def test_proxy(self):
        """
        Test QgsProviderSublayerProxyModel
        """
        model = QgsProviderSublayerModel()
        proxy = QgsProviderSublayerProxyModel()
        proxy.setSourceModel(model)
        self.assertEqual(model.rowCount(QModelIndex()), 0)
        self.assertEqual(proxy.columnCount(QModelIndex()), 2)
        self.assertEqual(proxy.headerData(0, Qt.Horizontal, Qt.DisplayRole),
                         'Item')
        self.assertEqual(proxy.headerData(0, Qt.Horizontal, Qt.ToolTipRole),
                         'Item')
        self.assertEqual(proxy.headerData(1, Qt.Horizontal, Qt.DisplayRole),
                         'Description')
        self.assertEqual(proxy.headerData(1, Qt.Horizontal, Qt.ToolTipRole),
                         'Description')

        layer1 = QgsProviderSublayerDetails()
        layer1.setType(QgsMapLayerType.RasterLayer)
        layer1.setName('layer 1')
        layer1.setDescription('description 1')
        layer1.setProviderKey('gdal')
        layer1.setUri('uri 1')

        layer2 = QgsProviderSublayerDetails()
        layer2.setType(QgsMapLayerType.VectorLayer)
        layer2.setName('another layer 2')
        layer2.setDescription('description 2')
        layer2.setProviderKey('ogr')
        layer2.setUri('uri 2')
        layer2.setFeatureCount(-1)
        layer2.setWkbType(QgsWkbTypes.LineString)

        model.setSublayerDetails([layer1, layer2])

        item1 = QgsProviderSublayerModel.NonLayerItem()
        item1.setUri('item uri 1')
        item1.setName('item name 1')
        item1.setType('item type 1')
        item1.setDescription('item desc 1')

        model.addNonLayerItem(item1)

        self.assertEqual(proxy.rowCount(QModelIndex()), 3)

        self.assertEqual(proxy.data(proxy.index(0, 0), Qt.DisplayRole),
                         'item name 1')
        self.assertEqual(proxy.data(proxy.index(0, 1), Qt.DisplayRole),
                         'item desc 1')
        self.assertEqual(
            proxy.data(proxy.index(0, 0), QgsProviderSublayerModel.Role.Uri),
            'item uri 1')
        self.assertEqual(
            proxy.data(proxy.index(0, 0), QgsProviderSublayerModel.Role.Name),
            'item name 1')
        self.assertEqual(
            proxy.data(proxy.index(0, 0),
                       QgsProviderSublayerModel.Role.Description),
            'item desc 1')
        self.assertEqual(
            proxy.data(proxy.index(0, 0),
                       QgsProviderSublayerModel.Role.IsNonLayerItem), True)

        self.assertEqual(proxy.data(proxy.index(1, 0), Qt.DisplayRole),
                         'another layer 2')
        self.assertEqual(proxy.data(proxy.index(1, 1), Qt.DisplayRole),
                         'description 2 - LineString (Uncounted)')
        self.assertEqual(
            proxy.data(proxy.index(1, 0),
                       QgsProviderSublayerModel.Role.ProviderKey), 'ogr')
        self.assertEqual(
            proxy.data(proxy.index(1, 0),
                       QgsProviderSublayerModel.Role.LayerType),
            QgsMapLayerType.VectorLayer)
        self.assertEqual(
            proxy.data(proxy.index(1, 0), QgsProviderSublayerModel.Role.Uri),
            'uri 2')
        self.assertEqual(
            proxy.data(proxy.index(1, 0), QgsProviderSublayerModel.Role.Name),
            'another layer 2')
        self.assertEqual(
            proxy.data(proxy.index(1, 0),
                       QgsProviderSublayerModel.Role.Description),
            'description 2')
        self.assertEqual(
            proxy.data(proxy.index(1, 0),
                       QgsProviderSublayerModel.Role.IsNonLayerItem), False)

        self.assertEqual(proxy.data(proxy.index(2, 0), Qt.DisplayRole),
                         'layer 1')
        self.assertEqual(proxy.data(proxy.index(2, 1), Qt.DisplayRole),
                         'description 1')
        self.assertEqual(
            proxy.data(proxy.index(2, 0),
                       QgsProviderSublayerModel.Role.ProviderKey), 'gdal')
        self.assertEqual(
            proxy.data(proxy.index(2, 0),
                       QgsProviderSublayerModel.Role.LayerType),
            QgsMapLayerType.RasterLayer)
        self.assertEqual(
            proxy.data(proxy.index(2, 0), QgsProviderSublayerModel.Role.Uri),
            'uri 1')
        self.assertEqual(
            proxy.data(proxy.index(2, 0), QgsProviderSublayerModel.Role.Name),
            'layer 1')
        self.assertEqual(
            proxy.data(proxy.index(2, 0),
                       QgsProviderSublayerModel.Role.Description),
            'description 1')
        self.assertEqual(
            proxy.data(proxy.index(2, 0),
                       QgsProviderSublayerModel.Role.IsNonLayerItem), False)

        proxy.setFilterString(' 1')
        self.assertEqual(proxy.rowCount(QModelIndex()), 2)
        self.assertEqual(proxy.data(proxy.index(0, 0), Qt.DisplayRole),
                         'item name 1')
        self.assertEqual(proxy.data(proxy.index(1, 0), Qt.DisplayRole),
                         'layer 1')

        proxy.setFilterString(' 2')
        self.assertEqual(proxy.rowCount(QModelIndex()), 1)
        self.assertEqual(proxy.data(proxy.index(0, 0), Qt.DisplayRole),
                         'another layer 2')

        proxy.setFilterString('ITEM')
        self.assertEqual(proxy.rowCount(QModelIndex()), 1)
        self.assertEqual(proxy.data(proxy.index(0, 0), Qt.DisplayRole),
                         'item name 1')

        proxy.setFilterString('')
        self.assertEqual(proxy.rowCount(QModelIndex()), 3)
        self.assertEqual(proxy.data(proxy.index(0, 0), Qt.DisplayRole),
                         'item name 1')
        self.assertEqual(proxy.data(proxy.index(1, 0), Qt.DisplayRole),
                         'another layer 2')
        self.assertEqual(proxy.data(proxy.index(2, 0), Qt.DisplayRole),
                         'layer 1')