12ae2e8075
QDBusSignature holds a D-Bus value of type SIGNATURE, which is zero or more signatures, not one or more. This changes the default constructor to create a valid signature, which we denote by not being a null QString. That means we need to use something other than the default constructor in our tests for attempting to pass invalid signatures. [ChangeLog][QtDBus][QDBusSignature] Fixed a bug that caused the class not to accept an empty string as a valid D-Bus SIGNATURE value. Fixes: QTBUG-124919 Pick-to: 6.5 Change-Id: I262c3499666e4f4fbcfbfffd17cb3793dcf2eae3 Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io> (cherry picked from commit ed6d1fa71a79a70b7e6a20fbbc737ed9f6c287b1) Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>