ZSQLCatalog: Do not distinguish between int, long and floats in lists.

Do not require caller to cast between these types when they can all make
sense to appear in the same list.

product/ZSQLCatalog/SearchKey/SearchKey.py

@@ -73,6 +73,8 @@ operator_value_deprocessor_dict = {
   'like': deprocessLikeValue
 }
 
+numeric_type_set = (long, float) # get mapped to int, so do not mention it
+
 class SearchKey(object):
 
   implements(ISearchKey)
@@ -266,16 +268,21 @@ class SearchKey(object):
     # Cast to list
     if isinstance(search_value, list_type_list):
       # Check list content (not empty, homogenous)
-      iter_search_value = iter(search_value)
+      # Note: neither is strictly required, but it helps spotting easy mistakes.
+      klass_set = {
+        int if x.__class__ in numeric_type_set else x.__class__
+        for x in search_value
+      }
       try:
-        reference_class = iter_search_value.next().__class__
-      except StopIteration:
-        raise ValueError, 'Value cannot be an empty list/tuple: %r' % \
-                          (search_value, )
-      for x in iter_search_value:
-        if x.__class__ != reference_class:
-          raise TypeError, 'List elements must be of the same class: %r' % \
-                           (search_value, )
+        reference_class, = klass_set
+      except ValueError:
+        if search_value:
+          raise TypeError(
+            'List elements must be of the same class: %r' % (search_value, )
+          )
+        raise ValueError(
+          'Value cannot be an empty list/tuple: %r' % (search_value, )
+        )
     else:
       assert logical_operator is None
       if isinstance(search_value, dict):