[gpt-oss] tool parser supports for /chat/completions [1/n] (#22386)

Signed-off-by: Aaron Pham <contact@aarnphm.xyz>
Co-authored-by: Simon Mo <simon.mo@hey.com>

tests/tool_use/test_openai_tool_parser.py

@@ -0,0 +1,147 @@
+# 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