--- a/app/soc/modules/ghop/views/helper/access.py	Fri Nov 13 19:02:38 2009 +0100
+++ b/app/soc/modules/ghop/views/helper/access.py	Sat Nov 14 17:22:44 2009 +0100
@@ -37,6 +37,7 @@
 from soc.modules.ghop.logic.models import mentor as ghop_mentor_logic
 from soc.modules.ghop.logic.models import org_admin as ghop_org_admin_logic
 from soc.modules.ghop.logic.models import program as ghop_program_logic
+from soc.modules.ghop.logic.models.student import logic as ghop_student_logic
 from soc.modules.ghop.logic.models import task as ghop_task_logic
 
 
@@ -66,6 +67,9 @@
 DEF_SIGN_UP_AS_OA_MENTOR_MSG = ugettext(
     'You first need to sign up as an Org Admin or a Mentor.')
 
+DEF_NO_TASKS_ASSIGNED = ugettext(
+    'There are no tasks which have been assigned to you.')
+
 
 class GHOPChecker(access.Checker):
   """See soc.views.helper.access.Checker.
@@ -267,3 +271,33 @@
     # no completed tasks found, access denied
     raise out_of_band.AccessViolation(
         message_fmt=DEF_CANT_REGISTER)
+
+  def checkCanOpenTaskList(self, django_args):
+    """Checks if the current user is allowed to see a list of his tasks.
+
+    Args:
+      django_args: a dictionary with django's arguments
+
+    Raises:
+      AccessViolationResponse:
+        - if the user is not registered as a student; and
+        - if the user has not claimed a single task
+    """
+
+    try:
+      return self.checkHasActiveRoleForScope(django_args, ghop_student_logic)
+    except out_of_band.Error:
+      pass
+
+    program = ghop_program_logic.logic.getFromKeyNameOr404(
+        django_args['scope_path'])
+
+    filter = {
+        'user': self.user,
+        'program': program,
+        'status': ['ClaimRequested', 'Claimed', 'ActionNeeded', 'NeedsWork',
+            'AwaitingRegistration', 'NeedsReview']
+        }
+
+    if not ghop_task_logic.logic.getForFields(filter, unique=True):
+      raise out_of_band.AccessViolation(message_fmt=DEF_NO_TASKS_ASSIGNED)