BUG: Allow test suite to pass with scipy < 0.9.

skimage/morphology/convex_hull.py

@@ -1,7 +1,6 @@
 __all__ = ['convex_hull']
 
 import numpy as np
-from scipy.spatial import Delaunay
 from ._pnpoly import points_inside_poly, grid_points_inside_poly
 from ._convex_hull import possible_hull
 
@@ -44,6 +43,12 @@ def convex_hull(image):
 
     coords = coords_corners
 
+    try:
+        from scipy.spatial import Delaunay
+    except ImportError:
+        raise ImportError('Could not import scipy.spatial, only available in '
+                          'scipy >= 0.9.')
+
     # Find the convex hull
     chull = Delaunay(coords).convex_hull
     v = coords[np.unique(chull)]

skimage/morphology/tests/test_convex_hull.py

@@ -1,8 +1,16 @@
 import numpy as np
 from numpy.testing import assert_array_equal
+from numpy.testing.decorators import skipif
 from skimage.morphology import convex_hull
 from skimage.morphology._convex_hull import possible_hull
 
+try:
+    import scipy.spatial
+    scipy_spatial = True
+except ImportError:
+    scipy_spatial = False
+
+@skipif(not scipy_spatial)
 def test_basic():
     image = np.array(
         [[0, 0, 0, 0, 0, 0, 0, 0, 0],
@@ -22,7 +30,7 @@ def test_basic():
 
     assert_array_equal(convex_hull(image), expected)
 
-
+@skipif(not scipy_spatial)
 def test_possible_hull():
     image = np.array(
         [[0, 0, 0, 0, 0, 0, 0, 0, 0],