def testSelfLookup(self):
    # "db.qe" is configured with QE and contains `{ "qe": "qe" }`. "qe" is encrypted.
    pipeline = [
        {
            "$lookup": {
                "from": "qe",
                "pipeline": [
                    {"$match": {"qe": "qe"}}
                ],
                "as": "matched",
            }
        },
        {"$project": {"_id": 0, "__safeContent__": 0}},
    ]
    got = self.auto_client["db"]["qe"].aggregate(pipeline).to_list()
    self.assertEqual(got, [{"qe": "qe", "matched": []}])
    # Does not match { "qe": "qe" } in sub-pipeline!

def testExplicitLookup(self):
    # "db.qe2" is configured with QE and contains `{ "qe2": "qe2" }`. "qe2" is encrypted.
    payload = self.client_encryption.encrypt(
        "qe2", algorithm=Algorithm.INDEXED, contention_factor=0, key_id=self.key_id
    )
    pipeline = [
        {
            "$lookup": {
                "from": "qe2",
                "pipeline": [
                    {"$match": {"qe2": payload}},
                ],
                "as": "matched",
            }
        },
        {"$project": {"_id": 0, "__safeContent__": 0}},
    ]
    got = self.explicit_client["db"]["qe"].aggregate(pipeline).to_list()
    self.assertEqual(got, [{"qe": "qe", "matched": []}])
    # Does not match { "qe2": "qe2" } in sub-pipeline!