tests: add test for rpcrefernce on rpcbase object

tests/unit_tests/test_rpc_base.py

@@ -0,0 +1,28 @@
+import pytest
+
+from bec_widgets.cli.rpc.rpc_base import DeletedWidgetError, RPCBase, RPCReference
+
+
+@pytest.fixture
+def rpc_base():
+    yield RPCBase(gui_id="rpc_base_test", name="test")
+
+
+def test_rpc_base(rpc_base):
+    """Test registry and reference creation"""
+    registry = {rpc_base._gui_id: rpc_base}
+    ref = RPCReference(registry, rpc_base._gui_id)
+
+    assert ref._gui_id == rpc_base._gui_id
+    assert ref.widget_name == rpc_base.widget_name
+    assert ref.__str__() == rpc_base.__str__()
+    assert ref.__repr__() == rpc_base.__repr__()
+
+    # Remove object from registry
+    registry.pop(rpc_base._gui_id)
+
+    assert ref.__str__() == f"<Deleted widget with gui_id {rpc_base._gui_id}>"
+    assert ref.__repr__() == f"<Deleted widget with gui_id {rpc_base._gui_id}>"
+
+    with pytest.raises(DeletedWidgetError):
+        ref.widget_name  # Object no longer referenced in registry