added feature and tests for feature where students are added to waitl…

csm_web/scheduler/tests/models/test_capacity_increase_waitlist_add.py

@@ -0,0 +1,201 @@
+import pytest
+
+from scheduler.factories import (
+    CoordinatorFactory,
+    CourseFactory,
+    MentorFactory,
+    SectionFactory,
+    UserFactory,
+)
+from scheduler.models import Section, Student, WaitlistedStudent
+
+
+@pytest.fixture(name="setup_waitlist")
+def fixture_setup_waitlist(db):  # pylint: disable=unused-argument
+    """
+    Mentor, waitlisted student, enrolled student, course, and a section
+    with capacity 1 / waitlist capacity 3.
+    """
+    mentor_user, waitlisted_student_user, enrolled_student_user = (
+        UserFactory.create_batch(3)
+    )
+    course = CourseFactory.create()
+    mentor = MentorFactory.create(course=course, user=mentor_user)
+    section = SectionFactory.create(mentor=mentor, capacity=1, waitlist_capacity=3)
+    return mentor_user, waitlisted_student_user, enrolled_student_user, course, section
+
+
+@pytest.fixture(name="coord_client")
+def fixture_coord_client(client, setup_waitlist):
+    """Client logged in as a coordinator for the section's course."""
+    _, _, _, course, _ = setup_waitlist
+    coord_user = UserFactory.create()
+    CoordinatorFactory.create(user=coord_user, course=course)
+    client.force_login(coord_user)
+    return client
+
+
+def patch_section(client, section, **overrides):
+    """PATCH the section with its current values, overridden by kwargs."""
+    data = {
+        "capacity": section.capacity,
+        "description": section.description,
+        "waitlist_capacity": section.waitlist_capacity,
+        **overrides,
+    }
+    return client.patch(
+        f"/api/sections/{section.pk}/", data, content_type="application/json"
+    )
+
+
+def is_enrolled(user, section):
+    return Student.objects.filter(user=user, section=section, active=True).exists()
+
+
+def is_waitlisted(user, section):
+    return WaitlistedStudent.objects.filter(
+        user=user, section=section, active=True
+    ).exists()
+
+
+@pytest.mark.django_db
+def test_create_waitlisted_student(setup_waitlist):
+    """
+    Given we create a waitlisted student object,
+    When we call create
+    It correctly creates a waitlisted student object for the section and user.
+    """
+    mentor_user, waitlisted_student_user, _, course, section = setup_waitlist
+
+    waitlisted_student = WaitlistedStudent.objects.create(
+        user=waitlisted_student_user, course=course, section=section
+    )
+
+    assert WaitlistedStudent.objects.count() == 1
+    assert waitlisted_student.user == waitlisted_student_user
+    assert waitlisted_student.course == course
+    assert waitlisted_student.section == section
+    assert waitlisted_student.section.mentor.user == mentor_user
+    assert waitlisted_student.section.mentor.course == course
+
+    # waitlisting doesn't enroll anyone
+    assert section.students.count() == 0
+    assert section.waitlist_set.count() == 1
+
+
+@pytest.mark.django_db
+def test_add_on_capacity_increase(setup_waitlist, coord_client):
+    """
+    Given a full section with one waitlisted student,
+    When a coordinator bumps capacity by 1
+    The waitlisted student is enrolled and removed from the waitlist.
+    """
+    _, waitlisted_user, enrolled_user, course, section = setup_waitlist
+    WaitlistedStudent.objects.create(user=waitlisted_user, course=course, section=section)
+    Student.objects.create(user=enrolled_user, course=course, section=section)
+
+    assert section.current_student_count == 1
+    assert WaitlistedStudent.objects.count() == 1
+
+    response = patch_section(coord_client, section, capacity=2, description="awooga")
+    assert response.status_code in (200, 202, 204)
+
+    section = Section.objects.get(pk=section.pk)
+    assert section.capacity == 2
+    assert section.description == "awooga"
+    assert section.current_student_count == 2
+    assert is_enrolled(waitlisted_user, section)
+    assert is_enrolled(enrolled_user, section)
+    assert not is_waitlisted(waitlisted_user, section)
+
+
+@pytest.mark.django_db
+def test_capacity_increase_respects_waitlist_order(setup_waitlist, coord_client):
+    """
+    Given 3 waitlisted students and a +1 capacity bump,
+    Only the earliest waitlisted student gets enrolled.
+    """
