import datatlad only when running download_dataset()

neo/test/iotest/common_io_test.py

@@ -33,8 +33,13 @@
 from neo.test.rawiotest.tools import can_use_network
 from neo.test.rawiotest.common_rawio_test import repo_for_test
 from neo.utils import (download_dataset,
-    get_local_testing_data_folder, HAVE_DATALAD)
+    get_local_testing_data_folder)
 
+try:
+    import datalad
+    HAVE_DATALAD = True
+except:
+    HAVE_DATALAD = False
 
 from neo.test.iotest.tools import (cleanup_test_file,
                                    close_object_safe, create_generic_io_object,

neo/test/rawiotest/common_rawio_test.py

@@ -21,12 +21,17 @@
 import unittest
 
 from neo.utils.datasets import (download_dataset,
-    get_local_testing_data_folder, HAVE_DATALAD, default_testing_repo)
+    get_local_testing_data_folder, default_testing_repo)
 
 from neo.test.rawiotest.tools import can_use_network
 
 from neo.test.rawiotest import rawio_compliance as compliance
 
+try:
+    import datalad
+    HAVE_DATALAD = True
+except:
+    HAVE_DATALAD = False
 
 # url_for_tests = "https://portal.g-node.org/neo/" #This is the old place
 repo_for_test = default_testing_repo

neo/test/rawiotest/tools.py

@@ -5,15 +5,18 @@
 import logging
 import os
 
-from neo.utils import HAVE_DATALAD
-
 logger = logging.getLogger("neo.test")
 
 
 def can_use_network():
     """
     Return True if network access is allowed
     """
+    try:
+        import datalad
+        HAVE_DATALAD = True
+    except:
+        HAVE_DATALAD = False
     if not HAVE_DATALAD:
         return False
     if os.environ.get('NOSETESTS_NO_NETWORK', False):

neo/utils/__init__.py

@@ -5,5 +5,4 @@
 from .misc import (get_events, get_epochs, add_epoch,
     match_events, cut_block_by_epochs, cut_segment_by_epoch,
     is_block_rawio_compatible)
-from .datasets import (download_dataset,
-    get_local_testing_data_folder, HAVE_DATALAD)
+from .datasets import download_dataset, get_local_testing_data_folder

neo/utils/datasets.py

@@ -4,14 +4,6 @@
 import os
 from pathlib import Path
 
-try:
-    import datalad.api
-    from datalad.support.gitrepo import GitRepo
-
-    HAVE_DATALAD = True
-except:
-    HAVE_DATALAD = False
-
 default_testing_repo = 'https://gin.g-node.org/NeuralEnsemble/ephy_testing_data'
 
 global local_testing_data_folder
@@ -59,7 +51,8 @@ def download_dataset(repo=default_testing_repo, remote_path=None,
     local_path:
         The local path of the downloaded file or folder
     """
-    assert HAVE_DATALAD, 'You need to install datalad'
+    import datalad.api
+    from datalad.support.gitrepo import GitRepo
 
     if local_folder is None:
         global local_testing_data_folder