diff --git a/swh/web/ui/tests/test_service.py b/swh/web/ui/tests/test_service.py
index f1d6f38f..96816017 100644
--- a/swh/web/ui/tests/test_service.py
+++ b/swh/web/ui/tests/test_service.py
@@ -1,110 +1,128 @@
 # Copyright (C) 2015  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU Affero General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import unittest
 
 from nose.tools import istest
 
 from unittest.mock import MagicMock
 
+from swh.core import hashutil
 from swh.storage.api.client import RemoteStorage as Storage
 from swh.web.ui import service, controller
 
 
 # Because the Storage's __init__ function does side effect at startup...
 class RemoteStorageAdapter(Storage):
     def __init__(self, base_url):
         self.base_url = base_url
 
 
 class ServiceTestCase(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         cls.storage = RemoteStorageAdapter('http://localhost:5000/')  # Mock
 
         # inject the mock data
         conf = {'api_backend': 'https://somewhere.org:4321',
                 'storage': cls.storage}
 
         controller.app.config['TESTING'] = True
         controller.app.config.update({'conf': conf})
         cls.app = controller.app.test_client()
 
     @istest
     def lookup_hash_does_not_exist(self):
         # given
         self.storage.content_exist = MagicMock(return_value=False)
 
         # when
         actual_lookup = service.lookup_hash(
             'sha1:123caf10e9535160d90e874b45aa426de762f19f')
 
+        # then
         self.assertFalse(actual_lookup)
 
+        # check the function has been called with parameters
+        self.storage.content_exist.assert_called_with({
+            'sha1':
+            hashutil.hex_to_hash('123caf10e9535160d90e874b45aa426de762f19f')})
+
     @istest
     def lookup_hash_exist(self):
         # given
         self.storage.content_exist = MagicMock(return_value=True)
 
         # when
         actual_lookup = service.lookup_hash(
-            'sha1:123caf10e9535160d90e874b45aa426de762f19f')
+            'sha1:456caf10e9535160d90e874b45aa426de762f19f')
 
+        # then
         self.assertTrue(actual_lookup)
 
+        self.storage.content_exist.assert_called_with({
+            'sha1':
+            hashutil.hex_to_hash('456caf10e9535160d90e874b45aa426de762f19f')})
+
     @istest
     def lookup_hash_origin(self):
         # given
         self.storage.content_find_occurrence = MagicMock(return_value={
             'origin_type': 'sftp',
             'origin_url': 'sftp://ftp.gnu.org/gnu/octave',
             'branch': 'octavio-3.4.0.tar.gz',
             'revision': b'\xb0L\xaf\x10\xe9SQ`\xd9\x0e\x87KE\xaaBm\xe7b\xf1\x9f',  # noqa
             'path': b'octavio-3.4.0/doc/interpreter/octave.html/doc_002dS_005fISREG.html'  # noqa
         })
         expected_origin = {
             'origin_type': 'sftp',
             'origin_url': 'sftp://ftp.gnu.org/gnu/octave',
             'branch': 'octavio-3.4.0.tar.gz',
             'revision': 'b04caf10e9535160d90e874b45aa426de762f19f',
             'path': 'octavio-3.4.0/doc/interpreter/octave.html/doc'
                     '_002dS_005fISREG.html'
         }
 
         # when
         actual_origin = service.lookup_hash_origin(
             'sha1_git:456caf10e9535160d90e874b45aa426de762f19f')
 
         # then
         self.assertEqual(actual_origin, expected_origin)
 
+        self.storage.content_find_occurrence.assert_called_with(
+            {'sha1_git':
+             hashutil.hex_to_hash('456caf10e9535160d90e874b45aa426de762f19f')})
+
     @istest
     def stat_counters(self):
         # given
         input_stats = {
             "content": 1770830,
             "directory": 211683,
             "directory_entry_dir": 209167,
             "directory_entry_file": 1807094,
             "directory_entry_rev": 0,
             "entity": 0,
             "entity_history": 0,
             "occurrence": 0,
             "occurrence_history": 19600,
             "origin": 1096,
             "person": 0,
             "release": 8584,
             "revision": 7792,
             "revision_history": 0,
             "skipped_content": 0
         }
         self.storage.stat_counters = MagicMock(return_value=input_stats)
 
         # when
         actual_stats = service.stat_counters()
 
         # then
         expected_stats = input_stats
         self.assertEqual(actual_stats, expected_stats)
+
+        self.storage.stat_counters.assert_called_with()