feat: add join-corresponding-sums

tests/test_join_corresponding_sums_endpoint.py

@@ -0,0 +1,64 @@
+import unittest
+
+from fastapi.testclient import TestClient
+
+from app.main import create_app
+
+
+class JoinCorrespondingSumsEndpointTest(unittest.TestCase):
+    def setUp(self) -> None:
+        self.client = TestClient(create_app())
+
+    def test_creates_problem_with_matching_sums(self) -> None:
+        response = self.client.post(
+            "/math/grade_1/join_corresponding_sums",
+            json={"pair_count": 3, "seed": 1},
+        )
+
+        self.assertEqual(response.status_code, 200)
+        problem = response.json()
+
+        self.assertEqual(problem["instructions"], "Conecta.")
+        self.assertEqual(len(problem["left_expressions"]), 3)
+        self.assertEqual(len(problem["right_expressions"]), 3)
+        self.assertEqual(len(problem["answer_key"]), 3)
+
+        left_by_position = {
+            expression["position"]: expression
+            for expression in problem["left_expressions"]
+        }
+        right_by_position = {
+            expression["position"]: expression
+            for expression in problem["right_expressions"]
+        }
+
+        for expression in problem["left_expressions"] + problem["right_expressions"]:
+            self.assertEqual(
+                expression["first_addend"] + expression["second_addend"],
+                expression["total"],
+            )
+
+        for connection in problem["answer_key"]:
+            left_expression = left_by_position[connection["left_position"]]
+            right_expression = right_by_position[connection["right_position"]]
+
+            self.assertEqual(left_expression["total"], right_expression["total"])
+            self.assertEqual(left_expression["total"], connection["total"])
+            self.assertEqual(left_expression["match_id"], right_expression["match_id"])
+            self.assertEqual(left_expression["match_id"], connection["match_id"])
+
+    def test_returns_bad_request_for_impossible_ranges(self) -> None:
+        response = self.client.post(
+            "/math/grade_1/join_corresponding_sums",
+            json={"pair_count": 3, "min_sum": 2, "max_sum": 2},
+        )
+
+        self.assertEqual(response.status_code, 400)
+        self.assertEqual(
+            response.json(),
+            {"detail": "sum and addend ranges must contain enough matchable sums"},
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()