Allow sharing Locators and Formatters across Axises.

anntzer · anntzer · commit f4e4f2691f62 · 2019-10-04T09:43:29.000+02:00
diff --git a/lib/matplotlib/axis.py b/lib/matplotlib/axis.py
@@ -643,12 +643,20 @@ class Ticker:
     """
 
     def __init__(self):
+        self._axis = None
         self._locator = None
         self._formatter = None
+        self._locator_is_default = True
+        self._formatter_is_default = True
+
+    # The machinery below allows TickHelpers to be shared over multiple Axis.
 
     @property
     def locator(self):
-        return self._locator
+        locator = self._locator
+        if locator is not None:
+            locator.set_axis(self._axis)
+        return locator
 
     @locator.setter
     def locator(self, locator):
@@ -661,7 +669,10 @@ def locator(self, locator):
 
     @property
     def formatter(self):
-        return self._formatter
+        formatter = self._formatter
+        if formatter is not None:
+            formatter.set_axis(self._axis)
+        return formatter
 
     @formatter.setter
     def formatter(self, formatter):
@@ -672,6 +683,10 @@ def formatter(self, formatter):
                 "and support for them will be removed %(removal)s.")
         self._formatter = formatter
 
+    @locator.setter
+    def locator(self, locator):
+        self._locator = locator
+
 
 class _LazyTickList:
     """
@@ -759,8 +774,8 @@ def __init__(self, axes, pickradius=15):
         self.isDefault_label = True
 
         self.axes = axes
-        self.major = Ticker()
-        self.minor = Ticker()
+        self._major = Ticker()
+        self._minor = Ticker()
         self.callbacks = cbook.CallbackRegistry()
 
         self._autolabelpos = True
@@ -779,6 +794,60 @@ def __init__(self, axes, pickradius=15):
         self.cla()
         self._set_scale('linear')
 
+    # The machinery below allows TickHelpers to be shared over multiple Axis.
+
+    @property
+    def major(self):
+        major = self._major
+        major._axis = self
+        return major
+
+    @major.setter
+    def major(self, major):
+        self._major = major
+
+    @property
+    def minor(self):
+        minor = self._minor
+        minor._axis = self
+        return minor
+
+    @minor.setter
+    def minor(self, minor):
+        self._minor = minor
+
+    @property
+    def isDefault_majloc(self):
+        return self.major._locator_is_default
+
+    @isDefault_majloc.setter
+    def isDefault_majloc(self, value):
+        self.major._locator_is_default = value
+
+    @property
+    def isDefault_majfmt(self):
+        return self.major._formatter_is_default
+
+    @isDefault_majfmt.setter
+    def isDefault_majfmt(self, value):
+        self.major._formatter_is_default = value
+
+    @property
+    def isDefault_minloc(self):
+        return self.minor._locator_is_default
+
+    @isDefault_minloc.setter
+    def isDefault_minloc(self, value):
+        self.minor._locator_is_default = value
+
+    @property
+    def isDefault_minfmt(self):
+        return self.minor._formatter_is_default
+
+    @isDefault_minfmt.setter
+    def isDefault_minfmt(self, value):
+        self.minor._formatter_is_default = value
+
     # During initialization, Axis objects often create ticks that are later
     # unused; this turns out to be a very slow step.  Instead, use a custom
     # descriptor to make the tick lists lazy and instantiate them as needed.
diff --git a/lib/matplotlib/figure.py b/lib/matplotlib/figure.py
@@ -1557,60 +1557,12 @@ def delaxes(self, ax):
         """
         Remove the `~.axes.Axes` *ax* from the figure; update the current axes.
         """
-
-        def _reset_locators_and_formatters(axis):
-            # Set the formatters and locators to be associated with axis
-            # (where previously they may have been associated with another
-            # Axis isntance)
-            #
-            # Because set_major_formatter() etc. force isDefault_* to be False,
-            # we have to manually check if the original formatter was a
-            # default and manually set isDefault_* if that was the case.
-            majfmt = axis.get_major_formatter()
-            isDefault = majfmt.axis.isDefault_majfmt
-            axis.set_major_formatter(majfmt)
-            if isDefault:
-                majfmt.axis.isDefault_majfmt = True
-
-            majloc = axis.get_major_locator()
-            isDefault = majloc.axis.isDefault_majloc
-            axis.set_major_locator(majloc)
-            if isDefault:
-                majloc.axis.isDefault_majloc = True
-
-            minfmt = axis.get_minor_formatter()
-            isDefault = majloc.axis.isDefault_minfmt
-            axis.set_minor_formatter(minfmt)
-            if isDefault:
-                minfmt.axis.isDefault_minfmt = True
-
-            minloc = axis.get_minor_locator()
-            isDefault = majloc.axis.isDefault_minloc
-            axis.set_minor_locator(minloc)
-            if isDefault:
-                minloc.axis.isDefault_minloc = True
-
-        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 not last_ax:
-                        return last_ax
-            return None
-
         self._axstack.remove(ax)
         for func in self._axobservers:
             func(self)
         self.stale = True
-
-        last_ax = _break_share_link(ax, ax._shared_y_axes)
-        if last_ax is not None:
-            _reset_locators_and_formatters(last_ax.yaxis)
-
-        last_ax = _break_share_link(ax, ax._shared_x_axes)
-        if last_ax is not None:
-            _reset_locators_and_formatters(last_ax.xaxis)
+        ax._shared_x_axes.remove(ax)
+        ax._shared_y_axes.remove(ax)
 
     def clf(self, keep_observers=False):
         """
