Test invalid input for selem

skimage/morphology/tests/test_reconstruction.py

@@ -87,6 +87,14 @@ def test_invalid_seed():
                   method='erosion')
 
 
+def test_invalid_selem():
+    seed = np.ones((5, 5))
+    mask = np.ones((5, 5))
+    selem =
+    assert_raises(ValueError, reconstruction, seed, mask, np.ones((2, 2)))
+    reconstruction(seed, mask, np.ones((3, 3)))
+
+
 if __name__ == '__main__':
     from numpy import testing
     testing.run_module_suite()