From 6088a926cc0697094c1bd6ae095581895fcc4563 Mon Sep 17 00:00:00 2001
From: Victor Shnayder <victor@mitx.mit.edu>
Date: Sun, 20 Jan 2013 17:35:03 -0500
Subject: [PATCH] Add showanswer="past_due" and tests

---
 common/lib/xmodule/xmodule/capa_module.py     | 35 ++++++++------
 .../xmodule/xmodule/tests/test_capa_module.py | 47 ++++++++++++++++++-
 2 files changed, 65 insertions(+), 17 deletions(-)

diff --git a/common/lib/xmodule/xmodule/capa_module.py b/common/lib/xmodule/xmodule/capa_module.py
index f33da6e3a4..6d258e61ed 100644
--- a/common/lib/xmodule/xmodule/capa_module.py
+++ b/common/lib/xmodule/xmodule/capa_module.py
@@ -389,38 +389,43 @@ class CapaModule(XModule):
             })
         return json.dumps(d, cls=ComplexEncoder)
 
+    def is_past_due(self):
+        """
+        Is it now past this problem's due date, including grace period?
+        """
+        return (self.close_date is not None and
+                datetime.datetime.utcnow() > self.close_date)
+
     def closed(self):
         ''' Is the student still allowed to submit answers? '''
         if self.attempts == self.max_attempts:
             return True
-        if self.close_date is not None and datetime.datetime.utcnow() > self.close_date:
+        if self.is_past_due():
             return True
 
         return False
 
     def answer_available(self):
-        ''' Is the user allowed to see an answer?
+        '''
+        Is the user allowed to see an answer?
         '''
         if self.show_answer == '':
             return False
-
-        if self.show_answer == "never":
+        elif self.show_answer == "never":
             return False
-
-        # Admins can see the answer, unless the problem explicitly prevents it
-        if self.system.user_is_staff:
+        elif self.system.user_is_staff:
+            # This i after the 'never' check because admins can see the answer
+            # unless the problem explicitly prevents it
             return True
-
-        if self.show_answer == 'attempted':
+        elif self.show_answer == 'attempted':
             return self.attempts > 0
-
-        if self.show_answer == 'answered':
+        elif self.show_answer == 'answered':
             return self.lcp.done
-
-        if self.show_answer == 'closed':
+        elif self.show_answer == 'closed':
             return self.closed()
-
-        if self.show_answer == 'always':
+        elif self.show_answer == 'past_due':
+            return self.is_past_due()
+        elif self.show_answer == 'always':
             return True
 
         return False
diff --git a/common/lib/xmodule/xmodule/tests/test_capa_module.py b/common/lib/xmodule/xmodule/tests/test_capa_module.py
index 506c7faf9f..e8f639e3c9 100644
--- a/common/lib/xmodule/xmodule/tests/test_capa_module.py
+++ b/common/lib/xmodule/xmodule/tests/test_capa_module.py
@@ -138,10 +138,11 @@ class CapaModuleTest(unittest.TestCase):
 
     def test_showanswer_closed(self):
 
-        # can see after attempts used up
+        # can see after attempts used up, even with due date in the future
         used_all_attempts = CapaFactory.create(showanswer='closed',
                                                max_attempts="1",
-                                               attempts="1")
+                                               attempts="1",
+                                               due=self.tomorrow_str)
         self.assertTrue(used_all_attempts.answer_available())
 
 
@@ -152,6 +153,7 @@ class CapaModuleTest(unittest.TestCase):
                                                due=self.yesterday_str)
         self.assertTrue(after_due_date.answer_available())
 
+
         # can't see because attempts left
         attempts_left_open = CapaFactory.create(showanswer='closed',
                                                max_attempts="1",
@@ -169,4 +171,45 @@ class CapaModuleTest(unittest.TestCase):
 
 
 
+    def test_showanswer_past_due(self):
+        """
+        With showanswer="past_due" should only show answer after the problem is closed
+        for everyone--e.g. after due date + grace period.
+        """
+
+        # can see after attempts used up, even with due date in the future
+        used_all_attempts = CapaFactory.create(showanswer='past_due',
+                                               max_attempts="1",
+                                               attempts="1",
+                                               due=self.tomorrow_str)
+        self.assertFalse(used_all_attempts.answer_available())
+
+
+        # can see after due date
+        past_due_date = CapaFactory.create(showanswer='past_due',
+                                               max_attempts="1",
+                                               attempts="0",
+                                               due=self.yesterday_str)
+        self.assertTrue(past_due_date.answer_available())
+
+
+        # can't see because attempts left
+        attempts_left_open = CapaFactory.create(showanswer='past_due',
+                                               max_attempts="1",
+                                               attempts="0",
+                                               due=self.tomorrow_str)
+        self.assertFalse(attempts_left_open.answer_available())
+
+        # Can't see because grace period hasn't expired, even though have no more
+        # attempts.
+        still_in_grace = CapaFactory.create(showanswer='past_due',
+                                            max_attempts="1",
+                                            attempts="1",
+                                            due=self.yesterday_str,
+                                            graceperiod=self.two_day_delta_str)
+        self.assertFalse(still_in_grace.answer_available())
+
+
+
+