{
    "graph": {
        "nodes": [
            {
                "collectionName": "test.pipeline_test",
                "accessPath": {
                    "filter": {}
                },
                "embedPath": ""
            },
            {
                "collectionName": "test.A",
                "accessPath": {
                    "filter": {}
                },
                "embedPath": "a"
            },
            {
                "collectionName": "test.B",
                "accessPath": {
                    "filter": {}
                },
                "embedPath": "b"
            }
        ],
        "edges": [
            {
                "predicates": [
                    {
                        "op": "exprEq",
                        "left": {"$numberInt":"0"},
                        "right": {"$numberInt":"1"}
                    }
                ],
                "left": {"$numberInt":"0"},
                "right": {"$numberInt":"1"}
            },
            {
                "predicates": [
                    {
                        "op": "exprEq",
                        "left": {"$numberInt":"0"},
                        "right": {"$numberInt":"2"}
                    }
                ],
                "left": {"$numberInt":"0"},
                "right": {"$numberInt":"2"}
            },
            {
                "predicates": [
                    {
                        "op": "eq",
                        "left": {"$numberInt":"1"},
                        "right": {"$numberInt":"2"}
                    }
                ],
                "left": {"$numberInt":"1"},
                "right": {"$numberInt":"2"}
            }
        ]
    },
    "resolvedPaths": [
        {
            "nodeId": {"$numberInt":"0"},
            "fieldName": "bar"
        },
        {
            "nodeId": {"$numberInt":"1"},
            "fieldName": "bar"
        },
        {
            "nodeId": {"$numberInt":"2"},
            "fieldName": "bar"
        }
    ],
    "prefix": [
        {
            "$lookup": {
                "from": "A",
                "as": "a",
                "let": {
                    "bar": "$bar"
                },
                "pipeline": [
                    {
                        "$match": {
                            "$expr": {
                                "$eq": [
                                    "$bar",
                                    "$$bar"
                                ]
                            }
                        }
                    }
                ]
            }
        },
        {
            "$unwind": {
                "path": "$a"
            }
        },
        {
            "$lookup": {
                "from": "B",
                "as": "b",
                "let": {
                    "bar": "$bar"
                },
                "pipeline": [
                    {
                        "$match": {
                            "$expr": {
                                "$eq": [
                                    "$bar",
                                    "$$bar"
                                ]
                            }
                        }
                    }
                ]
            }
        },
        {
            "$unwind": {
                "path": "$b"
            }
        }
    ],
    "suffix": []
}
