[MA-1862] fixing pagination tests

lms/djangoapps/discussion_api/tests/test_pagination.py

@@ -5,7 +5,7 @@ from unittest import TestCase
 
 from django.test import RequestFactory
 
-from discussion_api.pagination import get_paginated_data
+from discussion_api.pagination import DiscussionAPIPagination
 
 
 class PaginationSerializerTest(TestCase):
@@ -16,55 +16,51 @@ class PaginationSerializerTest(TestCase):
         parameters returns the expected result
         """
         request = RequestFactory().get("/test")
-        actual = get_paginated_data(request, objects, page_num, num_pages)
-        self.assertEqual(actual, expected)
+        paginator = DiscussionAPIPagination(request, page_num, num_pages)
+        actual = paginator.get_paginated_response(objects)
+        self.assertEqual(actual.data, expected)
+
+    def get_expected_response(self, results, count, num_pages, next, previous):
+        """
+        Generates the response dictionary with passed data
+        """
+        return {
+            "pagination": {
+                "next": next,
+                "previous": previous,
+                "count": count,
+                "num_pages": num_pages,
+            },
+            "results": results
+        }
 
     def test_empty(self):
         self.do_case(
-            [], 1, 0,
-            {
-                "next": None,
-                "previous": None,
-                "results": [],
-            }
+            [], 1, 0, self.get_expected_response([], 0, 0, None, None)
         )
 
     def test_only_page(self):
         self.do_case(
-            ["foo"], 1, 1,
-            {
-                "next": None,
-                "previous": None,
-                "results": ["foo"],
-            }
+            ["foo"], 1, 1, self.get_expected_response(["foo"], 0, 1, None, None)
         )
 
     def test_first_of_many(self):
         self.do_case(
-            ["foo"], 1, 3,
-            {
-                "next": "http://testserver/test?page=2",
-                "previous": None,
-                "results": ["foo"],
-            }
+            ["foo"], 1, 3, self.get_expected_response(
+                ["foo"], 0, 3, "http://testserver/test?page=2", None
+            )
         )
 
     def test_last_of_many(self):
         self.do_case(
-            ["foo"], 3, 3,
-            {
-                "next": None,
-                "previous": "http://testserver/test?page=2",
-                "results": ["foo"],
-            }
+            ["foo"], 3, 3, self.get_expected_response(
+                ["foo"], 0, 3, None, "http://testserver/test?page=2"
+            )
         )
 
     def test_middle_of_many(self):
         self.do_case(
-            ["foo"], 2, 3,
-            {
-                "next": "http://testserver/test?page=3",
-                "previous": "http://testserver/test?page=1",
-                "results": ["foo"],
-            }
+            ["foo"], 2, 3, self.get_expected_response(
+                ["foo"], 0, 3, "http://testserver/test?page=3", "http://testserver/test?page=1"
+            )
         )