feat: add DiscountEligibilityStep pipeline step

enterprise/filters/discounts.py

@@ -0,0 +1,43 @@
+"""
+Pipeline step for excluding certain learners from course discounts.
+"""
+from openedx_filters.filters import PipelineStep
+
+# This import will be replaced with an internal path in epic 17 when
+# enterprise_support is migrated into edx-enterprise.
+try:
+    from openedx.features.enterprise_support.utils import is_enterprise_learner
+except ImportError:
+    is_enterprise_learner = None
+
+
+class DiscountEligibilityStep(PipelineStep):
+    """
+    Marks learners linked to an enterprise as ineligible for LMS-controlled discounts.
+
+    This step is intended to be registered as a pipeline step for the
+    ``org.openedx.learning.discount.eligibility.check.requested.v1`` filter.
+
+    LMS-controlled discounts (such as the first-purchase offer) are not applicable to
+    learners whose enrollment is managed by an enterprise. This step queries the
+    enterprise learner status and, if the user qualifies, sets ``is_eligible`` to
+    ``False`` so the calling code skips the discount.
+    """
+
+    def run_filter(self, user, course_key, is_eligible):  # pylint: disable=arguments-differ
+        """
+        Return ``is_eligible=False`` if the user is an enterprise learner.
+
+        Arguments:
+            user (User): the Django User being checked for discount eligibility.
+            course_key: identifies the course (passed through unchanged).
+            is_eligible (bool): the current eligibility status.
+
+        Returns:
+            dict: updated pipeline data. ``is_eligible`` is ``False`` when the user is
+            linked to an enterprise; otherwise the original ``is_eligible`` value is
+            preserved.
+        """
+        if is_enterprise_learner(user):
+            return {"user": user, "course_key": course_key, "is_eligible": False}
+        return {"user": user, "course_key": course_key, "is_eligible": is_eligible}

tests/filters/test_discounts.py

@@ -0,0 +1,79 @@
+"""
+Tests for enterprise.filters.discounts pipeline step.
+"""
+from unittest.mock import MagicMock, patch
+
+from django.test import TestCase
+
+from enterprise.filters.discounts import DiscountEligibilityStep
+
+
+class TestDiscountEligibilityStep(TestCase):
+    """
+    Tests for DiscountEligibilityStep pipeline step.
+    """
+
+    def _make_step(self):
+        return DiscountEligibilityStep(
+            "org.openedx.learning.discount.eligibility.check.requested.v1",
+            [],
+        )
+
+    def _mock_user(self):
+        user = MagicMock()
+        user.id = 42
+        return user
+
+    @patch('enterprise.filters.discounts.is_enterprise_learner', return_value=True)
+    def test_returns_ineligible_for_enterprise_learner(self, mock_is_enterprise):
+        """
+        When the user is an enterprise learner, is_eligible is set to False.
+        """
+        user = self._mock_user()
+        course_key = MagicMock()
+
+        step = self._make_step()
+        result = step.run_filter(user=user, course_key=course_key, is_eligible=True)
+
+        self.assertEqual(result, {"user": user, "course_key": course_key, "is_eligible": False})
+        mock_is_enterprise.assert_called_once_with(user)
+
+    @patch('enterprise.filters.discounts.is_enterprise_learner', return_value=False)
+    def test_returns_original_eligibility_for_non_enterprise_learner(self, mock_is_enterprise):
+        """
+        When the user is not an enterprise learner, is_eligible is passed through unchanged.
+        """
+        user = self._mock_user()
+        course_key = MagicMock()
+
+        step = self._make_step()
+        result = step.run_filter(user=user, course_key=course_key, is_eligible=True)
+
+        self.assertEqual(result, {"user": user, "course_key": course_key, "is_eligible": True})
+
+    @patch('enterprise.filters.discounts.is_enterprise_learner', return_value=False)
+    def test_passes_through_false_eligibility_unchanged(self, mock_is_enterprise):
+        """
+        When the user is not an enterprise learner and is_eligible is already False,
+        the step does not change it.
+        """
+        user = self._mock_user()
+        course_key = MagicMock()
+
+        step = self._make_step()
+        result = step.run_filter(user=user, course_key=course_key, is_eligible=False)
+
+        self.assertEqual(result["is_eligible"], False)
+
+    @patch('enterprise.filters.discounts.is_enterprise_learner', return_value=True)
+    def test_course_key_passed_through_unchanged(self, _):
+        """
+        The course_key is always returned unchanged regardless of enterprise status.
+        """
+        user = self._mock_user()
+        course_key = MagicMock()
+
+        step = self._make_step()
+        result = step.run_filter(user=user, course_key=course_key, is_eligible=True)
+
+        self.assertIs(result["course_key"], course_key)