[Checkins] SVN: zc.zk/trunk/src/zc/zk/ Added __len__ to Children.

[Jim Fulton]

Log message for revision 123594:
  Added __len__ to Children.
  

Changed:
  U   zc.zk/trunk/src/zc/zk/README.txt
  U   zc.zk/trunk/src/zc/zk/__init__.py
  U   zc.zk/trunk/src/zc/zk/tests.py

-=-
Modified: zc.zk/trunk/src/zc/zk/README.txt
===================================================================
--- zc.zk/trunk/src/zc/zk/README.txt	2011-12-06 16:20:53 UTC (rev 123593)
+++ zc.zk/trunk/src/zc/zk/README.txt	2011-12-06 16:29:27 UTC (rev 123594)
@@ -95,6 +95,11 @@
     >>> sorted(addresses)
     ['192.168.0.42:8080', '192.168.0.42:8081']
 
+You can also get the number of children with ``len``:
+
+    >>> len(addresses)
+    2
+
 You can call the iterable with a callback function that is called
 whenever the list of children changes::
 
@@ -727,6 +732,13 @@
 Changes
 -------
 
+0.3.0 (2011-12-??)
+------------------
+
+- `zc.zk.Children`_ objects now have a __len__, which is mainly useful
+  for testing whether they are empty.
+
+
 0.2.0 (2011-12-05)
 ~~~~~~~~~~~~~~~~~~
 

Modified: zc.zk/trunk/src/zc/zk/__init__.py
===================================================================
--- zc.zk/trunk/src/zc/zk/__init__.py	2011-12-06 16:20:53 UTC (rev 123593)
+++ zc.zk/trunk/src/zc/zk/__init__.py	2011-12-06 16:29:27 UTC (rev 123594)
@@ -628,6 +628,9 @@
 
     event_type = zookeeper.CHILD_EVENT
 
+    def __len__(self):
+        return len(self.data)
+
 class Properties(NodeInfo, collections.Mapping):
 
     event_type = zookeeper.CHANGED_EVENT

Modified: zc.zk/trunk/src/zc/zk/tests.py
===================================================================
--- zc.zk/trunk/src/zc/zk/tests.py	2011-12-06 16:20:53 UTC (rev 123593)
+++ zc.zk/trunk/src/zc/zk/tests.py	2011-12-06 16:29:27 UTC (rev 123594)
@@ -364,12 +364,22 @@
     >>> sorted(children)
     []
 
+    >>> len(children)
+    0
+    >>> bool(children)
+    False
+
     >>> def create(path):
     ...     zk.create(path, '', zc.zk.OPEN_ACL_UNSAFE)
     >>> create('/test/a')
     >>> sorted(children)
     ['a']
 
+    >>> len(children)
+    1
+    >>> bool(children)
+    True
+
 We can register callbacks:
 
     >>> @children
@@ -396,6 +406,11 @@
     >>> create('/test/c')
     good ['a', 'b', 'c']
 
+    >>> len(children)
+    3
+    >>> bool(children)
+    True
+
 If a callback raises an error later, it is logged and the callback is
 cancelled: