ERP5Catalog: Fix UnicodeDecodeError on non ascii catalog search when the inituser name is unicode

Zope4 inituser is decoded by decode('utf-8') on Zope startup and it is unicode on python2,
therefore it raises UnicodeDecodeError when searching non ascii charater on catalog.

  Traceback (most recent call last):
  File "<portal_components/test.erp5.testERP5Catalog>", line 4144, in testSearchNonAsciiWithTheInitUser
    person_module.searchFolder(title=person_title)]
  File "./erp5/product/ERP5Type/Core/Folder.py", line 452, in searchFolder
    return self.portal_catalog.searchResults(**kw)
  File "./erp5/product/ERP5Catalog/CatalogTool.py", line 819, in searchResults
    return ZCatalog.searchResults(self, sql_catalog_id=catalog_id, **kw)
  File "./erp5/product/ZSQLCatalog/ZSQLCatalog.py", line 1070, in searchResults
    return catalog.searchResults(REQUEST, **kw)
  File "./erp5/product/ZSQLCatalog/SQLCatalog.py", line 2362, in searchResults
    **kw
  File "./erp5/product/ZSQLCatalog/SQLCatalog.py", line 2326, in queryResults
    **kw
  File "./erp5/product/ZSQLCatalog/SQLCatalog.py", line 2214, in buildSQLQuery
    only_group_columns,
  File "./erp5/product/ZSQLCatalog/SQLExpression.py", line 397, in asSQLExpressionDict
    'where_expression': self.getWhereExpression(),
  File "./erp5/product/ZSQLCatalog/SQLExpression.py", line 298, in getWhereExpression
    result = self.sql_expression_list[0].getWhereExpression()
  File "./erp5/product/ZSQLCatalog/SQLExpression.py", line 303, in getWhereExpression
    result = '(%s)' % (operator.join(x.getWhereExpression() for x in self.sql_expression_list), )
  UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 25: ordinal not in range(128)

bt5/erp5_core_test/TestTemplateItem/portal_components/test.erp5.testERP5Catalog.py

@@ -4118,7 +4118,34 @@ VALUES
     # but a proper page
     self.assertIn('<title>Catalog Tool - portal_catalog', ret.getBody())
 
+  def testSearchNonAsciiWithTheInitUser(self):
+    """
+    Test non ascii search with the inituser given by the inituser-login from slapos 
+    (typically the 'zope' user)
+    """
+    person_module = self.getPersonModule()
+    person_title = 'abcdé'
+    person_module.newContent(portal_type='Person', title=person_title)
+    self.tic()
+    
+    uf = self.getPortal().acl_users
+    # The inituser is decoded by `decode('utf-8')` on Zope4 startup, and it is unicode on py2
+    # see:
+    # https://github.com/zopefoundation/AccessControl/commit/9a9c57f1c6311251a6e51a326751cf81e2810e2c
+    
+    # imitate the inituser handling
+    inituser_login = b'zope_testSearchNonAsciiWithLegacyUserFolderUser'
+    inituser_str = inituser_login.decode('utf-8')
+    self.assertTrue(isinstance(inituser_str, six.text_type))
+    uf._doAddUser(inituser_str, '', ['Member', 'Assignor'], [])
+    self.loginByUserName(inituser_str)
 
+    folder_object_list = [x.getObject().getId() for x in
+                              person_module.searchFolder(title=person_title)]
+    search_result = person_module.searchFolder(title=person_title)
+    self.assertTrue(len(search_result) > 0)
+    self.assertEqual('abcdé', search_result[0].getObject().getTitle())
+  
 class CatalogToolUpgradeSchemaTestCase(ERP5TypeTestCase):
   """Tests for "upgrade schema" feature of ERP5 Catalog.
   """

product/ERP5Catalog/CatalogTool.py

@@ -624,6 +624,8 @@ class CatalogTool (UniqueObject, ZCatalog, CMFCoreCatalogTool, ActiveObject):
       """
       user = _getAuthenticatedUser(self)
       user_str = user.getIdOrUserName()
+      if isinstance(user_str, six.text_type):
+        user_str = user_str.encode('utf-8')
       user_is_superuser = (user == system_user) or (user_str == ERP5Security.SUPER_USER)
       allowedRolesAndUsers = self._listAllowedRolesAndUsers(user)
       role_column_dict = {}