diff --git a/tests/icosagon/test_trainprep.py b/tests/icosagon/test_trainprep.py
index eb78859..73ec624 100644
--- a/tests/icosagon/test_trainprep.py
+++ b/tests/icosagon/test_trainprep.py
@@ -17,6 +17,7 @@ import pytest
 import numpy as np
 from itertools import chain
 from icosagon.data import RelationType
+import icosagon.trainprep
 
 
 def test_train_val_test_split_edges_01():
@@ -203,6 +204,57 @@ def test_prep_rel_two_node_types_asym_01():
     assert len(prep_rel.edges_back_neg.test) == 1
 
 
+def test_prepare_relation_type_01():
+    with pytest.raises(ValueError):
+        prepare_relation_type(None, None, True)
+
+    adj_mat = torch.rand(10, 10).round()
+    rel = RelationType('Dummy Relation', 0, 0, adj_mat, None)
+    with pytest.raises(ValueError):
+        prepare_relation_type(rel, None, True)
+
+    ratios = TrainValTest(.8, .1, .1)
+    with pytest.raises(ValueError):
+        prepare_relation_type(None, ratios, True)
+
+    _ = prepare_relation_type(rel, ratios, True)
+
+
+def test_prepare_relation_type_02(monkeypatch):
+    a = 0
+    b = 0
+    c = 0
+    def fake_prep_rel_one_node_type(*args, **kwargs):
+        nonlocal a
+        a += 1
+    def fake_prep_rel_two_node_types_sym(*args, **kwargs):
+        nonlocal b
+        b += 1
+    def fake_prep_rel_two_node_types_asym(*args, **kwargs):
+        nonlocal c
+        c += 1
+    monkeypatch.setattr(icosagon.trainprep, 'prep_rel_one_node_type',
+        fake_prep_rel_one_node_type)
+    monkeypatch.setattr(icosagon.trainprep, 'prep_rel_two_node_types_sym',
+        fake_prep_rel_two_node_types_sym)
+    monkeypatch.setattr(icosagon.trainprep, 'prep_rel_two_node_types_asym',
+        fake_prep_rel_two_node_types_asym)
+    ratios = TrainValTest(.8, .1, .1)
+    rel = RelationType('Dummy Relation', 0, 0, None, None)
+    prepare_relation_type(rel, ratios, False)
+    assert a == 1
+    rel = RelationType('Dummy Relation', 0, 0, None, None)
+    prepare_relation_type(rel, ratios, True)
+    assert a == 2
+    rel = RelationType('Dummy Relation', 0, 1, None, None)
+    prepare_relation_type(rel, ratios, True)
+    assert b == 1
+    rel = RelationType('Dummy Relation', 0, 1, None, None)
+    prepare_relation_type(rel, ratios, False)
+    assert c == 1
+    assert a == 2 and b == 1 and c == 1
+
+
 # def prepare_relation(r, ratios):
 #     adj_mat = r.adjacency_matrix
 #     adj_mat_train, edges_pos, edges_neg = prepare_adj_mat(adj_mat)