FIX/ENH: do more clean up when removing axes

This adds clean up of the shared axes `Grouper` objects as part of removing an axes. `_reset_loc_form` is required because the locator/formatters end up bound to the axis objects of the last axes object (all of the Axes in the group share the same formatter/locator objects but have different Axis objects so that all but one of the Axis objects can be made not visible to not over-draw). If these are not re-bound to a still visible axes then changing the limits will change the view limits, but not the tick locations. closes #5663
matplotlib · WeatherGod · Dec 15, 2015 · Dec 15, 2015 · Dec 15, 2015 · Dec 15, 2015
commit 0245db95ee5fb23271f1a68e979f7893070fd0ab
diff --git a/lib/matplotlib/figure.py b/lib/matplotlib/figure.py
@@ -916,7 +916,7 @@ def add_axes(self, *args, **kwargs):

        self._axstack.add(key, a)
        self.sca(a)
-        a._remove_method = lambda ax: self.delaxes(ax)
+        a._remove_method = self.__remove_ax
        self.stale = True
        a.stale_callback = _stale_figure_callback
        return a
@@ -1006,11 +1006,37 @@ def add_subplot(self, *args, **kwargs):

        self._axstack.add(key, a)
        self.sca(a)
-        a._remove_method = lambda ax: self.delaxes(ax)
+        a._remove_method = self.__remove_ax
        self.stale = True
        a.stale_callback = _stale_figure_callback
        return a

+    def __remove_ax(self, ax):
+        def _reset_loc_form(axis):
+            axis.set_major_formatter(axis.get_major_formatter())
+            axis.set_major_locator(axis.get_major_locator())
+            axis.set_minor_formatter(axis.get_minor_formatter())
+            axis.set_minor_locator(axis.get_minor_locator())
+
+        def _break_share_link(ax, grouper):
+            siblings = grouper.get_siblings(ax)
+            if len(siblings) > 1:
+                grouper.remove(ax)
+                for last_ax in siblings:
+                    if ax is last_ax:
+                        continue
+                    return last_ax
+            return None
+
+        self.delaxes(ax)
+        last_ax = _break_share_link(ax, ax._shared_y_axes)
+        if last_ax is not None:
+            _reset_loc_form(last_ax.yaxis)
+
+        last_ax = _break_share_link(ax, ax._shared_x_axes)
+        if last_ax is not None:
+            _reset_loc_form(last_ax.xaxis)
+
    def clf(self, keep_observers=False):
        """
        Clear the figure.