matplotlib
diff --git a/‎lib/mpl_toolkits/mplot3d/art3d.py
Copy file name to clipboardExpand all lines: lib/mpl_toolkits/mplot3d/art3d.py
+1-1Lines changed: 1 addition & 1 deletion b/‎lib/mpl_toolkits/mplot3d/art3d.py
Copy file name to clipboardExpand all lines: lib/mpl_toolkits/mplot3d/art3d.py
+1-1Lines changed: 1 addition & 1 deletion
diff --git a/‎lib/mpl_toolkits/mplot3d/tests/test_axes3d.py
Copy file name to clipboardExpand all lines: lib/mpl_toolkits/mplot3d/tests/test_axes3d.py
+10Lines changed: 10 additions & 0 deletions b/‎lib/mpl_toolkits/mplot3d/tests/test_axes3d.py
Copy file name to clipboardExpand all lines: lib/mpl_toolkits/mplot3d/tests/test_axes3d.py
+10Lines changed: 10 additions & 0 deletions
@@ -880,7 +880,7 @@ def __init__(self, verts, *args, zsort='average', shade=False,
                 kwargs['edgecolors'] = _shade_colors(
                     edgecolors, normals, lightsource
                 )
-            if facecolors is None and edgecolors in None:
+            if facecolors is None and edgecolors is None:
                 raise ValueError(
                     "You must provide facecolors, edgecolors, or both for "
                     "shade to work.")
 
@@ -2176,3 +2176,13 @@ def test_mutating_input_arrays_y_and_z(fig_test, fig_ref):
     y = [0.0, 0.0, 0.0]
     z = [0.0, 0.0, 0.0]
     ax2.plot(x, y, z, 'o-')
+
+
+def test_Poly3DCollection_init_value_error():
+    # smoke test to ensure the input check works
+    # GH#26420
+    with pytest.raises(ValueError,
+                       match='You must provide facecolors, edgecolors, '
+                        'or both for shade to work.'):
+        poly = np.array([[0, 0, 1], [0, 1, 1], [0, 0, 0]], float)
+        c = art3d.Poly3DCollection([poly], shade=True)