test_openai_tool_parser.py

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project

import json

import pytest
from openai_harmony import (Conversation, DeveloperContent,
                            HarmonyEncodingName, Message, Role, SystemContent,
                            load_harmony_encoding)

from vllm.entrypoints.openai.protocol import FunctionCall, ToolCall
from vllm.entrypoints.openai.tool_parsers import OpenAIToolParser
from vllm.transformers_utils.tokenizer import get_tokenizer

MODEL = "gpt2"


@pytest.fixture(scope="module")
def openai_tokenizer():
    # The parser does not use the tokenizer, but the constructor requires it.
    return get_tokenizer(MODEL)


@pytest.fixture
def openai_tool_parser(openai_tokenizer):
    return OpenAIToolParser(openai_tokenizer)


@pytest.fixture(scope="module")
def harmony_encoding():
    return load_harmony_encoding(HarmonyEncodingName.HARMONY_GPT_OSS)


def assert_tool_calls(
    actual_tool_calls: list[ToolCall],
    expected_tool_calls: list[ToolCall],
):
    assert len(actual_tool_calls) == len(expected_tool_calls)

    for actual_tool_call, expected_tool_call in zip(actual_tool_calls,
                                                    expected_tool_calls):
        assert isinstance(actual_tool_call.id, str)
        assert len(actual_tool_call.id) > 16  # Default from protocol.py
        assert actual_tool_call.type == "function"
        assert actual_tool_call.function == expected_tool_call.function


def test_extract_tool_calls_no_tools(openai_tool_parser, harmony_encoding):
    convo = Conversation.from_messages([
        Message.from_role_and_content(
            Role.SYSTEM,
            SystemContent.new(),
        ),
        Message.from_role_and_content(
            Role.DEVELOPER,
            DeveloperContent.new().with_instructions("Talk like a pirate!")),
        Message.from_role_and_content(Role.USER, "Arrr, how be you?"),
        Message.from_role_and_content(Role.ASSISTANT,
                                      "This is a test").with_channel("final")
    ])
    token_ids = harmony_encoding.render_conversation_for_completion(
        convo, Role.ASSISTANT)
    extracted_info = openai_tool_parser.extract_tool_calls(
        "",
        request=None,
        token_ids=token_ids,
    )
    assert not extracted_info.tools_called
    assert extracted_info.tool_calls == []
    assert extracted_info.content == "This is a test"


def test_extract_tool_calls_single_tool(openai_tool_parser, harmony_encoding):
    convo = Conversation.from_messages([
        Message.from_role_and_content(Role.USER,
                                      "What is the weather in Tokyo?"),
        Message.from_role_and_content(
            Role.ASSISTANT,
            'User asks: "What is the weather in Tokyo?" We need to use get_current_weather tool.',  #  noqa: E501
        ).with_channel("analysis"),
        Message.from_role_and_content(
            Role.ASSISTANT,
            '{"location": "Tokyo"}').with_channel("commentary").with_recipient(
                "functions.get_current_weather").with_content_type("json"),
    ])
    token_ids = harmony_encoding.render_conversation_for_completion(
        convo, Role.ASSISTANT)

    extracted_info = openai_tool_parser.extract_tool_calls(
        "",
        request=None,
        token_ids=token_ids,
    )
    assert extracted_info.tools_called
    expected_tool_calls = [
        ToolCall(function=FunctionCall(
            name="get_current_weather",
            arguments=json.dumps({"location": "Tokyo"}),
        ))
    ]
    assert_tool_calls(extracted_info.tool_calls, expected_tool_calls)
    assert extracted_info.content is None


def test_extract_tool_calls_multiple_tools(
    openai_tool_parser,
    harmony_encoding,
):
    convo = Conversation.from_messages([
        Message.from_role_and_content(
            Role.USER, "What is the weather in Tokyo based on where I'm at?"),
        Message.from_role_and_content(
            Role.ASSISTANT,
            'User asks: "What is the weather in Tokyo?" based on their location. We need to use get_current_weather tool and get_user_location tool.',  #  noqa: E501
        ).with_channel("analysis"),
        Message.from_role_and_content(
            Role.ASSISTANT,
            '{"location": "Tokyo"}').with_channel("commentary").with_recipient(
                "functions.get_current_weather").with_content_type("json"),
        Message.from_role_and_content(
            Role.ASSISTANT,
            '{"location": "Tokyo"}').with_channel("commentary").with_recipient(
                "functions.get_user_location").with_content_type("json"),
    ])
    token_ids = harmony_encoding.render_conversation_for_completion(
        convo,
        Role.ASSISTANT,
    )

    extracted_info = openai_tool_parser.extract_tool_calls(
        "",
        request=None,
        token_ids=token_ids,
    )
    assert extracted_info.tools_called
    expected_tool_calls = [
        ToolCall(function=FunctionCall(
            name="get_current_weather",
            arguments=json.dumps({"location": "Tokyo"}),
        )),
        ToolCall(function=FunctionCall(
            name="get_user_location",
            arguments=json.dumps({"location": "Tokyo"}),
        ))
    ]
    assert_tool_calls(extracted_info.tool_calls, expected_tool_calls)
    assert extracted_info.content is None