test_dereference_refs_list_index_items_ref_mcp_like() — langchain Function Reference

Source Code

libs/core/tests/unit_tests/utils/test_json_schema.py lines 455–530

def test_dereference_refs_list_index_items_ref_mcp_like() -> None:
    """Regression test: MCP-style list index ref into array items."""
    schema = {
        "type": "object",
        "properties": {
            "body": {
                "anyOf": [
                    {"type": "string"},
                    {
                        "type": "object",
                        "properties": {
                            "Message": {
                                "type": "object",
                                "properties": {
                                    "bccRecipients": {
                                        "type": "array",
                                        "items": {
                                            "type": "object",
                                            "properties": {
                                                "emailAddress": {
                                                    "type": "object",
                                                    "properties": {
                                                        "address": {"type": "string"},
                                                        "name": {"type": "string"},
                                                    },
                                                    "required": ["address"],
                                                }
                                            },
                                        },
                                        "description": (
                                            "The Bcc: recipients for the message."
                                        ),
                                    },
                                    "ccRecipients": {
                                        "type": "array",
                                        "items": {
                                            "$ref": (
                                                "#/properties/body/anyOf/1/"
                                                "properties/Message/properties/"
                                                "bccRecipients/items"
                                            )
                                        },
                                        "description": (
                                            "The Cc: recipients for the message."
                                        ),
                                    },
                                },
                                "additionalProperties": False,
                            },
                            "SaveToSentItems": {
                                "type": ["boolean", "null"],
                                "default": False,
                            },
                        },
                        "additionalProperties": False,
                    },
                ]
            }
        },
        "required": ["body"],
        "additionalProperties": False,
    }

    resolved = dereference_refs(schema)

    message_props = resolved["properties"]["body"]["anyOf"][1]["properties"]["Message"][
        "properties"
    ]

    bcc_items = message_props["bccRecipients"]["items"]
    cc_items = message_props["ccRecipients"]["items"]

    # $ref should be fully resolved in ccRecipients.items
    assert "$ref" not in cc_items
    # And ccRecipients.items should match bccRecipients.items
    assert cc_items == bcc_items