ERP5TypeTestCase: New method to log in, by user name instead of by id.

Because unit tests were used to choosing a login and setting a password,
making them use such method seems easier than adapting them to use the
existing "login" method, which really works by user id and not by login.

product/ERP5Type/tests/ERP5TypeTestCase.py

@@ -244,6 +244,10 @@ class ERP5TypeTestCaseMixin(ProcessingNodeTestCase, PortalTestCase):
     def login(self, user_name='ERP5TypeTestCase', quiet=0):
       """
       Most of the time, we need to login before doing anything
+
+      ATTENTION: user_name argument in this method is user's ID in
+      reality. If you want to login by user_name, use loginByUserName()
+      instead.
       """
       try:
         PortalTestCase.login(self, user_name)
@@ -251,6 +255,22 @@ class ERP5TypeTestCaseMixin(ProcessingNodeTestCase, PortalTestCase):
         self.addERP5TypeTestCaseUser()
         return PortalTestCase.login(self, user_name)
 
+    def loginByUserName(self, user_name='ERP5TypeTestCase', quiet=0):
+      """
+      Most of the time, we need to login before doing anything
+      """
+      uf = self.portal.acl_users
+      for i in range(2):
+        try:
+          user = uf.getUser(user_name)
+          if not hasattr(user, 'aq_base'):
+            user = user.__of__(uf)
+          newSecurityManager(None, user)
+          return
+        except AttributeError:
+          uf._doAddUser('ERP5TypeTestCase', '', ['Manager', 'Member', 'Assignee',
+                        'Assignor', 'Author', 'Auditor', 'Associate'], [])
+
     def changeSkin(self, skin_name):
       """
         Change current Skin