Allow polygon to take a list or tuple and add a test

skimage/draw/_draw.pyx

@@ -268,6 +268,8 @@ def polygon(y, x, shape=None):
            [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]], dtype=uint8)
 
     """
+    x = np.asanyarray(x)
+    y = np.asanyarray(y)
 
     cdef Py_ssize_t nr_verts = x.shape[0]
     cdef Py_ssize_t minr = int(max(0, y.min()))

skimage/draw/tests/test_draw.py

@@ -122,9 +122,8 @@ def test_line_equal_aliasing_horizontally_vertically():
 
 def test_polygon_rectangle():
     img = np.zeros((10, 10), 'uint8')
-    poly = np.array(((1, 1), (4, 1), (4, 4), (1, 4), (1, 1)))
 
-    rr, cc = polygon(poly[:, 0], poly[:, 1])
+    rr, cc = polygon((1, 4, 4, 1, 1), (1, 1, 4, 4, 1))
     img[rr, cc] = 1
 
     img_ = np.zeros((10, 10))