pro8 solved

Author: yyl

unit3/pro8.py

@@ -1,3 +1,7 @@
+'''
+Design and implement a class called DequeAsDoublyLinkedList that implements the Deque interface using a doubly-linked list. Select one of the approaches shown in Figure .
+'''
+
 from doublyLinkedList import DoublyLinkedList
 from opus7.container import Container
 
@@ -23,10 +27,11 @@ def dequeueHead(self):
     return self._list.extract(self._list.head.value)
 
   def enqueueTail(self, obj):
-    pass
+    self._list.append(obj)
 
   def dequeueTail(self):
-    pass
+    assert not self._list.isEmpty
+    return self._list.extract(self._list.tail.value)
 
   def __iter__(self):
     pass
@@ -35,4 +40,8 @@ def _compareTo(self, obj):
     pass
 
   def purge(self):
-    pass
+    self._list.purge()
+
+  #override
+  def getIsEmpty(self):
+    return self._list.isEmpty

unit3/test.py

@@ -91,5 +91,26 @@ def test_head(self):
     self.assertEqual(self.d.dequeueHead() , 1)
     self.assertRaises(AssertionError, self.d.dequeueHead)
 
+  def test_tail(self):
+    self.d.enqueueTail(1)
+    self.assertEqual(self.d.head.value, 1)
+    self.assertEqual(self.d.tail.value, 1)
+    self.d.enqueueTail(2)
+    self.d.enqueueTail(3)
+    self.assertEqual(self.d.head.value, 1)
+    self.assertEqual(self.d.tail.value, 3)
+    self.assertEqual(self.d.dequeueTail() , 3)
+    self.assertEqual(self.d.dequeueTail() , 2)
+    self.assertEqual(self.d.dequeueTail() , 1)
+    self.assertRaises(AssertionError, self.d.dequeueTail)
+
+  def test_purge(self):
+    self.d.enqueueHead(1)
+    self.d.enqueueHead(2)
+    self.d.enqueueHead(3)
+    self.assertFalse(self.d.isEmpty)
+    self.d.purge()
+    self.assertTrue(self.d.isEmpty)
+
 if __name__ == "__main__":
   unittest.main()