add test

src/tests/test_gsp.py

@@ -39,6 +39,25 @@ def test_read_latest_one_gsp(db_session, api_client):
 
     _ = [ForecastValue(**f) for f in response.json()]
 
+
+@freeze_time("2022-01-01")
+def test_read_latest_one_gsp_national(db_session, api_client):
+    """Check main solar/GB/gsp/{gsp_id}/forecast route works"""
+
+    forecasts = make_fake_forecasts(
+        gsp_ids=list(range(0, 2)), session=db_session, add_latest=True, model_name="blend"
+    )
+    db_session.add_all(forecasts)
+    db_session.commit()
+
+    app.dependency_overrides[get_session] = lambda: db_session
+
+    response = api_client.get("/v0/solar/GB/gsp/0/forecast")
+
+    assert response.status_code == 200
+
+    _ = [ForecastValue(**f) for f in response.json()]
+
 
 def test_read_latest_one_gsp_filter_creation_utc(db_session, api_client):
     """Check main solar/GB/gsp/{gsp_id}/forecast route works"""