fix(curve_settings): edit curve copies and drop removed curves

bec_widgets/widgets/plots/waveform/settings/curve_settings/curve_tree.py

@@ -737,7 +737,11 @@ class CurveTree(BECWidget, QWidget):
             self.tree.collapseItem(item)
 
     def refresh_from_waveform(self):
-        """Clear the tree and rebuild from the waveform's existing curves if any, else add sample rows."""
+        """Clear the tree and rebuild from the waveform's existing curves if any, else add sample rows.
+
+        Each row works on a deep copy of its curve's config, so edits stay staged in the tree
+        and only reach the waveform through :meth:`send_curve_json`.
+        """
         if self.waveform is None:
             return
         self.tree.clear()
@@ -746,10 +750,20 @@ class CurveTree(BECWidget, QWidget):
         top_curves = [c for c in self.waveform.curves if c.config.source in ("device", "history")]
         dap_curves = [c for c in self.waveform.curves if c.config.source == "dap"]
         for dev in top_curves:
-            dr = CurveRow(self.tree, parent_item=None, config=dev.config, device_manager=self.dev)
+            dr = CurveRow(
+                self.tree,
+                parent_item=None,
+                config=dev.config.model_copy(deep=True),
+                device_manager=self.dev,
+            )
             for dap in dap_curves:
                 if dap.config.parent_label == dev.config.label:
-                    CurveRow(self.tree, parent_item=dr, config=dap.config, device_manager=self.dev)
+                    CurveRow(
+                        self.tree,
+                        parent_item=dr,
+                        config=dap.config.model_copy(deep=True),
+                        device_manager=self.dev,
+                    )
 
     def cleanup(self):
         """Cleanup the widget."""

bec_widgets/widgets/plots/waveform/waveform.py

@@ -1346,7 +1346,14 @@ class Waveform(PlotBase):
         return curve
 
     def _refresh_history_curves(self):
-        for curve in self._history_curves:
+        """
+        Reload the data of all history curves from their scans, e.g. after an x-axis change.
+
+        Curves whose source is no longer 'history' are dropped from the history tracking
+        instead of being filled with scan data they do not accept.
+        """
+        self._history_curves = [c for c in self._history_curves if c.config.source == "history"]
+        for curve in list(self._history_curves):
             scan_item = self.get_history_scan_item(
                 scan_id=curve.config.scan_id, scan_index=curve.config.scan_number
             )
@@ -1432,6 +1439,7 @@ class Waveform(PlotBase):
         """
         curve_list = self.curves
         self._dap_curves = []
+        self._history_curves = []
         self._sync_curves = []
         self._async_curves = []
         for curve in curve_list:
@@ -1518,6 +1526,12 @@ class Waveform(PlotBase):
         )
         curve.rpc_register.remove_rpc(curve)
 
+        # Stop tracking the removed curve, so history refreshes and DAP requests skip it
+        if curve in self._history_curves:
+            self._history_curves.remove(curve)
+        if curve in self._dap_curves:
+            self._dap_curves.remove(curve)
+
         # Remove itself from the DAP summary only for side panels
         if (
             curve.config.source == "dap"

tests/unit_tests/test_curve_settings.py

@@ -5,7 +5,12 @@ import pytest
 from bec_lib.scan_history import ScanHistory
 from qtpy.QtWidgets import QComboBox, QVBoxLayout
 
-from bec_widgets.tests.client_mocks import dap_plugin_message, mocked_client, mocked_client_with_dap
+from bec_widgets.tests.client_mocks import (
+    dap_plugin_message,
+    inject_scan_history,
+    mocked_client,
+    mocked_client_with_dap,
+)
 from bec_widgets.widgets.plots.waveform.settings.curve_settings.curve_setting import CurveSetting
 from bec_widgets.widgets.plots.waveform.settings.curve_settings.curve_tree import CurveTree
 from bec_widgets.widgets.plots.waveform.waveform import Waveform
@@ -470,3 +475,70 @@ def test_export_data_history_curve(curve_tree_fixture, scan_history_factory):
     assert exported["scan_number"] == 2
     assert exported["scan_id"] == "hid2"
     assert exported["label"] == "bpm4i-bpm4i-scan-2"
+
+
+##################################################
+# Staging of edits (issue #1314)
+##################################################
+
+
+@pytest.fixture
+def history_curve_setting(qtbot, mocked_client, scan_history_factory):
+    """
+    A Waveform showing one history curve of scan 1 (two scans in history) and a CurveSetting
+    targeting it.
+    """
+    wf = create_widget(qtbot, Waveform, client=mocked_client)
+    history_msgs = inject_scan_history(wf, scan_history_factory, ("hist1", 1), ("hist2", 2))
+    # The scan index combobox lists scans by number, so register those as well.
+    for msg in history_msgs:
+        wf.client.history._scan_numbers.append(msg.scan_number)
+    wf.x_mode = "index"
+    history_curve = wf.plot(device_y="bpm4i", signal_y="bpm4i", scan_id="hist1")
+    curve_setting = create_widget(qtbot, CurveSetting, parent=None, target_widget=wf)
+    curve_setting.mode_combo.setCurrentText("index")
+    return curve_setting, wf, history_curve
+
+
+def test_switch_history_curve_to_live_keeps_history_refresh_working(history_curve_setting):
+    """
+    Regression for #1314: switching a history curve to 'live' and applying must not leave a
+    device-source curve behind in the Waveform's history tracking. Previously the settings row
+    edited the live curve's config in place, so the removed history curve turned into a
+    device curve that the next history refresh tried to fill, raising
+    "Source device do not allow custom data setting."
+    """
+    curve_setting, wf, history_curve = history_curve_setting
+    row = curve_setting.curve_manager.tree.topLevelItem(0)
+    assert row.scan_index_combo.scan_id == "hist1"
+
+    row.scan_index_combo.set_scan_id(None)  # select 'live'
+    curve_setting.accept_changes()
+
+    # The next history refresh (x-axis change, Apply again, ...) must not raise.
+    wf._refresh_history_curves()
+
+    assert [curve.config.source for curve in wf.curves] == ["device"]
+    assert wf._history_curves == []
+    # The removed history curve kept its own configuration.
+    assert history_curve.config.source == "history"
+    assert history_curve.config.scan_id == "hist1"
+
+
+def test_curve_settings_edits_do_not_touch_live_curve_config(history_curve_setting):
+    """
+    Edits in the curve tree are staged on a copy of each curve's config: changing the color,
+    renormalizing colors or exporting the rows must leave the plotted curve untouched until
+    the Waveform applies the exported configuration (also #1304, Cancel keeps color edits).
+    """
+    curve_setting, wf, history_curve = history_curve_setting
+    curve_manager = curve_setting.curve_manager
+    original_config = history_curve.config.model_dump()
+
+    row = curve_manager.tree.topLevelItem(0)
+    curve_manager.renormalize_colors()
+    row.color_button.set_color("#123456")
+    row.scan_index_combo.set_scan_id(None)  # select 'live'
+    curve_manager.export_all_curves()
+
+    assert history_curve.config.model_dump() == original_config

tests/unit_tests/test_waveform.py

@@ -1892,6 +1892,63 @@ def test_history_curve_x_modes_post_plot(qtbot, mocked_client, scan_history_fact
     assert c.config.current_x_mode == mode
 
 
+@pytest.mark.parametrize("removal", ["remove_curve", "clear_all"])
+def test_removed_history_curve_leaves_history_tracking(
+    qtbot, mocked_client, scan_history_factory, removal
+):
+    """
+    Regression for #1314: a removed history curve must not stay in the list of curves
+    refreshed from the scan history.
+    """
+    wf = create_widget(qtbot, Waveform, client=mocked_client)
+    inject_scan_history(wf, scan_history_factory, ("hist1", 1))
+    wf.x_mode = "index"
+    c = wf.plot(device_y="bpm4i", signal_y="bpm4i", scan_id="hist1")
+    assert wf._history_curves == [c]
+
+    if removal == "remove_curve":
+        wf.remove_curve(c.name())
+    else:
+        wf.clear_all()
+
+    assert wf._history_curves == []
+
+
+def test_history_refresh_skips_curve_that_is_no_longer_history(
+    qtbot, mocked_client, scan_history_factory
+):
+    """
+    Regression for #1314: a curve whose source is no longer 'history' is dropped from the
+    history refresh instead of raising "Source device do not allow custom data setting."
+    """
+    wf = create_widget(qtbot, Waveform, client=mocked_client)
+    inject_scan_history(wf, scan_history_factory, ("hist1", 1))
+    wf.x_mode = "index"
+    c = wf.plot(device_y="bpm4i", signal_y="bpm4i", scan_id="hist1")
+    c.config.source = "device"
+    c.config.scan_id = None
+    c.config.scan_number = None
+
+    wf._refresh_history_curves()
+
+    assert wf._history_curves == []
+
+
+def test_removed_dap_curve_leaves_dap_tracking(qtbot, mocked_client_with_dap):
+    """
+    Removing a device curve also removes its DAP child; neither may stay tracked as a DAP curve.
+    """
+    wf = create_widget(qtbot, Waveform, client=mocked_client_with_dap)
+    wf.plot(arg1="bpm4i", label="bpm4i-bpm4i")
+    dap_curve = wf.add_dap_curve(device_label="bpm4i-bpm4i", dap_name="GaussianModel")
+    assert wf._dap_curves == [dap_curve]
+
+    wf.remove_curve("bpm4i-bpm4i")
+
+    assert wf.curves == []
+    assert wf._dap_curves == []
+
+
 def test_history_curve_incompatible_x_mode_hides_curve(qtbot, mocked_client, scan_history_factory):
     """
     Test that setting an x_mode not present in stored data hides the history curve.