Added util function to compute the difference between two dicts.

tests/test_api/test_utils.py

@@ -1,4 +1,6 @@
 # -*- encoding: utf-8 -*-
+from __future__ import absolute_import
+import unittest
 
 from bson import ObjectId
 from pillar.tests import AbstractPillarTest
@@ -28,3 +30,57 @@ class Str2idTest(AbstractPillarTest):
         unhappy('')
         unhappy(u'')
         unhappy(None)
+
+
+class DocDiffTest(unittest.TestCase):
+    def test_no_diff_simple(self):
+        from pillar.api.utils import doc_diff
+        diff = doc_diff({'a': 'b', 3: 42},
+                        {'a': 'b', 3: 42})
+
+        self.assertEqual([], list(diff))
+
+    def test_no_diff_privates(self):
+        from pillar.api.utils import doc_diff
+        diff = doc_diff({'a': 'b', 3: 42, '_updated': 5133},
+                        {'a': 'b', 3: 42, '_updated': 42})
+
+        self.assertEqual([], list(diff))
+
+    def test_diff_values_simple(self):
+        from pillar.api.utils import doc_diff
+        diff = doc_diff({'a': 'b', 3: 42},
+                        {'a': 'b', 3: 513})
+
+        self.assertEqual([(3, 42, 513)], list(diff))
+
+    def test_diff_keys_simple(self):
+        from pillar.api.utils import doc_diff, DoesNotExist
+        diff = doc_diff({'a': 'b', 3: 42},
+                        {'a': 'b', 2: 42})
+
+        self.assertEqual({(3, 42, DoesNotExist), (2, DoesNotExist, 42)}, set(diff))
+
+    def test_no_diff_nested(self):
+        from pillar.api.utils import doc_diff
+        diff = doc_diff({'a': 'b', 'props': {'status': u'todo', 'notes': u'jemoeder'}},
+                        {'a': 'b', 'props': {'status': u'todo', 'notes': u'jemoeder'}})
+
+        self.assertEqual([], list(diff))
+
+    def test_diff_values_nested(self):
+        from pillar.api.utils import doc_diff
+        diff = doc_diff({'a': 'b', 'props': {'status': u'todo', 'notes': u'jemoeder'}},
+                        {'a': 'c', 'props': {'status': u'done', 'notes': u'jemoeder'}})
+
+        self.assertEqual({('a', 'b', 'c'), ('props.status', u'todo', u'done')},
+                         set(diff))
+
+    def test_diff_keys_nested(self):
+        from pillar.api.utils import doc_diff, DoesNotExist
+        diff = doc_diff({'a': 'b', 'props': {'status1': u'todo', 'notes': u'jemoeder'}},
+                        {'a': 'b', 'props': {'status2': u'todo', 'notes': u'jemoeder'}})
+
+        self.assertEqual({('props.status1', u'todo', DoesNotExist),
+                          ('props.status2', DoesNotExist, u'todo')},
+                         set(diff))