[Bugfix] Fix Deepseekv32 tool parser when stream interval > 1 (#36056)

tests/tool_parsers/test_deepseekv32_tool_parser.py

+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+"""Unit tests for DeepSeekV32ToolParser.
+
+These tests use a minimal mock tokenizer so no real model weights are required.
+"""
+
+import json
+from unittest.mock import MagicMock
+
+import pytest
+
+from vllm.tool_parsers.deepseekv32_tool_parser import DeepSeekV32ToolParser
+
+# ---------------------------------------------------------------------------
+# Helpers
+# ---------------------------------------------------------------------------
+
+# Token IDs are not used by the V32 parser logic, so we only need the
+# tokenizer object to be truthy (the parser checks `if not self.model_tokenizer`).
+MOCK_TOKENIZER = MagicMock()
+MOCK_TOKENIZER.get_vocab.return_value = {}
+
+
+def make_parser() -> DeepSeekV32ToolParser:
+    return DeepSeekV32ToolParser(MOCK_TOKENIZER)
+
+
+def make_tool_param(name: str, params: dict) -> MagicMock:
+    """Build a mock tool matching the ChatCompletionToolsParam shape."""
+    tool = MagicMock()
+    tool.function.name = name
+    tool.function.parameters = params
+    return tool
+
+
+def make_request(tools=None) -> MagicMock:
+    req = MagicMock()
+    req.tools = tools
+    return req
+
+
+# Shorthand for the DSML tokens used throughout
+FC_START = "<｜DSML｜function_calls>"
+FC_END = "</｜DSML｜function_calls>"
+INV_START = '<｜DSML｜invoke name="'
+INV_END = "</｜DSML｜invoke>"
+PARAM_START = '<｜DSML｜parameter name="'
+PARAM_END = "</｜DSML｜parameter>"
+
+
+def build_tool_call(func_name: str, params: dict[str, str]) -> str:
+    """Build a complete model-output tool call string."""
+    param_strs = "".join(
+        f'{PARAM_START}{k}" string="true">{v}{PARAM_END}' for k, v in params.items()
+    )
+    return f'{FC_START}\n{INV_START}{func_name}">\n{param_strs}\n{INV_END}\n{FC_END}'
+
+
+# ---------------------------------------------------------------------------
+# Tests: DeepSeekV32ToolParser._convert_param_value
+# ---------------------------------------------------------------------------
+
+
+class TestConvertParamValue:
+    @pytest.fixture
+    def parser(self):
+        return make_parser()
+
+    def test_null(self, parser):
+        assert parser._convert_param_value("null", "string") is None
+        assert parser._convert_param_value("NULL", "integer") is None
+
+    def test_string(self, parser):
+        assert parser._convert_param_value("hello", "string") == "hello"
+
+    def test_integer_valid(self, parser):
+        assert parser._convert_param_value("42", "integer") == 42
+
+    def test_integer_invalid_falls_back_to_str(self, parser):
+        assert parser._convert_param_value("abc", "int") == "abc"
+
+    def test_number_float(self, parser):
+        assert parser._convert_param_value("3.14", "number") == pytest.approx(3.14)
+
+    def test_number_whole_returns_int(self, parser):
+        assert parser._convert_param_value("5.0", "number") == 5
+        assert isinstance(parser._convert_param_value("5.0", "number"), int)
+
+    def test_boolean_true(self, parser):
+        assert parser._convert_param_value("true", "boolean") is True
+        assert parser._convert_param_value("1", "bool") is True
+
+    def test_boolean_false(self, parser):
+        assert parser._convert_param_value("false", "boolean") is False
+        assert parser._convert_param_value("False", "bool") is False
+
+    def test_object_valid_json(self, parser):
+        assert parser._convert_param_value('{"k": 1}', "object") == {"k": 1}
+
+    def test_object_invalid_json_falls_back(self, parser):
+        assert parser._convert_param_value("not-json", "object") == "not-json"
+
+    def test_array_valid_json(self, parser):
+        assert parser._convert_param_value("[1, 2]", "array") == [1, 2]
+
+    def test_unknown_type_tries_json_then_string(self, parser):
+        assert parser._convert_param_value("123", "unknown") == 123
+        assert parser._convert_param_value("hello", "unknown") == "hello"
+
+
+# ---------------------------------------------------------------------------
+# Tests: extract_tool_calls (non-streaming)
+# ---------------------------------------------------------------------------
+
+
+class TestExtractToolCalls:
+    @pytest.fixture
+    def parser(self):
+        return make_parser()
+
+    def test_no_tool_call(self, parser):
+        result = parser.extract_tool_calls("just some text", None)
+        assert not result.tools_called
+        assert result.tool_calls == []
+        assert result.content == "just some text"
+
+    def test_single_tool_no_params(self, parser):
