Use the property setter of direction when initialising a SpanSelector and add test.

ericpre · ericpre · commit 92d1705e0763 · 2021-06-30T09:37:25.000+01:00
diff --git a/lib/matplotlib/tests/test_widgets.py b/lib/matplotlib/tests/test_widgets.py
@@ -259,6 +259,27 @@ def onselect(epress, erelease):
     assert tool.extents == (175, 185)
 
 
+def test_span_selector_direction():
+    ax = get_ax()
+
+    def onselect(epress, erelease):
+        pass
+
+    tool = widgets.SpanSelector(ax, onselect, 'horizontal', interactive=True)
+    assert tool.direction == 'horizontal'
+    assert tool._edge_handles.direction == 'horizontal'
+
+    with pytest.raises(ValueError):
+        tool = widgets.SpanSelector(ax, onselect, 'invalid_direction')
+
+    tool.direction = 'vertical'
+    assert tool.direction == 'vertical'
+    assert tool._edge_handles.direction == 'vertical'
+
+    with pytest.raises(ValueError):
+        tool.direction = 'invalid_string'
+
+
 def test_tool_line_handle():
     ax = get_ax()
 
diff --git a/lib/matplotlib/widgets.py b/lib/matplotlib/widgets.py
@@ -1990,7 +1990,7 @@ def __init__(self, ax, onselect, direction, minspan=0, useblit=False,
 
         rectprops['animated'] = self.useblit
 
-        self._direction = direction
+        self.direction = direction
 
         self._rect = None
         self.visible = True
@@ -2114,7 +2114,7 @@ def direction(self):
     def direction(self, direction):
         """Set the direction of the span selector."""
         _api.check_in_list(['horizontal', 'vertical'], direction=direction)
-        if direction != self._direction:
+        if hasattr(self, '_direction') and direction != self._direction:
             # remove previous artists
             self._rect.remove()
             if self._interactive:
@@ -2125,6 +2125,8 @@ def direction(self, direction):
             self.new_axes(self.ax)
             if self._interactive:
                 self._setup_edge_handle(self._edge_handles._line_props)
+        else:
+            self._direction = direction
 
     def _release(self, event):
         """Button release event handler."""
