feat: add option to force sticky_edges

andrzejnovak · andrzejnovak · commit 10ea1ebfd3c7 · 2020-10-05T19:01:18.000+02:00
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -6788,13 +6788,15 @@ def stairs(self, values, edges=None, *,
                                    orientation=orientation,
                                    fill=fill,
                                    **kwargs)
-        self.add_patch(patch)
+
         if baseline is None:
             baseline = 0
         if orientation == 'vertical':
             patch.sticky_edges.y.append(np.min(baseline))
         else:
             patch.sticky_edges.x.append(np.min(baseline))
+        self.force_sticky_edges = True
+        self.add_patch(patch)
         self._request_autoscale_view()
         return patch
 
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -1141,6 +1141,7 @@ def cla(self):
         self._ymargin = mpl.rcParams['axes.ymargin']
         self._tight = None
         self._use_sticky_edges = True
+        self._force_sticky_edges = False
         self._update_transScale()  # needed?
 
         self._get_lines = _process_plot_var_args(self)
@@ -2352,6 +2353,29 @@ def use_sticky_edges(self, b):
         self._use_sticky_edges = bool(b)
         # No effect until next autoscaling, which will mark the axes as stale.
 
+    @property
+    def force_sticky_edges(self):
+        """
+        When autoscaling, whether to enforce `Artist.sticky_edges`
+        values.
+
+        Default is ``False``.
+
+        By default, when ``sticky_edges`` are present the tighter
+        marging is used between the "automatic" and the "sticky".
+        Setting this to ``True`` forces the use of the specified margins,
+        even if sticky_edge value is far away from datalim.
+
+        The changing this property does not change the plot until
+        `autoscale` or `autoscale_view` is called.
+        """
+        return self._force_sticky_edges
+
+    @force_sticky_edges.setter
+    def force_sticky_edges(self, b):
+        self._force_sticky_edges = bool(b)
+        # No effect until next autoscaling, which will mark the axes as stale.
+
     def set_xmargin(self, m):
         """
         Set padding of X data limits prior to autoscaling.
@@ -2644,10 +2668,11 @@ def handle_single_axis(scale, autoscaleon, shared_axes, interval,
             x0, x1 = inverse_trans.transform([x0t - delta, x1t + delta])
 
             # Apply sticky bounds.
+            _f = self._force_sticky_edges
             if x0bound is not None:
-                x0 = max(x0, x0bound)
+                x0 = max(x0, x0bound) if not _f else x0bound
             if x1bound is not None:
-                x1 = min(x1, x1bound)
+                x1 = min(x1, x1bound) if not _f else x1bound
 
             if not self._tight:
                 x0, x1 = locator.view_limits(x0, x1)