+        model_output = f'{FC_START}\n{INV_START}get_time">\n{INV_END}\n{FC_END}'
+        result = parser.extract_tool_calls(model_output, None)
+        assert result.tools_called
+        assert len(result.tool_calls) == 1
+        assert result.tool_calls[0].function.name == "get_time"
+        assert json.loads(result.tool_calls[0].function.arguments) == {}
+
+    def test_single_tool_with_params(self, parser):
+        model_output = build_tool_call(
+            "get_weather", {"location": "SF", "date": "2024-01-16"}
+        )
+        result = parser.extract_tool_calls(model_output, None)
+        assert result.tools_called
+        assert len(result.tool_calls) == 1
+        tc = result.tool_calls[0]
+        assert tc.function.name == "get_weather"
+        assert json.loads(tc.function.arguments) == {
+            "location": "SF",
+            "date": "2024-01-16",
+        }
+
+    def test_content_before_tool_call(self, parser):
+        model_output = "Sure, let me check! " + build_tool_call(
+            "get_weather", {"location": "NYC"}
+        )
+        result = parser.extract_tool_calls(model_output, None)
+        assert result.tools_called
+        assert result.content == "Sure, let me check! "
+
+    def test_no_content_prefix_returns_none(self, parser):
+        model_output = build_tool_call("get_weather", {"location": "NYC"})
+        result = parser.extract_tool_calls(model_output, None)
+        assert result.tools_called
+        assert result.content is None
+
+    def test_multiple_tools(self, parser):
+        model_output = (
+            f"{FC_START}\n"
+            f'{INV_START}get_weather">\n'
+            f'{PARAM_START}location" string="true">SF{PARAM_END}\n'
+            f"{INV_END}\n"
+            f'{INV_START}get_weather">\n'
+            f'{PARAM_START}location" string="true">NYC{PARAM_END}\n'
+            f"{INV_END}\n"
+            f"{FC_END}"
+        )
+        result = parser.extract_tool_calls(model_output, None)
+        assert result.tools_called
+        assert len(result.tool_calls) == 2
+        assert json.loads(result.tool_calls[0].function.arguments) == {"location": "SF"}
+        assert json.loads(result.tool_calls[1].function.arguments) == {
+            "location": "NYC"
+        }
+
+
+# ---------------------------------------------------------------------------
+# Tests: extract_tool_calls_streaming
+# ---------------------------------------------------------------------------
+
+
+class TestExtractToolCallsStreaming:
+    """Simulate character-by-character streaming and verify reconstructed args."""
+
+    @pytest.fixture
+    def parser(self):
+        return make_parser()
+
+    def _stream(self, parser, full_text: str, request=None):
+        """Drive the parser line-by-line and collect non-None deltas.
+
+        Real tokenizers emit multi-character chunks, not individual characters.
+        Streaming character-by-character would never deliver the full sentinel
+        token (e.g. '｜DSML｜') in a single delta, so we split on newlines to
+        ensure each sentinel always lands in one chunk.
+        """
+        if request is None:
+            request = make_request()
+        # Split into lines, preserving the trailing newline in each chunk.
+        chunks: list[str] = []
+        remaining = full_text
+        while remaining:
+            nl = remaining.find("\n")
+            if nl == -1:
+                chunks.append(remaining)
+                break
+            chunks.append(remaining[: nl + 1])
+            remaining = remaining[nl + 1 :]
+
+        deltas = []
+        prev = ""
+        for chunk in chunks:
+            curr = prev + chunk
+            result = parser.extract_tool_calls_streaming(
+                previous_text=prev,
+                current_text=curr,
+                delta_text=chunk,
+                previous_token_ids=[],
+                current_token_ids=[],
+                delta_token_ids=[1],
+                request=request,
+            )
+            prev = curr
+            if result is not None:
+                deltas.append(result)
+        return deltas
+
+    def _reconstruct_args(self, deltas, tool_index=0) -> str:
+        """Concatenate all argument fragments for a given tool index."""
+        fragments = []
+        for d in deltas:
+            if d.tool_calls:
+                for tc in d.tool_calls:
+                    if tc.index == tool_index and tc.function and tc.function.arguments:
+                        fragments.append(tc.function.arguments)
+        return "".join(fragments)
+
+    def test_plain_content_no_tool(self, parser):
+        full_text = "Hello, world!"
