ListedColormap: don't pass n colors (#145)

Author: mathause

mplotutils/_colormaps.py

@@ -55,7 +55,7 @@ def _color_palette(cmap, n_colors):
     colors_i = np.linspace(0, 1.0, n_colors)
     if isinstance(cmap, (list, tuple)):
         # we have a list of colors
-        cmap = ListedColormap(cmap, N=n_colors)
+        cmap = ListedColormap(cmap)
         pal = cmap(colors_i)
     elif isinstance(cmap, str):
         # we have some sort of named palette
@@ -71,7 +71,7 @@ def _color_palette(cmap, n_colors):
                 pal = color_palette(cmap, n_colors=n_colors)
             except (ValueError, ImportError):
                 # or maybe we just got a single color as a string
-                cmap = ListedColormap([cmap], N=n_colors)
+                cmap = ListedColormap([cmap] * n_colors)
                 pal = cmap(colors_i)
     else:
         # cmap better be a LinearSegmentedColormap (e.g. viridis)

mplotutils/tests/test_hatch.py

@@ -151,6 +151,7 @@ def test_hatch_linewidth_mpl_lt_310(function):
 
 
 @requires_mpl_ge_310
+@pytest.mark.filterwarnings("ignore:Passing 'N' to ListedColormap is deprecated")
 @pytest.mark.parametrize("function", HATCH_FUNCTIONS)
 def test_hatch_linewidth_mpl_ge_310(function):