latest_prices: include_expired passthrough for historical data (#2)

tests/test_client.py

@@ -71,6 +71,30 @@ def test_get_drops_none_params(monkeypatch):
     assert captured["params"] == {"commodity": "corn"}
 
 
+def test_latest_include_expired_passthrough(monkeypatch):
+    client = _reload_client(monkeypatch)
+    captured = {}
+
+    class FakeResp:
+        status_code = 200
+        text = ""
+        def json(self): return {"count": 0, "rows": []}
+
+    def fake_get(url, params=None, timeout=None, headers=None):
+        captured["params"] = dict(params or {})
+        return FakeResp()
+
+    monkeypatch.setattr(client.httpx, "get", fake_get)
+
+    # Default: not sent, so the API applies its current+future filter.
+    client.latest(commodity="corn")
+    assert "include_expired" not in captured["params"]
+
+    # Opt in: forwarded so the API returns expired months too.
+    client.latest(commodity="corn", include_expired=True)
+    assert captured["params"] == {"commodity": "corn", "include_expired": True}
+
+
 def test_futures_endpoint_params(monkeypatch):
     client = _reload_client(monkeypatch)
     captured = {}