+        deltas = self._stream(parser, full_text)
+        content = "".join(d.content for d in deltas if d.content is not None)
+        assert "Hello, world!" in content
+        assert all(not d.tool_calls for d in deltas)
+
+    def test_single_tool_streaming(self, parser):
+        full_text = build_tool_call("get_weather", {"location": "SF"})
+        deltas = self._stream(parser, full_text)
+        args_str = self._reconstruct_args(deltas)
+        assert json.loads(args_str) == {"location": "SF"}
+
+    def test_tool_name_emitted(self, parser):
+        full_text = build_tool_call("my_func", {"x": "1"})
+        deltas = self._stream(parser, full_text)
+        func_names = [
+            tc.function.name
+            for d in deltas
+            if d.tool_calls
+            for tc in d.tool_calls
+            if tc.function and tc.function.name
+        ]
+        assert any("my_func" in n for n in func_names)
+
+    def test_content_before_tool_call_streaming(self, parser):
+        full_text = "Thinking... " + build_tool_call("fn", {"a": "b"})
+        deltas = self._stream(parser, full_text)
+        content = "".join(d.content for d in deltas if d.content is not None)
+        assert "Thinking" in content
+
+    def test_type_conversion_in_streaming(self, parser):
+        tool = make_tool_param(
+            "add",
+            {
+                "type": "object",
+                "properties": {
+                    "x": {"type": "integer"},
+                    "y": {"type": "integer"},
+                },
+            },
+        )
+        request = make_request(tools=[tool])
+        full_text = build_tool_call("add", {"x": "3", "y": "4"})
+        deltas = self._stream(parser, full_text, request=request)
+        args_str = self._reconstruct_args(deltas)
+        assert json.loads(args_str) == {"x": 3, "y": 4}
+
+    def test_multiple_tools_streaming(self, parser):
+        full_text = (
+            f"{FC_START}\n"
+            f'{INV_START}func_a">\n'
+            f'{PARAM_START}p" string="true">v1{PARAM_END}\n'
+            f"{INV_END}\n"
+            f'{INV_START}func_b">\n'
+            f'{PARAM_START}q" string="true">v2{PARAM_END}\n'
+            f"{INV_END}\n"
+            f"{FC_END}"
+        )
+        deltas = self._stream(parser, full_text)
+
+        # Collect function names by index
+        names_by_index: dict[int, str] = {}
+        for d in deltas:
+            if d.tool_calls:
+                for tc in d.tool_calls:
+                    if tc.function and tc.function.name:
+                        names_by_index[tc.index] = tc.function.name
+
+        assert names_by_index.get(0) == "func_a"
+        assert names_by_index.get(1) == "func_b"
+
+        assert json.loads(self._reconstruct_args(deltas, tool_index=0)) == {"p": "v1"}
+        assert json.loads(self._reconstruct_args(deltas, tool_index=1)) == {"q": "v2"}
+
+    def test_state_reset_on_new_stream(self, parser):
+        """A second stream (previous_text == '') must reset state cleanly."""
+        full_text = build_tool_call("fn", {"k": "v"})
+        # First stream
+        self._stream(parser, full_text)
+        # Second stream - should produce identical results
+        deltas2 = self._stream(parser, full_text)
+        assert json.loads(self._reconstruct_args(deltas2)) == {"k": "v"}
+
+    def test_empty_arguments_streaming(self, parser):
+        """Invoke block with zero parameters should produce empty JSON."""
+        full_text = f'{FC_START}\n{INV_START}get_time">\n{INV_END}\n{FC_END}'
+        deltas = self._stream(parser, full_text)
+        args_str = self._reconstruct_args(deltas)
+        assert json.loads(args_str) == {}
+
+    def test_unique_tool_call_ids(self, parser):
+        """Each tool call in a parallel stream must get a distinct id."""
+        full_text = (
+            f"{FC_START}\n"
+            f'{INV_START}fn_a">\n'
+            f'{PARAM_START}x" string="true">1{PARAM_END}\n'
+            f"{INV_END}\n"
+            f'{INV_START}fn_b">\n'
+            f'{PARAM_START}y" string="true">2{PARAM_END}\n'
+            f"{INV_END}\n"
+            f"{FC_END}"
+        )
+        deltas = self._stream(parser, full_text)
+        ids = [
+            tc.id
+            for d in deltas
+            if d.tool_calls
+            for tc in d.tool_calls
+            if tc.id is not None
+        ]
+        assert len(ids) == 2
+        assert ids[0] != ids[1]
+
+    def test_eos_after_tool_calls(self, parser):
+        """EOS token (empty delta_text, non-empty delta_token_ids) returns
+        a non-None DeltaMessage so the serving framework can finalize."""
