[MRG] add drive warnings

doc/whats_new.rst

@@ -21,12 +21,14 @@ Changelog
 - Add interface to modify attributes of sections in
   :func:`~hnn_core.Cell.modify_section`, by `Nick Tolley`_ in :gh:`481`
 
- - Add ability to target specific sections when adding drives or connections,
-   by `Nick Tolley`_ in :gh:`419`
+- Add ability to target specific sections when adding drives or connections,
+  by `Nick Tolley`_ in :gh:`419`
 
 - Runtime output messages now specify the trial with which each simulation time
   checkpoint belongs too, by `Ryan Thorpe`_ in :gh:`546`.
 
+- Add warning if network drives are not loaded, by `Orsolya Beatrix Kolozsvari`_ in :gh:`#516`
+
 Bug
 ~~~
 - Fix bugs in drives API to enable: rate constant argument as float; evoked drive with
@@ -340,6 +342,7 @@ People who contributed to this release (in alphabetical order):
 .. _Mattan Pelah: https://github.com/mjpelah
 .. _Mohamed A. Sherif: https://github.com/mohdsherif/
 .. _Nick Tolley: https://github.com/ntolley
+.. _Orsolya Beatrix Kolozsvari: http://github.com/orbekolo/
 .. _Ryan Thorpe: https://github.com/rythorpe
 .. _Samika Kanekar: https://github.com/samikane
 .. _Sarah Pugliese: https://bcs.mit.edu/directory/sarah-pugliese

hnn_core/dipole.py

@@ -60,6 +60,9 @@ def simulate_dipole(net, tstop, dt=0.025, n_trials=None, record_vsoma=False,
                       'net = jones_2009_model() or net = law_2021_model() to '
                       'create a predefined network from published models.',
                       UserWarning)
+    # ADD DRIVE WARNINGS HERE
+    if not net.external_drives:
+        warnings.warn('No external drives loaded', UserWarning)
 
     for drive_name, drive in net.external_drives.items():
         if 'tstop' in drive['dynamics']:

hnn_core/tests/test_drives.py

@@ -428,6 +428,10 @@ def test_add_drives():
             synaptic_delays={'L2_pyramidal': 1.},
             probability={'L2_pyramidal': 2.0})
 
+    with pytest.warns(UserWarning, match='No external drives loaded'):
+        net.clear_drives()
+        simulate_dipole(net, tstop=10)
+
 
 def test_drive_random_state():
     """Tests to check same random state always gives same spike times."""