From 39ea5a494c25486d031e1b5b1350aa8ac1b91946 Mon Sep 17 00:00:00 2001
From: David Stansby <dstansby@gmail.com>
Date: Fri, 26 Oct 2018 16:27:01 +0100
Subject: [PATCH] Allow unit input to FancyArrowPatch

---
 lib/matplotlib/patches.py            | 14 ++++++++++++--
 lib/matplotlib/tests/test_patches.py | 11 ++++++++++-
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/lib/matplotlib/patches.py b/lib/matplotlib/patches.py
index db15c1d1a148..fd45b44861a7 100644
--- a/lib/matplotlib/patches.py
+++ b/lib/matplotlib/patches.py
@@ -571,6 +571,14 @@ def get_path(self):
     def get_window_extent(self, renderer=None):
         return self.get_path().get_extents(self.get_transform())
 
+    def _convert_xy_units(self, xy):
+        """
+        Convert x and y units for a tuple (x, y)
+        """
+        x = self.convert_xunits(xy[0])
+        y = self.convert_yunits(xy[1])
+        return (x, y)
+
 
 patchdoc = artist.kwdoc(Patch)
 for k in ('Rectangle', 'Circle', 'RegularPolygon', 'Polygon', 'Wedge', 'Arrow',
@@ -4253,8 +4261,10 @@ def get_path_in_displaycoord(self):
         dpi_cor = self.get_dpi_cor()
 
         if self._posA_posB is not None:
-            posA = self.get_transform().transform_point(self._posA_posB[0])
-            posB = self.get_transform().transform_point(self._posA_posB[1])
+            posA = self._convert_xy_units(self._posA_posB[0])
+            posB = self._convert_xy_units(self._posA_posB[1])
+            posA = self.get_transform().transform_point(posA)
+            posB = self.get_transform().transform_point(posB)
             _path = self.get_connectionstyle()(posA, posB,
                                                patchA=self.patchA,
                                                patchB=self.patchB,
diff --git a/lib/matplotlib/tests/test_patches.py b/lib/matplotlib/tests/test_patches.py
index 7b029a0c74af..345ac0ec63f7 100644
--- a/lib/matplotlib/tests/test_patches.py
+++ b/lib/matplotlib/tests/test_patches.py
@@ -6,7 +6,7 @@
 import pytest
 
 from matplotlib.cbook import MatplotlibDeprecationWarning
-from matplotlib.patches import Polygon, Rectangle
+from matplotlib.patches import Polygon, Rectangle, FancyArrowPatch
 from matplotlib.testing.decorators import image_comparison, check_figures_equal
 import matplotlib.pyplot as plt
 from matplotlib import (
@@ -468,3 +468,12 @@ def test_shadow(fig_test, fig_ref):
         alpha=.5)
     a2.add_patch(shadow)
     a2.add_patch(rect)
+
+
+def test_fancyarrow_units():
+    from datetime import datetime
+    # Smoke test to check that FancyArrowPatch works with units
+    dtime = datetime(2000, 1, 1)
+    fig, ax = plt.subplots()
+    arrow = FancyArrowPatch((0, dtime), (0.01, dtime))
+    ax.add_patch(arrow)