added some tests for the VirtualSource class and made the code a bit …

…more robust.

h5py/_hl/group.py

@@ -638,17 +638,33 @@ def __getitem__(self, *key):
             raise IndexError('Index rank is greater than dataset rank')
         # need to deal with integer inputs
         tmp = copy(self)
-        tmp.slice_list = list(key[0] + (slice(None, None, None),)*(len(self.shape)-len(key[0]))) # generate the right slice
+
+        if not isinstance(key, tuple):
+            key = tuple(key)
+        elif not isinstance(key[0],slice):
+            key  = key[0]
+        tmp.slice_list = list(key + (slice(None, None, None),)*(len(self.shape)-len(key))) # generate the right slice
+
         # sanitize this slice list to get rid of the nones and integers/floats(?)
-        tmp.slice_list = [slice(ix) if isinstance(ix, (int,float)) else ix for ix in tmp.slice_list]
-        new_shape = ()
+        tmp.slice_list = [slice(ix,ix+1,1) if isinstance(ix, (int,float)) else ix for ix in tmp.slice_list]
+        new_shape = []
         for ix,sl in enumerate(tmp.slice_list):
-            start = 0 if sl.start is None else sl.start
             step = 1 if sl.step is None else sl.step
-            stop = self.shape[ix]
-            new_shape+=((stop-start)/abs(step),)
+            if step>0:
+                start = 0 if sl.start is None else sl.start
+                stop = self.shape[ix] if sl.stop is None else sl.stop
+                new_shape.append((stop-start)/step)
+            elif step<0:
+                stop = 0 if sl.stop is None else sl.stop
+                start = self.shape[ix] if sl.start is None else sl.start
+                if start>stop: # this gets the same behaviour as numpy array
+                    new_shape.append((start-stop)/abs(step))
+                else:
+                    new_shape.append(0)
+            elif step==0:
+                raise IndexError("A step of 0 is not valid")
             tmp.slice_list[ix] = slice(start,stop,step)
-        tmp.shape = new_shape
+        tmp.shape = tuple(new_shape)
         return tmp
 
 class VirtualTarget(DatasetContainer):

h5py/tests/hl/test_vds/__init__.py

@@ -1,3 +1,5 @@
+from __future__ import absolute_import
+
 from .test_eiger_high_level import *
 from .test_eiger_low_level import *
 from .test_excalibur_high_level import *

h5py/tests/hl/test_vds/test_eiger_low_level.py

@@ -10,7 +10,7 @@
 import tempfile
 
 
-class EigerLowLevelTest(unittest.TestCase):
+class TestEigerLowLevel(unittest.TestCase):
     def setUp(self):
         self.working_dir = tempfile.mkdtemp()
         self.fname = ['raw_file_1.h5', 'raw_file_2.h5', 'raw_file_3.h5']

h5py/tests/hl/test_vds/test_excalibur_high_level.py

@@ -40,7 +40,7 @@ def generate_fem_stripe_image(self, value, dtype='uint16'):
 
 
 
-class ExcaliburHighLevelTest(unittest.TestCase):
+class TestExcaliburHighLevel(unittest.TestCase):
     def create_excalibur_fem_stripe_datafile(self, fname, nframes, excalibur_data,scale):
         shape = (nframes,) + excalibur_data.fem_stripe_dimensions
         max_shape = shape#(None,) + excalibur_data.fem_stripe_dimensions

h5py/tests/hl/test_vds/test_excalibur_low_level.py

@@ -40,7 +40,7 @@ def generate_fem_stripe_image(self, value, dtype='uint16'):
 
 
 
-class ExcaliburLowLevelTest(unittest.TestCase):
+class TestExcaliburLowLevel(unittest.TestCase):
     def create_excalibur_fem_stripe_datafile(self, fname, nframes, excalibur_data,scale):
         shape = (nframes,) + excalibur_data.fem_stripe_dimensions
         max_shape = (nframes,) + excalibur_data.fem_stripe_dimensions

h5py/tests/hl/test_vds/test_percival_high_level.py

@@ -9,7 +9,7 @@
 import h5py as h5
 import tempfile
 
-class PercivalHighLevelTest(unittest.TestCase):
+class TestPercivalHighLevel(unittest.TestCase):
 
     def setUp(self):
         self.working_dir = tempfile.mkdtemp()

h5py/tests/hl/test_vds/test_percival_low_level.py

@@ -9,7 +9,7 @@
 import h5py as h5
 import tempfile
 
-class PercivalLowLevelTest(unittest.TestCase):
+class TestPercivalLowLevel(unittest.TestCase):
 
     def setUp(self):
         self.working_dir = tempfile.mkdtemp()

