = qScopeGuard([] { s_globalState++; QCOMPARE(s_globalState, 3); });
    QCOMPARE(s_globalState, 0);

    {
        auto cleanup = qScopeGuard([] { s_globalState++; });
        QCOMPARE(s_globalState, 0);
    }

    QCOMPARE(s_globalState, 1);
    s_globalState++;
}

void tst_QScopeGuard::exceptions()
{
    s_globalState = 0;
    bool caught = false;
    QT_TRY
    {
        auto cleanup = qScopeGuard([] { s_globalState++; });
        QT_THROW(std::bad_alloc()); //if Qt compiled without exceptions this is noop
        s_globalState = 100;
    }
    QT_CATCH(...)
    {
        caught = true;
        QCOMPARE(s_globalState, 1);
    }

    QVERIFY((caught && s_globalState == 1) || (!caught && s_globalState == 101));

}

QTEST_MAIN(tst_QScopeGuard)
#include "tst_qscopeguard.moc"