ENH: Improved test coverage.

Author: MarcCote

nibabel/streamlines/tests/test_array_sequence.py

@@ -152,6 +152,11 @@ def test_arraysequence_append(self):
         seq.append(element)
         check_arr_seq(seq, [element])
 
+        # Append an empty array.
+        seq = SEQ_DATA['seq'].copy()  # Copy because of in-place modification.
+        seq.append([])
+        check_arr_seq(seq, SEQ_DATA['seq'])
+
         # Append an element with different shape.
         element = generate_data(nb_arrays=1,
                                 common_shape=SEQ_DATA['seq'].common_shape*2,

nibabel/streamlines/tests/test_tractogram.py

@@ -13,6 +13,7 @@
 from six.moves import zip
 
 from .. import tractogram as module_tractogram
+from ..tractogram import is_data_dict, is_lazy_dict
 from ..tractogram import TractogramItem, Tractogram, LazyTractogram
 from ..tractogram import PerArrayDict, PerArraySequenceDict, LazyDict
 
@@ -406,14 +407,20 @@ def test_extend(self):
 class TestLazyDict(unittest.TestCase):
 
     def test_lazydict_creation(self):
-        data_dict = LazyDict(DATA['data_per_streamline_func'])
-        assert_equal(data_dict.keys(), DATA['data_per_streamline_func'].keys())
-        for k in data_dict.keys():
-            assert_array_equal(list(data_dict[k]),
-                               list(DATA['data_per_streamline'][k]))
+        # Different ways of creating LazyDict
+        lazy_dicts = []
+        lazy_dicts += [LazyDict(DATA['data_per_streamline_func'])]
+        lazy_dicts += [LazyDict(**DATA['data_per_streamline_func'])]
 
-        assert_equal(len(data_dict),
-                     len(DATA['data_per_streamline_func']))
+        for data_dict in lazy_dicts:
+            assert_true(is_lazy_dict(data_dict))
+            assert_equal(data_dict.keys(), DATA['data_per_streamline_func'].keys())
+            for k in data_dict.keys():
+                assert_array_equal(list(data_dict[k]),
+                                   list(DATA['data_per_streamline'][k]))
+
+            assert_equal(len(data_dict),
+                         len(DATA['data_per_streamline_func']))
 
 
 class TestTractogramItem(unittest.TestCase):
@@ -470,6 +477,9 @@ def test_tractogram_creation(self):
                          DATA['data_per_streamline'],
                          DATA['data_per_point'])
 
+        assert_true(is_data_dict(tractogram.data_per_streamline))
+        assert_true(is_data_dict(tractogram.data_per_point))
+
         # Create a tractogram from another tractogram attributes.
         tractogram2 = Tractogram(tractogram.streamlines,
                                  tractogram.data_per_streamline,
@@ -795,6 +805,9 @@ def test_lazy_tractogram_creation(self):
                                     DATA['data_per_streamline_func'],
                                     DATA['data_per_point_func'])
 
+        assert_true(is_lazy_dict(tractogram.data_per_streamline))
+        assert_true(is_lazy_dict(tractogram.data_per_point))
+
         [t for t in tractogram]  # Force iteration through tractogram.
         assert_equal(len(tractogram), len(DATA['streamlines']))
 
@@ -910,6 +923,22 @@ def test_lazy_tractogram_apply_affine(self):
         tractogram.affine_to_rasmm = None
         assert_raises(ValueError, tractogram.to_world)
 
+        # But calling apply_affine when affine_to_rasmm is None should work.
+        tractogram = DATA['lazy_tractogram'].copy()
+        tractogram.affine_to_rasmm = None
+        transformed_tractogram = tractogram.apply_affine(affine)
+        assert_array_equal(transformed_tractogram._affine_to_apply, affine)
+        assert_true(transformed_tractogram.affine_to_rasmm is None)
+        check_tractogram(transformed_tractogram,
+                         streamlines=[s*scaling for s in DATA['streamlines']],
+                         data_per_streamline=DATA['data_per_streamline'],
+                         data_per_point=DATA['data_per_point'])
+
+        # Calling apply_affine with lazy=False should fail for LazyTractogram.
+        tractogram = DATA['lazy_tractogram'].copy()
+        assert_raises(ValueError, tractogram.apply_affine,
+                      affine=np.eye(4), lazy=False)
+
     def test_tractogram_to_world(self):
         tractogram = DATA['lazy_tractogram'].copy()
         affine = np.random.RandomState(1234).randn(4, 4)

nibabel/streamlines/tractogram.py

@@ -77,7 +77,7 @@ class PerArrayDict(SliceableDataDict):
 
     This container behaves like a standard dictionary but extends key access to
     allow keys for key access to be indices slicing into the contained ndarray
-    values.  The elements must also be ndarrays.
+    values. The elements must also be ndarrays.
 
     In addition, it makes sure the amount of data contained in those ndarrays
     matches the number of streamlines given at the instantiation of this
@@ -200,9 +200,6 @@ def __init__(self, *args, **kwargs):
                 self.update(**args[0].store)  # Copy the generator functions.
                 return
 
-            if isinstance(args[0], SliceableDataDict):
-                self.update(**args[0])
-
         self.update(dict(*args, **kwargs))
 
     def __getitem__(self, key):