smoke test for hatchcolors coercion

Author: r3kste

lib/matplotlib/tests/test_collections.py

@@ -1453,3 +1453,36 @@ def test_collection_hatchcolor_fallback_logic():
     col = PathCollection([path], hatch='//')
     assert_array_equal(col.get_hatchcolor(),
                        mpl.colors.to_rgba_array(mpl.rcParams['patch.edgecolor']))
+
+
+@pytest.mark.parametrize('backend', ['agg', 'pdf', 'svg', 'ps'])
+def test_draw_path_collection_no_hatchcolor(backend):
+    from matplotlib.collections import PathCollection
+    path = mpath.Path.unit_rectangle()
+
+    plt.switch_backend(backend)
+    fig, ax = plt.subplots()
+    renderer = fig._get_renderer()
+
+    col = PathCollection([path], hatch='//')
+    ax.add_collection(col)
+
+    gc = renderer.new_gc()
+    transform = mtransforms.IdentityTransform()
+    paths = col.get_paths()
+    transforms = col.get_transforms()
+    offsets = col.get_offsets()
+    offset_trf = col.get_offset_transform()
+    facecolors = col.get_facecolor()
+    edgecolors = col.get_edgecolor()
+    linewidths = col.get_linewidth()
+    linestyles = col.get_linestyle()
+    antialiaseds = col.get_antialiased()
+    urls = col.get_urls()
+    offset_position = "screen"
+
+    renderer.draw_path_collection(
+        gc, transform, paths, transforms, offsets, offset_trf,
+        facecolors, edgecolors, linewidths, linestyles,
+        antialiaseds, urls, offset_position
+    )

src/_backend_agg_wrapper.cpp

@@ -236,11 +236,11 @@ PYBIND11_MODULE(_backend_agg, m, py::mod_gil_not_used())
              "gc"_a, "master_transform"_a, "paths"_a, "transforms"_a, "offsets"_a,
              "offset_trans"_a, "facecolors"_a, "edgecolors"_a, "linewidths"_a,
              "dashes"_a, "antialiaseds"_a, "ignored"_a, "offset_position"_a,
-             "hatchcolors"_a = nullptr)
+             "hatchcolors"_a = py::array_t<double>().reshape({0, 4}))
         .def("draw_quad_mesh", &PyRendererAgg_draw_quad_mesh,
              "gc"_a, "master_transform"_a, "mesh_width"_a, "mesh_height"_a,
              "coordinates"_a, "offsets"_a, "offset_trans"_a, "facecolors"_a,
-             "antialiased"_a, "edgecolors"_a, "hatchcolors"_a = nullptr)
+             "antialiased"_a, "edgecolors"_a, "hatchcolors"_a = py::array_t<double>().reshape({0, 4}))
         .def("draw_gouraud_triangles", &PyRendererAgg_draw_gouraud_triangles,
              "gc"_a, "points"_a, "colors"_a, "trans"_a = nullptr)