Lazily construct sticky edges

scottshambaugh · scottshambaugh · commit 546266911976 · 2026-03-05T22:17:31.000-07:00
diff --git a/lib/matplotlib/artist.py b/lib/matplotlib/artist.py
@@ -223,7 +223,7 @@ def __init__(self):
         self._snap = None
         self._sketch = mpl.rcParams['path.sketch']
         self._path_effects = mpl.rcParams['path.effects']
-        self._sticky_edges = _XYPair([], [])
+        self._sticky_edges = None
         self._in_layout = True
 
     def __getstate__(self):
@@ -1209,6 +1209,8 @@ def sticky_edges(self):
         >>> artist.sticky_edges.y[:] = (ymin, ymax)
 
         """
+        if self._sticky_edges is None:
+            self._sticky_edges = _XYPair([], [])
         return self._sticky_edges
 
     def update_from(self, other):
@@ -1223,8 +1225,11 @@ def update_from(self, other):
         self._label = other._label
         self._sketch = other._sketch
         self._path_effects = other._path_effects
-        self.sticky_edges.x[:] = other.sticky_edges.x.copy()
-        self.sticky_edges.y[:] = other.sticky_edges.y.copy()
+        if other._sticky_edges is not None:
+            self.sticky_edges.x[:] = other._sticky_edges.x.copy()
+            self.sticky_edges.y[:] = other._sticky_edges.y.copy()
+        else:
+            self._sticky_edges = None
         self.pchanged()
         self.stale = True
 
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -3016,23 +3016,25 @@ def autoscale_view(self, tight=None, scalex=True, scaley=True):
 
         x_stickies = y_stickies = np.array([])
         if self.use_sticky_edges:
+            # Use ._children and ._sticky_edges directly, because the extra
+            # artists in .get_children() (spines, axes, titles, etc.) never
+            # have sticky edges, so we can skip them for performance.
             if self._xmargin and scalex and self.get_autoscalex_on():
-                # Use ._children and ._sticky_edges directly, because the extra
-                # artists in .get_children() (spines, axes, titles, etc.) never
-                # have sticky edges, so we can skip them for performance.
                 x_sticky_lists = []
                 for ax in x_shared:
                     for artist in ax._children:
-                        if artist._sticky_edges.x:
-                            x_sticky_lists.append(artist._sticky_edges.x)
+                        sticky_edges = artist._sticky_edges
+                        if sticky_edges is not None and sticky_edges.x:
+                            x_sticky_lists.append(sticky_edges.x)
                 if x_sticky_lists:
                     x_stickies = np.sort(np.concatenate(x_sticky_lists))
             if self._ymargin and scaley and self.get_autoscaley_on():
                 y_sticky_lists = []
                 for ax in y_shared:
                     for artist in ax._children:
-                        if artist._sticky_edges.y:
-                            y_sticky_lists.append(artist._sticky_edges.y)
+                        sticky_edges = artist._sticky_edges
+                        if sticky_edges is not None and sticky_edges.y:
+                            y_sticky_lists.append(sticky_edges.y)
                 if y_sticky_lists:
                     y_stickies = np.sort(np.concatenate(y_sticky_lists))
         if self.get_xscale() == 'log':
