From b4c66f57d20a7d28b73b14f5c0b09b16038a8e71 Mon Sep 17 00:00:00 2001
From: stephensanchez <steve@edx.org>
Date: Wed, 28 Jan 2015 22:11:50 +0000
Subject: [PATCH] Fix the redemption codes to allow upgrading course modes.

---
 .../shoppingcart/tests/test_views.py          | 27 +++++++++++++++++++
 lms/djangoapps/shoppingcart/views.py          | 26 ++++++++++++++++--
 2 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/lms/djangoapps/shoppingcart/tests/test_views.py b/lms/djangoapps/shoppingcart/tests/test_views.py
index d5402724ee..a729f18e05 100644
--- a/lms/djangoapps/shoppingcart/tests/test_views.py
+++ b/lms/djangoapps/shoppingcart/tests/test_views.py
@@ -550,6 +550,33 @@ class ShoppingCartViewsTests(ModuleStoreTestCase):
         self.assertEqual(resp.status_code, 400)
         self.assertIn("Oops! The code '{0}' you entered is either invalid or expired".format(self.reg_code), resp.content)
 
+    def test_upgrade_from_valid_reg_code(self):
+        """Use a valid registration code to upgrade from honor to verified mode. """
+        # Ensure the course has a verified mode
+        course_key = self.course_key.to_deprecated_string()
+        self._add_course_mode(mode_slug='verified')
+        self.add_reg_code(course_key, mode_slug='verified')
+
+        # Enroll as honor in the course with the current user.
+        CourseEnrollment.enroll(self.user, self.course_key)
+        self.login_user()
+        current_enrollment, __ = CourseEnrollment.enrollment_mode_for_user(self.user, self.course_key)
+        self.assertEquals('honor', current_enrollment)
+
+        redeem_url = reverse('register_code_redemption', args=[self.reg_code])
+        response = self.client.get(redeem_url)
+        self.assertEquals(response.status_code, 200)
+        # check button text
+        self.assertTrue('Activate Course Enrollment' in response.content)
+
+        #now activate the user by enrolling him/her to the course
+        response = self.client.post(redeem_url)
+        self.assertEquals(response.status_code, 200)
+
+        # Once upgraded, should be "verified"
+        current_enrollment, __ = CourseEnrollment.enrollment_mode_for_user(self.user, self.course_key)
+        self.assertEquals('verified', current_enrollment)
+
     @patch('shoppingcart.views.log.debug')
     def test_non_existing_coupon_redemption_on_removing_item(self, debug_log):
 
diff --git a/lms/djangoapps/shoppingcart/views.py b/lms/djangoapps/shoppingcart/views.py
index 8ed9666922..c4173510ae 100644
--- a/lms/djangoapps/shoppingcart/views.py
+++ b/lms/djangoapps/shoppingcart/views.py
@@ -24,7 +24,6 @@ from opaque_keys.edx.locations import SlashSeparatedCourseKey
 from opaque_keys.edx.locator import CourseLocator
 from opaque_keys import InvalidKeyError
 from courseware.courses import get_course_by_id
-from courseware.views import registered_for_course
 from config_models.decorators import require_config
 from shoppingcart.reports import RefundReport, ItemizedPurchaseReport, UniversityRevenueShareReport, CertificateStatusReport
 from student.models import CourseEnrollment, EnrollmentClosedError, CourseFullError, \
@@ -345,7 +344,7 @@ def register_code_redemption(request, registration_code):
             'reg_code': registration_code,
             'site_name': site_name,
             'course': course,
-            'registered_for_course': registered_for_course(course, request.user)
+            'registered_for_course': not _is_enrollment_code_an_update(course, request.user, course_registration)
         }
         return render_to_response(template_to_render, context)
     elif request.method == "POST":
@@ -401,6 +400,29 @@ def register_code_redemption(request, registration_code):
         return render_to_response(template_to_render, context)
 
 
+def _is_enrollment_code_an_update(course, user, redemption_code):
+    """Checks to see if the user's enrollment can be updated by the code.
+
+    Check to see if the enrollment code and the user's enrollment match. If they are different, the code
+    may be used to alter the enrollment of the user. If the enrollment is inactive, will return True, since
+    the user may use the code to re-activate an enrollment as well.
+
+    Enrollment redemption codes must be associated with a paid course mode. If the current enrollment is a
+    different mode then the mode associated with the code, use of the code can be considered an upgrade.
+
+    Args:
+        course (CourseDescriptor): The course to check for enrollment.
+        user (User): The user that will be using the redemption code.
+        redemption_code (CourseRegistrationCode): The redemption code that will be used to update the user's enrollment.
+
+    Returns:
+        True if the redemption code can be used to upgrade the enrollment, or re-activate it.
+
+    """
+    enrollment_mode, is_active = CourseEnrollment.enrollment_mode_for_user(user, course.id)
+    return not is_active or enrollment_mode != redemption_code.mode_slug
+
+
 def use_registration_code(course_reg, user):
     """
     This method utilize course registration code.