Fix pop() and slice item operations for ListFields (issue 92).

djc · djc · commit c7c7bd13265f · 2009-12-12T10:57:18.000+01:00
Thanks to melkjug for the inital patch.
diff --git a/ChangeLog.txt b/ChangeLog.txt
@@ -14,6 +14,8 @@ http://couchdb-python.googlecode.com/hg/?r=default
    instance of their `schema.Document` (issue 101).
  * `schema.ListField` proxy objects now have a more consistent (though somewhat
    slower) `count()` method (issue 91).
+ * `schema.ListField` objects now have correct behavior for slicing operations
+   and the `pop()` method (issue 92).
 
 
 Version 0.6
diff --git a/couchdb/schema.py b/couchdb/schema.py
@@ -679,6 +679,15 @@ def __getitem__(self, index):
         def __setitem__(self, index, value):
             self.list[index] = self.field._to_json(value)
 
+        def __delslice__(self, i, j):
+            del self.list[i:j]
+
+        def __getslice__(self, i, j):
+            return ListField.Proxy(self.list[i:j], self.field)
+
+        def __setslice__(self, i, j, seq):
+            self.list[i:j] = (self.field._to_json(v) for v in seq)
+
         def __contains__(self, value):
             for item in self.list:
                 if self.field._to_python(item) == value:
@@ -727,3 +736,6 @@ def insert(self, idx, *args, **kwargs):
 
         def remove(self, value):
             return self.list.remove(self.field._to_json(value))
+
+        def pop(self, *args):
+            return self.field._to_python(self.list.pop(*args))
diff --git a/couchdb/tests/schema.py b/couchdb/tests/schema.py
@@ -191,6 +191,30 @@ class Post(schema.Document):
         post = Post.load(self.db, 'test')
         assert isinstance(post.comments[0], dict)
 
+    def test_proxy_pop(self):
+        class Thing(schema.Document):
+            numbers = schema.ListField(schema.DecimalField)
+        thing = Thing()
+        thing.numbers = [Decimal('%d' % i) for i in range(3)]
+        self.assertEqual(thing.numbers.pop(), Decimal('2.0'))
+        self.assertEqual(len(thing.numbers), 2)
+        self.assertEqual(thing.numbers.pop(0), Decimal('0.0'))
+
+    def test_proxy_slices(self):
+        class Thing(schema.Document):
+            numbers = schema.ListField(schema.DecimalField)
+        thing = Thing()
+        thing.numbers = [Decimal('%d' % i) for i in range(5)]
+        ll = thing.numbers[1:3]
+        self.assertEqual(len(ll), 2)
+        self.assertEqual(ll[0], Decimal('1.0'))
+        thing.numbers[2:4] = [Decimal('%d' % i) for i in range(6, 8)]
+        self.assertEqual(thing.numbers[2], Decimal('6.0'))
+        self.assertEqual(thing.numbers[4], Decimal('4.0'))
+        self.assertEqual(len(thing.numbers), 5)
+        del thing.numbers[3:]
+        self.assertEquals(len(thing.numbers), 3)
+
 
 def suite():
     suite = unittest.TestSuite()
