QUrl's operator==() is taking bygone data into account

The comparesEqual() function checks sectionIsPresent only for comparing that it's the same in lhs and rhs, not for whether it should compare a given section at all. So if a section contains stale data, such as other in QTBUG-134896, and setUrl() with a valid URL is called, then the resulting object will compare not equal to a QUrl object that was constructed with the same string passed to its ctor:

QUrl url1;
url1.setFragment("meep"); // see QTBUG-134896
url1.setUrl("https://www.qt-project.org"); // does not overwrite d->fragment
QUrl url2("https://www.qt-project.org");
QCOMPARE_EQ(url1, url2); // prints the same string, but claims they're different

QUrl url1("https://www.qt-project.org);