ENH: key in HDFStore

Author: Chang She

pandas/io/pytables.py

@@ -167,6 +167,9 @@ def __getitem__(self, key):
     def __setitem__(self, key, value):
         self.put(key, value)
 
+    def __contains__(self, key):
+        return hasattr(self.handle.root, key)
+
     def __len__(self):
         return len(self.handle.root._v_children)
 

pandas/io/tests/test_pytables.py

@@ -65,6 +65,13 @@ def test_repr(self):
         self.store['d'] = tm.makePanel()
         repr(self.store)
 
+    def test_contains(self):
+        self.store['a'] = tm.makeTimeSeries()
+        self.store['b'] = tm.makeDataFrame()
+        self.assert_('a' in self.store)
+        self.assert_('b' in self.store)
+        self.assert_('c' not in self.store)
+
     def test_reopen_handle(self):
         self.store['a'] = tm.makeTimeSeries()
         self.store.open('w', warn=False)