Make python NULL hashable

Author: m-kuhn

python/__init__.py

@@ -55,10 +55,14 @@ def __eq__(self, other):
     def __ne__(self, other):
         return not isinstance(other, QPyNullVariant) and other is not None
 
+    def __hash__(self):
+        return 2178309
+
     QPyNullVariant.__nonzero__ = MethodType(__nonzero__, None, QPyNullVariant)
     QPyNullVariant.__repr__ = MethodType(__repr__, None, QPyNullVariant)
-    QPyNullVariant.__eq__= MethodType(__eq__, None, QPyNullVariant)
-    QPyNullVariant.__ne__= MethodType(__ne__, None, QPyNullVariant)
+    QPyNullVariant.__eq__ = MethodType(__eq__, None, QPyNullVariant)
+    QPyNullVariant.__ne__ = MethodType(__ne__, None, QPyNullVariant)
+    QPyNullVariant.__hash__ = MethodType(__hash__, None, QPyNullVariant)
 
     # define a dummy QPyNullVariant instance NULL in qgis.core
     # this is mainly used to compare against

tests/src/python/providertestbase.py

@@ -64,7 +64,7 @@ def testExtent(self):
 
     def testUnique(self):
         assert set(self.provider.uniqueValues(1)) == set([-200, 100, 200, 300, 400])
-        # assert set([u'Apple', u'Honey', u'Orange', u'Pear', NULL]) == set(self.provider.uniqueValues(2)), 'Got {}'.format(set(self.provider.uniqueValues(2)))
+        assert set([u'Apple', u'Honey', u'Orange', u'Pear', NULL]) == set(self.provider.uniqueValues(2)), 'Got {}'.format(set(self.provider.uniqueValues(2)))
 
     def testFeatureCount(self):
         assert self.provider.featureCount() == 5