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  1. Qt
  2. QTBUG-40363

Use of QVariant conversions cause asymmetric and intransitive operator==()

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    • 294e65f8092dd5b624740ee39d52979c7ca6f387

      The use of QVariant conversions results in asymmetric and intransitive equality comparison, making it unsuitable for use in containers that require EqualityComparable. It also leads to unexpected behaviour in QMap (content depends on insertion order):

      int main()
{
    QVariant v1(97);
    QVariant v2(QUrl("a"));
    QVariant v3(QChar('a'));
 
    QMap<QVariant, int> s1;
    s1.insert(v1, 1);
    s1.insert(v2, 1);
    s1.insert(v3, 1);
 
    QMap<QVariant, int> s2;
    s2.insert(v3, 1);
    s2.insert(v2, 1);
    s2.insert(v1, 1);
 
    assert(s1.size() == 2);
    assert(s2.size() == 1);
 
    return 0;
}

        For Gerrit Dashboard: QTBUG-40363
        # Subject Branch Project Status CR V
        92864,5 QVariant::compare shouldn't return match when QVariant::cmp does not 5.4 qt/qtbase Status: MERGED +2 0

            allan.jensen Allan Sandfeld Jensen
            hjk hjk
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            Watchers:
            6 Start watching this issue

              Created:
              Updated:
              Resolved:

                There are no open Gerrit changes