def testSignals(self):
QgsProject.instance().clear()
m = QgsMapLayerComboBox()
l1 = QgsVectorLayer(
"Point?crs=EPSG:3111&field=fldtxt:string&field=fldint:integer",
'layer 1', "memory")
QgsProject.instance().addMapLayer(l1)
l2 = QgsVectorLayer(
"Polygon?crs=EPSG:3111&field=fldtxt:string&field=fldint:integer",
'lAyEr 2', "memory")
QgsProject.instance().addMapLayer(l2)
spy = QSignalSpy(m.layerChanged)
m.setLayer(l2)
self.assertEqual(len(spy), 1)
self.assertEqual(m.currentLayer(), l2)
m.setLayer(l1)
self.assertEqual(len(spy), 2)
self.assertEqual(m.currentLayer(), l1)
# no signal if same layer
m.setLayer(l1)
self.assertEqual(len(spy), 2)
m.setAllowEmptyLayer(True)
m.setLayer(None)
self.assertEqual(len(spy), 3)
self.assertIsNone(m.currentLayer())
self.assertFalse(m.currentText())
m.setLayer(None)
self.assertEqual(len(spy), 3)
self.assertIsNone(m.currentLayer())
m.setEditable(True)
m.setCurrentText('aaa')
self.assertIsNone(m.currentLayer())
m.setLayer(l1)
self.assertEqual(len(spy), 4)
self.assertEqual(m.currentLayer(), l1)
