fix: tidy up metadata form parentage

bec_widgets/widgets/editors/scan_metadata/scan_metadata.py

@@ -39,22 +39,26 @@ class ScanMetadata(PydanticModelForm):
 
         # self.populate() gets called in super().__init__
         # so make sure self._additional_metadata exists
-        self._additional_md_box = ExpandableGroupFrame(
-            parent, "Additional metadata", expanded=False
-        )
+        self._scan_name = scan_name or ""
+        self._md_schema = get_metadata_schema_for_scan(self._scan_name)
+        super().__init__(parent=parent, data_model=self._md_schema, client=client, **kwargs)
+
+        self._additional_md_box = ExpandableGroupFrame(self, "Additional metadata", expanded=False)
         self._additional_md_box_layout = QHBoxLayout()
         self._additional_md_box.set_layout(self._additional_md_box_layout)
 
-        self._additional_metadata = DictBackedTable(parent, initial_extras or [])
-        self._scan_name = scan_name or ""
-        self._md_schema = get_metadata_schema_for_scan(self._scan_name)
+        self._additional_metadata = DictBackedTable(self, initial_extras or [])
         self._additional_metadata.data_changed.connect(self.validate_form)
 
-        super().__init__(parent=parent, data_model=self._md_schema, client=client, **kwargs)
-
         self._layout.addWidget(self._additional_md_box)
         self._additional_md_box_layout.addWidget(self._additional_metadata)
 
+        self.populate()
+        self.enabled = self._enabled
+
+    def _post_init(self):
+        return
+
     @SafeSlot(str)
     def update_with_new_scan(self, scan_name: str):
         self.set_schema_from_scan(scan_name)

tests/end-2-end/test_dockarea_menu.py

@@ -0,0 +1,42 @@
+import pytest
+from qtpy.QtCore import Qt
+
+from bec_widgets.widgets.containers.dock.dock_area import BECDockArea
+
+
+@pytest.fixture
+def dock_area(qtbot):
+
+    dock = BECDockArea()
+    qtbot.addWidget(dock)
+    qtbot.waitExposed(dock)
+    dock.show()
+    qtbot.wait(500)
+
+    yield dock
+
+    dock.remove()
+    dock.deleteLater()
+
+
+def test_sequence_of_add_and_remove(qtbot, dock_area):
+
+    add_sc_action = dock_area.toolbar.widgets["menu_devices"].widgets["scan_control"]
+    add_pb_action = dock_area.toolbar.widgets["menu_devices"].widgets["positioner_box"]
+
+    add_pb_action.trigger()
+    qtbot.wait(1000)
+
+    add_sc_action.trigger()
+    qtbot.wait(1000)
+
+    assert all(w in dock_area.panels for w in ["positioner_box_0", "scan_control_0"])
+
+    dock_area.panels["positioner_box_0"].remove()
+    qtbot.wait(1000)
+
+    dock_area.panels["scan_control_0"].remove()
+    qtbot.wait(1000)
+
+    add_pb_action.trigger()
+    qtbot.wait(1000)