+    _, first_user, enrolled_user, course, section = setup_waitlist
+    second_user, third_user = UserFactory.create_batch(2)
+    Student.objects.create(user=enrolled_user, course=course, section=section)
+    for user in (first_user, second_user, third_user):
+        WaitlistedStudent.objects.create(user=user, course=course, section=section)
+
+    patch_section(coord_client, section, capacity=2)
+
+    section = Section.objects.get(pk=section.pk)
+    assert is_enrolled(first_user, section)
+    assert not is_enrolled(second_user, section)
+    assert not is_enrolled(third_user, section)
+    assert is_waitlisted(second_user, section)
+    assert is_waitlisted(third_user, section)
+    assert section.current_student_count == 2
+
+
+@pytest.mark.django_db
+def test_capacity_increase_larger_than_waitlist(setup_waitlist, coord_client):
+    """
+    Given 1 waitlisted student and a +3 capacity bump,
+    The waitlist empties and the section is left under capacity (no crash).
+    """
+    _, waitlisted_user, enrolled_user, course, section = setup_waitlist
+    Student.objects.create(user=enrolled_user, course=course, section=section)
+    WaitlistedStudent.objects.create(user=waitlisted_user, course=course, section=section)
+
+    response = patch_section(coord_client, section, capacity=4)
+    assert response.status_code in (200, 202, 204)
+
+    section = Section.objects.get(pk=section.pk)
+    assert section.current_student_count == 2
+    assert section.waitlist_set.filter(active=True).count() == 0
+
+
+@pytest.mark.django_db
+def test_capacity_increase_empty_waitlist(setup_waitlist, coord_client):
+    """Bumping capacity with nobody waitlisted just updates capacity."""
+    _, _, enrolled_user, course, section = setup_waitlist
+    Student.objects.create(user=enrolled_user, course=course, section=section)
+
+    patch_section(coord_client, section, capacity=5)
+
+    section = Section.objects.get(pk=section.pk)
+    assert section.capacity == 5
+    assert section.current_student_count == 1
+
+
+@pytest.mark.django_db
+def test_capacity_decrease_does_not_drop_or_add(setup_waitlist, coord_client):
+    """
+    Lowering capacity shouldn't kick enrolled students
+    or pull anyone off the waitlist.
+    """
+    _, waitlisted_user, enrolled_user, course, section = setup_waitlist
+    section.capacity = 2
+    section.save()
+    other_user = UserFactory.create()
+    Student.objects.create(user=enrolled_user, course=course, section=section)
+    Student.objects.create(user=other_user, course=course, section=section)
+    WaitlistedStudent.objects.create(user=waitlisted_user, course=course, section=section)
+
+    patch_section(coord_client, section, capacity=1)
+
+    section = Section.objects.get(pk=section.pk)
+    assert section.current_student_count == 2
+    assert is_waitlisted(waitlisted_user, section)
+    assert not is_enrolled(waitlisted_user, section)
+
+
+@pytest.mark.django_db
+def test_non_coordinator_cannot_change_capacity(setup_waitlist, client):
+    """A student can't bump capacity to pull people off the waitlist."""
+    _, waitlisted_user, enrolled_user, course, section = setup_waitlist
+    Student.objects.create(user=enrolled_user, course=course, section=section)
+    WaitlistedStudent.objects.create(user=waitlisted_user, course=course, section=section)
+
+    client.force_login(enrolled_user)
+    response = patch_section(client, section, capacity=2)
+
+    assert response.status_code in (403, 404)
+    section = Section.objects.get(pk=section.pk)
+    assert section.capacity == 1
+    assert is_waitlisted(waitlisted_user, section)

csm_web/scheduler/views/section.py

@@ -391,6 +391,8 @@ def partial_update(self, request, pk=None):
             user=self.request.user
         ).count():
             raise PermissionDenied("Only coordinators can change section metadata")
+        old_capacity = section.capacity
+        new_capacity = request.data.get("capacity")
         serializer = self.serializer_class(
             section,
             data={
@@ -402,6 +404,10 @@ def partial_update(self, request, pk=None):
         )
         if serializer.is_valid():
             section = serializer.save()
+
+            if new_capacity > old_capacity:
+                add_from_waitlist(pk=section.pk)
+
             logger.info(
                 "<Section:Meta:Success> Updated metadata on section %s",
                 log_str(section),