diff --git a/swh/storage/tests/__init__.py b/swh/storage/tests/__init__.py
index 98728e54..52366435 100644
--- a/swh/storage/tests/__init__.py
+++ b/swh/storage/tests/__init__.py
@@ -1,56 +1,54 @@
 # Copyright (C) 2015-2018  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 from os import path
 import swh.storage
 
 from hypothesis.strategies import (binary, composite, lists)
 
 from swh.model.hashutil import MultiHash
 
 
 SQL_DIR = path.join(path.dirname(swh.storage.__file__), 'sql')
 
 
 def gen_raw_content():
     """Generate raw content binary.
 
     """
     return binary(min_size=20, max_size=100)
 
 
 @composite
 def gen_contents(draw, *, min_size=0, max_size=100):
     """Generate valid and consistent content.
 
     Context: Test purposes
 
     Args:
         **draw**: Used by hypothesis to generate data
         **min_size** (int): Minimal number of elements to generate
                             (default: 0)
         **max_size** (int): Maximal number of elements to generate
                             (default: 100)
 
     Returns:
         [dict] representing contents. The list's size is between
         [min_size:max_size].
 
     """
     raw_contents = draw(lists(
         gen_raw_content(), min_size=min_size, max_size=max_size))
 
     contents = []
     for raw_content in raw_contents:
-        content = {
+        contents.append({
             'data': raw_content,
             'length': len(raw_content),
             'status': 'visible',
-        }
-        hashes = MultiHash.from_data(raw_content).digest()
-        content.update(hashes)
-        contents.append(content)
+            **MultiHash.from_data(raw_content).digest()
+        })
 
     return contents