BUG: Fix box_handle_props initialization

lucaznch · lucaznch · commit 45071c9ba003 · 2026-05-20T19:49:36.000+01:00
diff --git a/lib/matplotlib/tests/test_widgets.py b/lib/matplotlib/tests/test_widgets.py
@@ -1717,6 +1717,44 @@ def test_polygon_selector_box(ax):
         tool._box.extents, (20.0, 40.0, 30.0, 40.0))
 
 
+def test_polygon_selector_box_props_handle_props(ax):
+    props = dict(color='r')
+    handle_props = dict(marker='o', markerfacecolor='w', markeredgecolor='r')
+    box_props = dict(linestyle=':', facecolor='c', edgecolor='b')
+    box_handle_props = dict(markeredgecolor='y')
+
+    tool = widgets.PolygonSelector(
+        ax, draw_bounding_box=True,
+        props=props, handle_props=handle_props,
+        box_props=box_props, box_handle_props=box_handle_props)
+
+    for event in [
+        *polygon_place_vertex(ax, (50, 50)),
+        *polygon_place_vertex(ax, (150, 50)),
+        *polygon_place_vertex(ax, (50, 150)),
+        *polygon_place_vertex(ax, (50, 50)),
+    ]:
+        event._process()
+
+    artist = tool._selection_artist
+    assert artist.get_color() == 'r'
+    for artist in tool._handles_artists:
+        assert artist.get_marker() == 'o'
+        assert artist.get_markerfacecolor() == 'w'
+        assert artist.get_markeredgecolor() == 'r'
+
+    box_artist = tool._box._selection_artist
+    assert box_artist.get_linestyle() == ':'
+    assert box_artist.get_facecolor() == mcolors.to_rgba('c')
+    assert box_artist.get_edgecolor() == mcolors.to_rgba('b')
+    for artist in tool._box._handles_artists:
+        # marker and markerfacecolor are inherited from handle_props
+        # markeredgecolor is overridden by box_handle_props.
+        assert artist.get_marker() == 'o'
+        assert artist.get_markerfacecolor() == 'w'
+        assert artist.get_markeredgecolor() == 'y'
+
+
 def test_polygon_selector_clear_method(ax):
     onselect = mock.Mock(spec=noop, return_value=None)
     tool = widgets.PolygonSelector(ax, onselect)
diff --git a/lib/matplotlib/widgets.py b/lib/matplotlib/widgets.py
@@ -4118,7 +4118,7 @@ def __init__(self, ax, onselect=None, *, useblit=False,
 
         if box_handle_props is None:
             box_handle_props = {}
-        self._box_handle_props = self._handle_props.update(box_handle_props)
+        self._box_handle_props = {**self._handle_props, **box_handle_props}
         self._box_props = box_props
 
     def _get_bbox(self):
