fixes #1829

Author: oesteban

nipype/testing/fixtures.py

@@ -5,12 +5,17 @@
 """
 Pytest fixtures used in tests.
 """
+from __future__ import print_function, division, unicode_literals, absolute_import
+
 
 import os
 import pytest
 import numpy as np
-
 import nibabel as nb
+
+from io import open
+from builtins import str
+
 from nipype.interfaces.fsl import Info
 from nipype.interfaces.fsl.base import FSLCommand
 
@@ -25,12 +30,13 @@ def analyze_pair_image_files(outdir, filelist, shape):
 
 
 def nifti_image_files(outdir, filelist, shape):
+    if not isinstance(filelist, (list, tuple)):
+        filelist = [filelist]
+
     for f in filelist:
-        hdr = nb.Nifti1Header()
-        hdr.set_data_shape(shape)
         img = np.random.random(shape)
-        nb.save(nb.Nifti1Image(img, np.eye(4), hdr),
-                 os.path.join(outdir, f))
+        nb.Nifti1Image(img, np.eye(4), None).to_filename(
+            os.path.join(outdir, f))
 
 
 @pytest.fixture()
@@ -88,7 +94,7 @@ def create_surf_file_in_directory(request, tmpdir):
     cwd = os.getcwd()
     os.chdir(outdir)
     surf = 'lh.a.nii'
-    nifti_image_files(outdir, filelist=surf, shape=(1,100,1))
+    nifti_image_files(outdir, filelist=surf, shape=(1, 100, 1))
 
     def change_directory():
         os.chdir(cwd)