Ensure children can be updated if not added initially

src/panel_reactflow/base.py

@@ -1366,18 +1366,15 @@ def _get_children(self, data_model, doc, root, parent, comm) -> tuple[dict[str,
 
         children: dict[str, list[UIElement] | UIElement | None] = {}
         old_models: list[UIElement] = []
-        if views:
-            views, view_models = self._get_child_model(views, doc, root, parent, comm)
-            children["_views"] = views
-            old_models += view_models
-        if node_editors:
-            editor_models, editor_old = self._get_child_model(node_editors, doc, root, parent, comm)
-            children["_node_editor_views"] = editor_models
-            old_models += editor_old
-        if edge_editors:
-            edge_models, edge_old = self._get_child_model(edge_editors, doc, root, parent, comm)
-            children["_edge_editor_views"] = edge_models
-            old_models += edge_old
+        views, view_models = self._get_child_model(views, doc, root, parent, comm)
+        children["_views"] = views
+        old_models += view_models
+        editor_models, editor_old = self._get_child_model(node_editors, doc, root, parent, comm)
+        children["_node_editor_views"] = editor_models
+        old_models += editor_old
+        edge_models, edge_old = self._get_child_model(edge_editors, doc, root, parent, comm)
+        children["_edge_editor_views"] = edge_models
+        old_models += edge_old
         for name in ("top_panel", "bottom_panel", "left_panel", "right_panel"):
             panels = list(getattr(self, name, []) or [])
             if panels:

tests/test_api.py

@@ -147,62 +147,6 @@ def test_reactflow_add_node_with_view() -> None:
     assert events[-1]["type"] == "node_added"
 
 
-def test_view_idx_updates_on_remove_node(document, comm) -> None:
-    flow = ReactFlow()
-    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "data": {}, "view": pn.pane.Markdown("A")})
-    flow.add_node({"id": "n2", "position": {"x": 1, "y": 1}, "data": {}, "view": pn.pane.Markdown("B")})
-    flow.add_node({"id": "n3", "position": {"x": 2, "y": 2}, "data": {}})
-
-    model = flow.get_root(document, comm=comm)
-
-    flow.remove_node("n1")
-
-    remaining = {node["id"]: node for node in model.data.nodes}
-    assert remaining["n2"]["data"]["view_idx"] == 0
-    assert remaining["n3"]["data"].get("view_idx") is None
-
-
-def test_reactflow_add_node_with_viewer(document, comm) -> None:
-    """Test that Viewer objects with __panel__() method work as node views."""
-
-    class MyViewer(pn.viewable.Viewer):
-        def __panel__(self):
-            return pn.pane.Markdown("Hello from Viewer!")
-
-    flow = ReactFlow()
-    my_viewer = MyViewer()
-    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "label": "Viewer Node", "data": {}, "view": my_viewer})
-
-    # This should not raise AttributeError about '_models'
-    _ = flow.get_root(document, comm=comm)
-    assert len(flow.nodes) == 1
-    assert flow.nodes[0]["id"] == "n1"
-
-
-def test_reactflow_add_node_with_arbitrary_object(document, comm) -> None:
-    """Test that arbitrary objects (e.g., HoloViews) work as node views via pn.panel().
-
-    This addresses issue #13 where objects without __panel__() method
-    (like HoloViews Curve objects) would raise AttributeError.
-    """
-
-    class MockPlot:
-        """Mock object simulating HoloViews/hvplot objects (no __panel__ method)."""
-
-        def __repr__(self):
-            return "MockPlot(data)"
-
-    flow = ReactFlow()
-    mock_plot = MockPlot()
-    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "label": "Plot Node", "data": {}, "view": mock_plot})
-
-    # This should not raise AttributeError about '_models'
-    # The object should be converted via pn.panel()
-    _ = flow.get_root(document, comm=comm)
-    assert len(flow.nodes) == 1
-    assert flow.nodes[0]["id"] == "n1"
-
-
 def test_reactflow_events_and_selection() -> None:
     flow = ReactFlow()
     events = []

tests/test_core.py

@@ -1,8 +1,81 @@
-"""Core tests module."""
+"""Tests for ReactFlow model creation."""
 
-import panel_reactflow  # noqa
+from panel.pane import Markdown
+from panel.viewable import Viewer
 
+from panel_reactflow import ReactFlow
 
-def test_example():
-    """Test example."""
-    assert panel_reactflow
+
+def test_reactflow_add_node_with_arbitrary_object(document, comm) -> None:
+    """Test that arbitrary objects (e.g., HoloViews) work as node views via pn.panel().
+
+    This addresses issue #13 where objects without __panel__() method
+    (like HoloViews Curve objects) would raise AttributeError.
+    """
+
+    class MockPlot:
+        """Mock object simulating HoloViews/hvplot objects (no __panel__ method)."""
+
+        def __repr__(self):
+            return "MockPlot(data)"
+
+    flow = ReactFlow()
+    mock_plot = MockPlot()
+    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "label": "Plot Node", "data": {}, "view": mock_plot})
+
+    # This should not raise AttributeError about '_models'
+    # The object should be converted via pn.panel()
+    _ = flow.get_root(document, comm=comm)
+    assert len(flow.nodes) == 1
+    assert flow.nodes[0]["id"] == "n1"
+
+
+def test_view_idx_updates_on_remove_node(document, comm) -> None:
+    flow = ReactFlow()
+    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "data": {}, "view": Markdown("A")})
+    flow.add_node({"id": "n2", "position": {"x": 1, "y": 1}, "data": {}, "view": Markdown("B")})
+    flow.add_node({"id": "n3", "position": {"x": 2, "y": 2}, "data": {}})
+
+    model = flow.get_root(document, comm=comm)
+
+    flow.remove_node("n1")
+
+    remaining = {node["id"]: node for node in model.data.nodes}
+    assert remaining["n2"]["data"]["view_idx"] == 0
+    assert remaining["n3"]["data"].get("view_idx") is None
+
+
+def test_reactflow_add_node_with_viewer(document, comm) -> None:
+    """Test that Viewer objects with __panel__() method work as node views."""
+
+    class MyViewer(Viewer):
+        def __panel__(self):
+            return Markdown("Hello from Viewer!")
+
+    flow = ReactFlow()
+    my_viewer = MyViewer()
+    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "label": "Viewer Node", "data": {}, "view": my_viewer})
+
+    # This should not raise AttributeError about '_models'
+    _ = flow.get_root(document, comm=comm)
+    assert len(flow.nodes) == 1
+    assert flow.nodes[0]["id"] == "n1"
+
+
+def test_reactflow_add_node_dynamically_creates_views(document, comm):
+    flow = ReactFlow()
+    model = flow.get_root(document, comm=comm)
+    assert model.children == [
+        "_views",
+        "_node_editor_views",
+        "_edge_editor_views",
+        "top_panel",
+        "bottom_panel",
+        "left_panel",
+        "right_panel",
+    ]
+
+    flow.add_node({"id": "n1", "position": {"x": 0, "y": 0}, "label": "Viewer Node", "data": {}, "view": Markdown("foo")})
+
+    assert len(model.data._views) == 1
+    assert len(model.data._node_editor_views) == 1