Add check

neurom/core/morphology.py

@@ -42,6 +42,7 @@
 from neurom.core.soma import make_soma
 from neurom.core.types import NeuriteIter, NeuriteType
 from neurom.utils import flatten
+from neurom.exceptions import NeuroMError
 
 
 class Section:
@@ -546,6 +547,12 @@ def __init__(self, morphio_morph, name=None, process_subtrees=False):
             name (str): an optional morphology name
             process_subtrees (bool): enable mixed tree processing if set to True
         """
+        if not isinstance(morphio_morph, (morphio.Morphology, morphio.mut.Morphology)):
+            raise NeuroMError(
+                f"Expected morphio Morphology object but got: {morphio_morph}.\n"
+                f"Use neurom.load_morphology() to load from file."
+            )
+
         self._morphio_morph = morphio_morph
 
         self.name = name if name else 'Morphology'

tests/core/test_neuron.py

@@ -29,11 +29,13 @@
 from copy import copy, deepcopy
 from pathlib import Path
 
+import pytest
 import neurom as nm
 import numpy as np
 import morphio
 from neurom.core.morphology import Morphology, graft_morphology, iter_segments
 from numpy.testing import assert_array_equal
+from neurom.exceptions import NeuroMError
 
 SWC_PATH = Path(__file__).parent.parent / 'data/swc/'
 
@@ -137,3 +139,8 @@ def test_str():
     n = nm.load_morphology(SWC_PATH / 'simple.swc')
     assert 'Morphology' in str(n)
     assert 'Section' in str(n.neurites[0].root_node)
+
+
+def test_morphology_raises_wrong_argument():
+    with pytest.raises(NeuroMError, match="Expected morphio Morphology object but got: my-path"):
+        Morphology("my-path")