Fixed marker & limit computation (bug 1006055)

Change-Id: I8a4a7b114b05e36024753cd02189188fd4294fc1

keystone/identity/core.py

@@ -414,18 +414,19 @@ def get_tenant_users(self, context, tenant_id, **kw):
 
     def _format_tenant_list(self, tenant_refs, **kwargs):
         marker = kwargs.get('marker')
-        page_idx = 0
+        first_index = 0
         if marker is not None:
-            for (marker_idx, tenant) in enumerate(tenant_refs):
+            for (marker_index, tenant) in enumerate(tenant_refs):
                 if tenant['id'] == marker:
                     # we start pagination after the marker
-                    page_idx = marker_idx + 1
+                    first_index = marker_index + 1
                     break
             else:
                 msg = 'Marker could not be found'
                 raise exception.ValidationError(message=msg)
 
         limit = kwargs.get('limit')
+        last_index = None
         if limit is not None:
             try:
                 limit = int(limit)
@@ -434,8 +435,9 @@ def _format_tenant_list(self, tenant_refs, **kwargs):
             except (ValueError, AssertionError):
                 msg = 'Invalid limit value'
                 raise exception.ValidationError(message=msg)
+            last_index = first_index + limit
 
-        tenant_refs = tenant_refs[page_idx:limit]
+        tenant_refs = tenant_refs[first_index:last_index]
 
         for x in tenant_refs:
             if 'enabled' not in x: