Fix theta_label_pad being overwritten by facet margin padding

facet.set_limits_breaks_and_labels() called ax.tick_params(axis='x', pad=pad_x)
after coord.draw(), silently overwriting any custom theta_label_pad set by
coord_radial. Add a post_setup_ax() hook to the coord base class, called by
set_limits_breaks_and_labels after the margin pad, so coord_radial can apply
theta_label_pad at the correct point in the rendering pipeline.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: iangow

plotnine/coords/coord.py

@@ -112,6 +112,14 @@ def draw(self, axs: list) -> None:
         add elements such as polar grid lines.
         """
 
+    def post_setup_ax(self, ax: Any) -> None:
+        """
+        Hook called for each axes after set_limits_breaks_and_labels.
+
+        Override in subclasses to apply per-axes settings that must
+        run after the facet has set tick positions and label padding.
+        """
+
     def labels(self, cur_labels: labels_view) -> labels_view:
         """
         Modify labels

plotnine/coords/coord_radial.py

@@ -254,7 +254,7 @@ def draw(self, axs: list[Axes]) -> None:
                 else:
                     ax.set_rlabel_position(np.degrees(float(self.r_axis_inside)))
 
-            # Push theta tick labels away from the outer circle so they don't
-            # sit right on the spine.
-            if self.theta_labels or self.end is not None:
-                ax.tick_params(axis="x", pad=self.theta_label_pad)
+    def post_setup_ax(self, ax: Axes) -> None:
+        """Apply theta label pad after facet has set tick positions and padding."""
+        if self.theta_labels or self.end is not None:
+            ax.tick_params(axis="x", pad=self.theta_label_pad)

plotnine/facets/facet.py

@@ -355,6 +355,7 @@ def _inf_to_none(
 
         ax.tick_params(axis="x", which="major", pad=pad_x)
         ax.tick_params(axis="y", which="major", pad=pad_y)
+        self.coordinates.post_setup_ax(ax)
 
     def __deepcopy__(self, memo: dict[Any, Any]) -> facet:
         """