diff --git a/test_tjnetwork.py b/test_tjnetwork.py
index 039ddc8..9a8fe8a 100644
--- a/test_tjnetwork.py
+++ b/test_tjnetwork.py
@@ -1958,6 +1958,55 @@ class TestApi:
         self.leave(p)
 
 
+    def test_pattern_del(self):
+        p = 'test_pattern_del'
+        self.enter(p)
+
+        add_pattern(p, ChangeSet({'id' : 'p0', 'factors': [1.0, 2.0, 3.0]}))
+        add_junction(p, ChangeSet({'id': 'j0', 'x': 0.0, 'y': 10.0, 'elevation': 20.0, 'pattern': 'p0'}))
+        add_reservoir(p, ChangeSet({'id': 'r0', 'x': 0.0, 'y': 10.0, 'head': 20.0, 'pattern': 'p0'}))
+        add_pump(p, ChangeSet({'id': 'pump0', 'node1': 'j0', 'node2': 'r0', 'power': 0.0, 'pattern': 'p0'}))
+        set_demand(p, ChangeSet({'junction': 'j0', 'demands': [{'demand': 10.0, 'pattern': 'p0', 'category': 'x'}, {'demand': 20.0, 'pattern': 'p0', 'category': None}]}))
+        set_pump_energy(p, ChangeSet({'pump' : 'pump0', 'pattern': 'p0'}))
+        add_source(p, ChangeSet({'node': 'j0', 's_type': SOURCE_TYPE_CONCEN, 'strength': 10.0, 'pattern': 'p0' }))
+        assert is_pattern(p, 'p0')
+        assert get_junction(p, 'j0')['pattern'] == 'p0'
+        assert get_reservoir(p, 'r0')['pattern'] == 'p0'
+        assert get_pump(p, 'pump0')['pattern'] == 'p0'
+        assert get_demand(p, 'j0')['demands'] == [{'demand': 10.0, 'pattern': 'p0', 'category': 'x'}, {'demand': 20.0, 'pattern': 'p0', 'category': None}]
+        assert get_pump_energy(p, 'pump0')['pattern'] == 'p0'
+        assert get_source(p, 'j0')['pattern'] == 'p0'
+
+        delete_pattern(p, ChangeSet({'id': 'p0'}))
+        assert is_pattern(p, 'p0') == False
+        assert get_junction(p, 'j0')['pattern'] == None
+        assert get_reservoir(p, 'r0')['pattern'] == None
+        assert get_pump(p, 'pump0')['pattern'] == None
+        assert get_demand(p, 'j0')['demands'] == [{'demand': 10.0, 'pattern': None, 'category': 'x'}, {'demand': 20.0, 'pattern': None, 'category': None}]
+        assert get_pump_energy(p, 'pump0')['pattern'] == None
+        assert get_source(p, 'j0')['pattern'] == None
+
+        execute_undo(p)
+        assert is_pattern(p, 'p0')
+        assert get_junction(p, 'j0')['pattern'] == 'p0'
+        assert get_reservoir(p, 'r0')['pattern'] == 'p0'
+        assert get_pump(p, 'pump0')['pattern'] == 'p0'
+        assert get_demand(p, 'j0')['demands'] == [{'demand': 10.0, 'pattern': 'p0', 'category': 'x'}, {'demand': 20.0, 'pattern': 'p0', 'category': None}]
+        assert get_pump_energy(p, 'pump0')['pattern'] == 'p0'
+        assert get_source(p, 'j0')['pattern'] == 'p0'
+
+        execute_redo(p)
+        assert is_pattern(p, 'p0') == False
+        assert get_junction(p, 'j0')['pattern'] == None
+        assert get_reservoir(p, 'r0')['pattern'] == None
+        assert get_pump(p, 'pump0')['pattern'] == None
+        assert get_demand(p, 'j0')['demands'] == [{'demand': 10.0, 'pattern': None, 'category': 'x'}, {'demand': 20.0, 'pattern': None, 'category': None}]
+        assert get_pump_energy(p, 'pump0')['pattern'] == None
+        assert get_source(p, 'j0')['pattern'] == None
+
+        self.leave(p)
+
+
     # 12 curve