Adding debug info in the CI for failing test

Author: Marc Garcia

pandas/tests/plotting/test_misc.py

@@ -262,6 +262,13 @@ def test_parallel_coordinates_with_sorted_labels(self):
         prev_next_tupels = zip([i for i in ordered_color_label_tuples[0:-1]],
                                [i for i in ordered_color_label_tuples[1:]])
         for prev, nxt in prev_next_tupels:
+            # FIXME: Showing in the CI what's in ordered_color_label_tuples
+            if ((isinstance(prev[1], list) and isinstance(nxt[1], str))
+                    or (isinstance(prev[0], list)
+                        and isinstance(nxt[0], str))):
+                raise ValueError('ordered_color_label_tuples: {}'.format(
+                    ordered_color_label_tuples))
+
             # labels and colors are ordered strictly increasing
             assert prev[1] < nxt[1] and prev[0] < nxt[0]