diff --git a/test_tjnetwork.py b/test_tjnetwork.py
index b41876a..a15177b 100644
--- a/test_tjnetwork.py
+++ b/test_tjnetwork.py
@@ -1181,6 +1181,10 @@ class TestApi:
         add_junction(p, ChangeSet({'id': 'j1', 'x': 0.0, 'y': 10.0, 'elevation': 20.0}))
         assert is_junction(p, 'j1')
 
+        d = get_demand(p, 'j1')
+        assert d['junction'] == 'j1'
+        assert d['demands'] == []
+
         set_demand(p, ChangeSet({'junction': 'j1', 'demands': [{'demand': 10.0, 'pattern': None, 'category': 'x'},
                                                                {'demand': 20.0, 'pattern': None, 'category': None}]}))
         d = get_demand(p, 'j1')
@@ -1194,6 +1198,11 @@ class TestApi:
         assert ds[1]['pattern'] == None
         assert ds[1]['category'] == None
 
+        set_demand(p, ChangeSet({'junction': 'j1', 'demands': []}))
+        d = get_demand(p, 'j1')
+        assert d['junction'] == 'j1'
+        assert d['demands'] == []
+
         self.leave(p)
 
 
@@ -1263,6 +1272,12 @@ class TestApi:
         assert s['status'] == LINK_STATUS_OPEN
         assert s['setting'] == 10.0
 
+        set_status(p, ChangeSet({'link': 'p0', 'status': None, 'setting': None}))
+        s = get_status(p, 'p0')
+        assert s['link'] == 'p0'
+        assert s['status'] == None
+        assert s['setting'] == None
+
         self.leave(p)
 
 
@@ -1328,6 +1343,13 @@ class TestApi:
         assert p0['id'] == 'p0'
         assert p0['factors'] == [1.0, 2.0, 3.0]
 
+        set_pattern(p, ChangeSet({'id' : 'p0', 'factors': []}))
+
+        assert is_pattern(p, 'p0') == False
+        p0 = get_pattern(p, 'p0')
+        assert p0['id'] == 'p0'
+        assert p0['factors'] == []
+
         self.leave(p)
 
 
@@ -1377,6 +1399,13 @@ class TestApi:
         assert xys[1]['x'] == 2.0
         assert xys[1]['y'] == 1.0
 
+        set_curve(p, ChangeSet({'id' : 'c0', 'coords': []}))
+
+        assert is_curve(p, 'c0') == False
+        c0 = get_curve(p, 'c0')
+        assert c0['id'] == 'c0'
+        assert c0['coords'] == []
+
         self.leave(p)