adding where clause equality method

cqlengine/query.py

@@ -540,7 +540,6 @@ class AbstractQuerySet(object):
         if self._batch:
             raise CQLEngineException("Only inserts, updates, and deletes are available in batch mode")
 
-        #TODO: check for previous query execution and return row count if it exists
         if self._result_cache is None:
             query = self._select_query()
             query.count = True

cqlengine/statements.py

@@ -50,6 +50,14 @@ class BaseClause(object):
     def __str__(self):
         return unicode(self).encode('utf-8')
 
+    def __eq__(self, other):
+        if isinstance(other, self.__class__):
+            return self.field == other.field and self.value == other.value
+        return False
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def get_context_size(self):
         """ returns the number of entries this clause will add to the query context """
         return 1
@@ -78,6 +86,11 @@ class WhereClause(BaseClause):
     def __unicode__(self):
         return u'"{}" {} :{}'.format(self.field, self.operator, self.context_id)
 
+    def __eq__(self, other):
+        if super(WhereClause, self).__eq__(other):
+            return self.operator.__class__ == other.operator.__class__
+        return False
+
     def update_context(self, ctx):
         if isinstance(self.operator, InOperator):
             ctx[str(self.context_id)] = InQuoter(self.value)

cqlengine/tests/statements/test_where_clause.py

@@ -16,3 +16,9 @@ class TestWhereClause(TestCase):
         wc.set_context_id(5)
         self.assertEqual('"a" = :5', unicode(wc))
         self.assertEqual('"a" = :5', str(wc))
+
+    def test_equality_method(self):
+        """ tests that 2 identical where clauses evaluate as == """
+        wc1 = WhereClause('a', EqualsOperator(), 'c')
+        wc2 = WhereClause('a', EqualsOperator(), 'c')
+        assert wc1 == wc2