+        full_text = build_tool_call("fn", {"k": "v"})
+        # Drive through the full text first
+        deltas = self._stream(parser, full_text)
+        assert any(d.tool_calls for d in deltas)
+        # Now simulate EOS: empty delta_text, but token ids present
+        prev = full_text
+        result = parser.extract_tool_calls_streaming(
+            previous_text=prev,
+            current_text=prev,
+            delta_text="",
+            previous_token_ids=[],
+            current_token_ids=[],
+            delta_token_ids=[2],  # EOS token id
+            request=make_request(),
+        )
+        assert result is not None
+
+    def test_streaming_matches_non_streaming(self, parser):
+        """Streaming and non-streaming must produce the same result."""
+        full_text = build_tool_call(
+            "get_weather", {"location": "SF", "date": "2024-01-16"}
+        )
+        # Non-streaming
+        non_stream = parser.extract_tool_calls(full_text, None)
+        assert non_stream.tools_called
+        ns_name = non_stream.tool_calls[0].function.name
+        ns_args = json.loads(non_stream.tool_calls[0].function.arguments)
+        # Streaming
+        deltas = self._stream(parser, full_text)
+        s_names = [
+            tc.function.name
+            for d in deltas
+            if d.tool_calls
+            for tc in d.tool_calls
+            if tc.function and tc.function.name
+        ]
+        s_args = json.loads(self._reconstruct_args(deltas))
+        assert s_names[0] == ns_name
+        assert s_args == ns_args
+
+    def _stream_chunked(self, parser, full_text: str, chunk_size: int, request=None):
+        """Drive the parser with fixed-size chunks (simulates stream interval).
+
+        Unlike ``_stream`` which splits on newlines, this splits the text
+        into ``chunk_size``-character pieces so the start token can be
+        split across chunks — exactly what happens with stream interval > 1.
+        """
+        if request is None:
+            request = make_request()
+        chunks = [
+            full_text[i : i + chunk_size] for i in range(0, len(full_text), chunk_size)
+        ]
+        deltas = []
+        prev = ""
+        for chunk in chunks:
+            curr = prev + chunk
+            result = parser.extract_tool_calls_streaming(
+                previous_text=prev,
+                current_text=curr,
+                delta_text=chunk,
+                previous_token_ids=[],
+                current_token_ids=[],
+                delta_token_ids=[1],
+                request=request,
+            )
+            prev = curr
+            if result is not None:
+                deltas.append(result)
+        return deltas
+
+    def test_single_tool_chunked_stream_interval(self, parser):
+        """Start token split across chunks (stream interval > 1)."""
+        full_text = build_tool_call("get_weather", {"location": "SF"})
+        # Use a chunk size that splits the start token
+        deltas = self._stream_chunked(parser, full_text, chunk_size=5)
+        args_str = self._reconstruct_args(deltas)
+        assert json.loads(args_str) == {"location": "SF"}
+
+    def test_content_before_tool_chunked(self, parser):
+        """Content before tool call with chunked streaming."""
+        full_text = "Thinking... " + build_tool_call("fn", {"a": "b"})
+        deltas = self._stream_chunked(parser, full_text, chunk_size=7)
+        content = "".join(d.content for d in deltas if d.content is not None)
+        assert "Thinking" in content
+        args_str = self._reconstruct_args(deltas)
+        assert json.loads(args_str) == {"a": "b"}
+
+    def test_multiple_tools_chunked(self, parser):
+        """Multiple tools with chunked streaming."""
+        full_text = (
+            f"{FC_START}\n"
+            f'{INV_START}func_a">\n'
+            f'{PARAM_START}p" string="true">v1{PARAM_END}\n'
+            f"{INV_END}\n"
+            f'{INV_START}func_b">\n'
+            f'{PARAM_START}q" string="true">v2{PARAM_END}\n'
+            f"{INV_END}\n"
+            f"{FC_END}"
+        )
+        deltas = self._stream_chunked(parser, full_text, chunk_size=10)
+        assert json.loads(self._reconstruct_args(deltas, tool_index=0)) == {"p": "v1"}
+        assert json.loads(self._reconstruct_args(deltas, tool_index=1)) == {"q": "v2"}
+
+    def test_no_emission_while_incomplete(self, parser):
+        """No tool calls should be emitted until an invoke block completes."""
+        # Stream only a partial invoke (no closing tag)
+        partial_text = (
+            f"{FC_START}\n"
+            f'{INV_START}fn">\n'
+            f'{PARAM_START}k" string="true">val{PARAM_END}\n'
+        )
+        deltas = self._stream(parser, partial_text)
+        # Should have no tool call deltas yet
+        assert all(not d.tool_calls for d in deltas)