Add test for CPE match caching

tests/nvd/cpe_match/test_api.py

@@ -399,6 +399,63 @@ async def test_cpe_matches_request_results(self):
         with self.assertRaises(Exception):
             cpe_match = await anext(it)
 
+    async def test_cpe_match_caching(self):
+        match_criteria_id = uuid4()
+        cpe_name_id = uuid4()
+
+        responses = create_cpe_match_responses(
+            match_criteria_id=match_criteria_id,
+            cpe_name_id=cpe_name_id,
+            results_per_response=3,
+        )
+        self.http_client.get.side_effect = responses
+        response_matches = [
+            [
+                match_string["match_string"]["matches"]
+                for match_string in response.json.return_value["match_strings"]
+            ]
+            for response in responses
+        ]
+
+        # Make matches of first match_string identical in each response
+        response_matches[1][0][0]["cpe_name"] = response_matches[0][0][0][
+            "cpe_name"
+        ]
+        response_matches[1][0][0]["cpe_name_id"] = response_matches[0][0][0][
+            "cpe_name_id"
+        ]
+        # Make matches of second match_string only have the same cpe_name_id
+        response_matches[1][1][0]["cpe_name_id"] = response_matches[0][1][0][
+            "cpe_name_id"
+        ]
+        # Leave matches of third match_string different from each other
+
+        it = aiter(self.api.cpe_matches(request_results=10))
+        received = [item async for item in it]
+
+        # First matches in each response of three items must be identical objects
+        self.assertIs(received[0].matches[0], received[3].matches[0])
+
+        # Second matches in each response of three items must only have same cpe_name_id
+        self.assertIsNot(received[1].matches[0], received[4].matches[0])
+        self.assertEqual(
+            received[1].matches[0].cpe_name_id,
+            received[4].matches[0].cpe_name_id,
+        )
+        self.assertNotEqual(
+            received[1].matches[0].cpe_name, received[4].matches[0].cpe_name
+        )
+
+        # Third matches in each response of three items must be different
+        self.assertIsNot(received[2].matches[0], received[5].matches[0])
+        self.assertNotEqual(
+            received[2].matches[0].cpe_name_id,
+            received[5].matches[0].cpe_name_id,
+        )
+        self.assertNotEqual(
+            received[2].matches[0].cpe_name, received[5].matches[0].cpe_name
+        )
+
     async def test_context_manager(self):
         async with self.api:
             pass