h5py/tests/hl/vds_tests/test_virtual_source.py

@@ -0,0 +1,138 @@
+import unittest
+import h5py as h5
+
+
+class TestVirtualSource(unittest.TestCase):
+    def test_full_slice(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[:,:,:]
+        self.assertEqual(dataset.shape,sliced.shape)
+
+    def test_full_slice_inverted(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[:,:,::-1]
+        self.assertEqual(dataset.shape,sliced.shape)
+
+    def test_subsampled_slice_inverted(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[:,:,::-2]
+        self.assertEqual((20,30,15),sliced.shape)
+
+    def test_integer_indexed(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[5,:,:]
+        self.assertEqual((1,30,30),sliced.shape)
+
+    def test_integer_single_indexed(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[5]
+        self.assertEqual((1,30,30),sliced.shape)
+
+    def test_two_integer_indexed(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[5,:,10]
+        self.assertEqual((1,30,1),sliced.shape)
+
+    def test_single_range(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[5:10,:,:]
+        self.assertEqual((5,)+dataset.shape[1:],sliced.shape)
+
+    def test_shape_calculation_positive_step(self):
+        dataset = h5.VirtualSource('test','test',(20,))
+        cmp = []
+        for i in range(5):
+            d = dataset[2:12+i:3].shape[0]
+            ref = np.arange(20)[2:12+i:3].size
+            cmp.append(ref==d)
+        self.assertEqual(5, sum(cmp))
+
+    def test_shape_calculation_positive_step_switched_start_stop(self):
+        dataset = h5.VirtualSource('test','test',(20,))
+        cmp = []
+        for i in range(5):
+            d = dataset[12+i:2:3].shape[0]
+            ref = np.arange(20)[12+i:2:3].size
+            print d,ref
+            cmp.append(ref==d)
+        self.assertEqual(5, sum(cmp))
+
+
+    def test_shape_calculation_negative_step(self):
+        dataset = h5.VirtualSource('test','test',(20,))
+        cmp = []
+        for i in range(5):
+            d = dataset[12+i:2:-3].shape[0]
+            ref = np.arange(20)[12+i:2:-3].size
+            cmp.append(ref==d)
+        self.assertEqual(5, sum(cmp))
+
+    def test_shape_calculation_negative_step_switched_start_stop(self):
+        dataset = h5.VirtualSource('test','test',(20,))
+        cmp = []
+        for i in range(5):
+            d = dataset[2:12+i:-3].shape[0]
+            ref = np.arange(20)[2:12+i:-3].size
+            cmp.append(ref==d)
+        self.assertEqual(5, sum(cmp))
+
+
+    def test_double_range(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[5:10,:,20:25]
+        self.assertEqual((5,30,5),sliced.shape)
+
+    def test_double_strided_range(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[6:12:2,:,20:26:3]
+        self.assertEqual((3,30,2,),sliced.shape)
+
+    def test_double_strided_range_inverted(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[12:6:-2,:,26:20:-3]
+        self.assertEqual((3,30,2),sliced.shape)
+
+    def test_negative_start_index(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[-10:16]
+        self.assertEqual((6,30,30),sliced.shape)
+
+    def test_negative_stop_index(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[10:-4]
+        self.assertEqual((6,30,30),sliced.shape)
+
+    def test_negative_start_and_stop_index(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[-10:-4]
+        self.assertEqual((6,30,30),sliced.shape)
+
+    def test_negative_start_and_stop_and_stride_index(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[-4:-10:-2]
+        self.assertEqual((3,30,30),sliced.shape)
+#
+    def test_ellipsis(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[...]
+        self.assertEqual(dataset.shape,sliced.shape)
+
+    def test_ellipsis_end(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[0,...]
+        self.assertEqual((1,)+dataset.shape[1:],sliced.shape)
+
+    def test_ellipsis_start(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30))
+        sliced = dataset[...,0]
+        self.assertEqual(dataset.shape[:-1]+(1,),sliced.shape)
+
+    def test_ellipsis_sandwich(self):
+        dataset = h5.VirtualSource('test','test',(20,30,30,40))
+        sliced = dataset[0,...,5]
+        self.assertEqual((1,)+dataset.shape[1:-1]+(1,),sliced.shape)
+
+
+
+if __name__ == "__main__":
+    unittest.main()

setup.py

@@ -158,7 +158,9 @@ def run(self):
   license = 'BSD',
   url = 'http://www.h5py.org',
   download_url = 'https://pypi.python.org/pypi/h5py',
-  packages = ['h5py', 'h5py._hl', 'h5py.tests', 'h5py.tests.old', 'h5py.tests.hl'],
+  packages = ['h5py', 'h5py._hl', 'h5py.tests',
+              'h5py.tests.old', 'h5py.tests.hl',
+              'h5py.tests.hl.test_vds'],
   package_data = package_data,
   ext_modules = [Extension('h5py.x',['x.c'])],  # To trick build into running build_ext
   install_requires = RUN_REQUIRES,