1 files changed, 24 insertions, 0 deletions
diff --git a/gaphas/tests/test_state.py b/gaphas/tests/test_state.py
new file mode 100644
index 0000000..ee779ec
--- /dev/null
+++ b/gaphas/tests/test_state.py
@@ -0,0 +1,24 @@
+import unittest
+
+from gaphas.state import reversible_pair, observed, _reverse
+
+class SList(object):
+    def __init__(self):
+        self.l = list()
+    def add(self, node, before=None):
+        if before: self.l.insert(self.l.index(before), node)
+        else: self.l.append(node)
+    add = observed(add)
+    @observed
+    def remove(self, node):
+        self.l.remove(self.l.index(node))
+
+class StateTestCase(unittest.TestCase):
+    def test_adding_pair(self):
+        """Test adding reversible pair
+        """
+        reversible_pair(SList.add, SList.remove, \
+            bind1={'before': lambda self, node: self.l[self.l.index(node)+1] })
+
+        self.assertTrue(SList.add.im_func in _reverse)
+        self.assertTrue(SList.remove.im_func in _reverse)