test(net): pin that get_scrubbed keeps the vendor key out of errors (#1398)

- the message and args are masked; no request, response or chained original travels with the error; a passthrough status is returned

tests/test_get_scrubbed.py

@@ -0,0 +1,65 @@
+"""``get_scrubbed``: the vendor key must not survive into an error.
+
+FRED and Alpha Vantage authenticate with a query parameter, so requests quotes
+the key back in the text of HTTP, connection and timeout errors, and in the
+``request`` and ``response`` it attaches (#1324).
+"""
+
+from unittest import mock
+
+import pytest
+import requests
+
+from tradingagents.dataflows.net import get_scrubbed
+
+# A fabricated value in the shape of a FRED key.
+_KEY = "deadbeefdeadbeefdeadbeefdeadbeef"
+_LEAK = (
+    "HTTPSConnectionPool(host='api.stlouisfed.org', port=443): Max retries "
+    f"exceeded with url: /fred/series?series_id=DGS10&api_key={_KEY}&file_type=json"
+)
+
+
+def _response(status_code):
+    response = mock.Mock(spec=requests.Response)
+    response.status_code = status_code
+    response.raise_for_status.side_effect = requests.HTTPError(_LEAK) if status_code >= 400 else None
+    return response
+
+
+def _call(**kwargs):
+    return get_scrubbed("https://api.stlouisfed.org/fred/series",
+                        params={"api_key": _KEY}, timeout=5, secret=_KEY, **kwargs)
+
+
+@pytest.mark.unit
+@pytest.mark.parametrize("failure", [
+    {"side_effect": requests.ConnectionError(_LEAK)},
+    {"return_value": _response(500)},
+], ids=["transport", "status"])
+def test_the_key_is_masked_in_the_error(failure):
+    with mock.patch.object(requests, "get", **failure), pytest.raises(requests.RequestException) as caught:
+        _call()
+    assert _KEY not in str(caught.value) and _KEY not in repr(caught.value.args)
+    assert "api_key=***" in str(caught.value)
+
+
+@pytest.mark.unit
+def test_nothing_that_holds_the_url_travels_with_the_error():
+    """The request, the response and a chained original each carry the full URL."""
+    leaky = requests.ConnectionError(_LEAK)
+    leaky.request = mock.Mock(url=f"https://x.invalid/?api_key={_KEY}")
+    leaky.response = mock.Mock(url=f"https://x.invalid/?api_key={_KEY}")
+    with mock.patch.object(requests, "get", side_effect=leaky), pytest.raises(requests.ConnectionError) as caught:
+        _call()
+    error = caught.value
+    assert error.request is None and error.response is None
+    assert error.__cause__ is None and error.__context__ is None
+
+
+@pytest.mark.unit
+def test_a_passthrough_status_is_returned_for_the_caller():
+    response = _response(400)
+    with mock.patch.object(requests, "get", return_value=response):
+        assert _call(passthrough=(400,)) is response
+    response.raise_for_status.assert_not_called()