Don't pass label when creating color cycle scout (#3116)

* Don't pass label when creating color cycle scout

* Update release notes

Author: mwaskom

doc/whatsnew/v0.12.2.rst

@@ -2,4 +2,6 @@
 v0.12.2 (Unreleased)
 --------------------
 
-- Added the :class:`objects.KDE` stat (:pr:`3111`).
+- |Feature| Added the :class:`objects.KDE` stat (:pr:`3111`).
+
+- |Fix| Fixed a regression in v0.12.0 where manually-added labels could have duplicate legend entries (:pr:`3116`).

seaborn/utils.py

@@ -95,6 +95,9 @@ def _default_color(method, hue, color, kws):
         #      warnings.warn(msg)
         return None
 
+    kws = kws.copy()
+    kws.pop("label", None)
+
     if color is not None:
         return color
 

tests/test_distributions.py

@@ -1816,6 +1816,13 @@ def test_step_line_kwargs(self, flat_series):
         assert line.get_linewidth() == lw
         assert line.get_linestyle() == ls
 
+    def test_label(self, flat_series):
+
+        ax = histplot(flat_series, label="a label")
+        handles, labels = ax.get_legend_handles_labels()
+        assert len(handles) == 1
+        assert labels == ["a label"]
+
 
 class TestHistPlotBivariate: