Backport PR #21559: Fix eventplot units

story645 · meeseeksmachine · commit c4145c542d21 · 2021-11-08T07:40:00.000Z
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -1253,10 +1253,11 @@ def eventplot(self, positions, orientation='horizontal', lineoffsets=1,
         --------
         .. plot:: gallery/lines_bars_and_markers/eventplot_demo.py
         """
-        # We do the conversion first since not all unitized data is uniform
-        positions, lineoffsets, linelengths = self._process_unit_info(
-            [("x", positions), ("y", lineoffsets), ("y", linelengths)], kwargs)
 
+        lineoffsets, linelengths = self._process_unit_info(
+                [("y", lineoffsets), ("y", linelengths)], kwargs)
+
+        # fix positions, noting that it can be a list of lists:
         if not np.iterable(positions):
             positions = [positions]
         elif any(np.iterable(position) for position in positions):
@@ -1267,6 +1268,11 @@ def eventplot(self, positions, orientation='horizontal', lineoffsets=1,
         if len(positions) == 0:
             return []
 
+        poss = []
+        for position in positions:
+            poss += self._process_unit_info([("x", position)], kwargs)
+        positions = poss
+
         # prevent 'singular' keys from **kwargs dict from overriding the effect
         # of 'plural' keyword arguments (e.g. 'color' overriding 'colors')
         colors = cbook._local_over_kwdict(colors, kwargs, 'color')
@@ -4308,9 +4314,7 @@ def scatter(self, x, y, s=None, c=None, marker=None, cmap=None, norm=None,
 
         """
         # Process **kwargs to handle aliases, conflicts with explicit kwargs:
-
         x, y = self._process_unit_info([("x", x), ("y", y)], kwargs)
-
         # np.ma.ravel yields an ndarray, not a masked array,
         # unless its argument is a masked array.
         x = np.ma.ravel(x)
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -4116,6 +4116,21 @@ def test_eventplot_orientation(data, orientation):
     plt.draw()
 
 
+@check_figures_equal(extensions=['png'])
+def test_eventplot_units_list(fig_test, fig_ref):
+    # test that list of lists converted properly:
+    ts_1 = [datetime.datetime(2021, 1, 1), datetime.datetime(2021, 1, 2),
+            datetime.datetime(2021, 1, 3)]
+    ts_2 = [datetime.datetime(2021, 1, 15), datetime.datetime(2021, 1, 16)]
+
+    ax = fig_ref.subplots()
+    ax.eventplot(ts_1, lineoffsets=0)
+    ax.eventplot(ts_2, lineoffsets=1)
+
+    ax = fig_test.subplots()
+    ax.eventplot([ts_1, ts_2])
+
+
 @image_comparison(['marker_styles.png'], remove_text=True)
 def test_marker_styles():
     fig, ax = plt.subplots()
