Merge pull request #78 from fls-bioinformatics-core/AttributeDictiona…

…ry-reimplementation

Reimplement the AttributeDictionary class so it can be pickled

bcftbx/test/test_utils.py

@@ -6,6 +6,7 @@
 import tempfile
 import shutil
 import gzip
+import pickle
 import bcftbx.test.mock_data as mock_data
 from bcftbx.utils import *
 
@@ -53,6 +54,17 @@ def test_iter(self):
             self.assertTrue(key in ('salutation','valediction'),
                             "%s not in list" % key)
 
+    def test_can_pickle_attributedictionary(self):
+        """AttributeDictionary can be pickled
+        """
+        d = AttributeDictionary(hello="world")
+        self.assertEqual(d['hello'],"world")
+        pickled = pickle.dumps(d)
+        unpickled = pickle.loads(pickled)
+        self.assertTrue(isinstance(unpickled,AttributeDictionary))
+        self.assertEqual(unpickled['hello'],"world")
+        self.assertEqual(unpickled.hello,"world")
+
 class TestOrderedDictionary(unittest.TestCase):
     """Unit tests for the OrderedDictionary class
     """

bcftbx/utils.py

@@ -1,16 +1,14 @@
 #!/usr/bin/env python
 #
 #     utils.py: utility classes and functions shared between BCF codes
-#     Copyright (C) University of Manchester 2013-17 Peter Briggs
+#     Copyright (C) University of Manchester 2013-2018 Peter Briggs
 #
 ########################################################################
 #
 # utils.py
 #
 #########################################################################
 
-__version__ = "1.6.0"
-
 """utils
 
 Utility classes and functions shared between BCF codes.
@@ -104,7 +102,7 @@
 # General utility classes
 #######################################################################
 
-class AttributeDictionary:
+class AttributeDictionary(dict):
     """Dictionary-like object with items accessible as attributes
 
     AttributeDict provides a dictionary-like object where the value
@@ -133,25 +131,18 @@ class AttributeDictionary:
 
     """
     def __init__(self,**args):
-        self.__dict = dict(args)
+        dict.__init__(self,**args)
 
     def __getattr__(self,attr):
         try:
-            return self.__dict[attr]
+            return dict.__getattr__(self,attr)
+        except AttributeError:
+            pass
+        try:
+            return self[attr]
         except KeyError:
-            raise AttributeError, "No attribute '%s'" % attr
-
-    def __getitem__(self,key):
-        return self.__dict[key]
-
-    def __setitem__(self,key,value):
-        self.__dict[key] = value
-
-    def __iter__(self):
-        return iter(self.__dict)
-
-    def __len__(self):
-        return len(self.__dict)
+            raise AttributeError("'AttributeDictionary' has no "
+                                 "attribute '%s'" % attr)
 
 class OrderedDictionary:
     """Augumented dictionary which keeps keys in order