chore: import upstream snapshot with attribution

tests/tool_use/test_chat_completion_request_validations.py

@@ -0,0 +1,183 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+import pytest
+
+from vllm.entrypoints.openai.chat_completion.protocol import ChatCompletionRequest
+
+
+def test_chat_completion_request_with_no_tools():
+    # tools key is not present
+    request = ChatCompletionRequest.model_validate(
+        {
+            "messages": [{"role": "user", "content": "Hello"}],
+            "model": "facebook/opt-125m",
+        }
+    )
+    assert request.tool_choice == "none"
+
+    # tools key is None
+    request = ChatCompletionRequest.model_validate(
+        {
+            "messages": [{"role": "user", "content": "Hello"}],
+            "model": "facebook/opt-125m",
+            "tools": None,
+        }
+    )
+    assert request.tool_choice == "none"
+
+    # tools key present but empty -- should be rejected
+    with pytest.raises(ValueError, match="must not be an empty array"):
+        ChatCompletionRequest.model_validate(
+            {
+                "messages": [{"role": "user", "content": "Hello"}],
+                "model": "facebook/opt-125m",
+                "tools": [],
+            }
+        )
+
+
+@pytest.mark.parametrize("tool_choice", ["auto", "required"])
+def test_chat_completion_request_with_tool_choice_but_no_tools(tool_choice):
+    with pytest.raises(
+        ValueError, match="When using `tool_choice`, `tools` must be set."
+    ):
+        ChatCompletionRequest.model_validate(
+            {
+                "messages": [{"role": "user", "content": "Hello"}],
+                "model": "facebook/opt-125m",
+                "tool_choice": tool_choice,
+            }
+        )
+
+    with pytest.raises(
+        ValueError, match="When using `tool_choice`, `tools` must be set."
+    ):
+        ChatCompletionRequest.model_validate(
+            {
+                "messages": [{"role": "user", "content": "Hello"}],
+                "model": "facebook/opt-125m",
+                "tool_choice": tool_choice,
+                "tools": None,
+            }
+        )
+
+
+def test_reasoning_content_normalized_to_reasoning():
+    request = ChatCompletionRequest.model_validate(
+        {
+            "messages": [
+                {"role": "user", "content": "What is 2+2?"},
+                {
+                    "role": "assistant",
+                    "content": "4",
+                    "reasoning_content": "2+2 equals 4",
+                },
+                {"role": "user", "content": "Are you sure?"},
+            ],
+            "model": "facebook/opt-125m",
+        }
+    )
+    assistant_msg = request.messages[1]
+    assert assistant_msg.get("reasoning") == "2+2 equals 4"
+    assert "reasoning_content" not in assistant_msg
+
+
+def test_reasoning_takes_precedence_over_reasoning_content():
+    request = ChatCompletionRequest.model_validate(
+        {
+            "messages": [
+                {"role": "user", "content": "What is 2+2?"},
+                {
+                    "role": "assistant",
+                    "content": "4",
+                    "reasoning": "from reasoning field",
+                    "reasoning_content": "from reasoning_content field",
+                },
+            ],
+            "model": "facebook/opt-125m",
+        }
+    )
+    assistant_msg = request.messages[1]
+    assert assistant_msg.get("reasoning") == "from reasoning field"
+    assert "reasoning_content" not in assistant_msg
+
+
+def test_no_reasoning_fields_unchanged():
+    request = ChatCompletionRequest.model_validate(
+        {
+            "messages": [
+                {"role": "user", "content": "Hello"},
+                {"role": "assistant", "content": "Hi"},
+            ],
+            "model": "facebook/opt-125m",
+        }
+    )
+    assistant_msg = request.messages[1]
+    assert assistant_msg.get("reasoning") is None
+    assert "reasoning_content" not in assistant_msg
+
+
+SAMPLE_TOOL = {
+    "type": "function",
+    "function": {
+        "name": "get_weather",
+        "description": "Get the weather",
+        "parameters": {
+            "type": "object",
+            "properties": {"location": {"type": "string"}},
+        },
+    },
+}
+
+
+def test_structured_outputs_with_named_tool_choice_rejected():
+    """structured_outputs cannot be combined with a named tool_choice."""
+    with pytest.raises(
+        ValueError,
+        match="structured outputs or tools, not both",
+    ):
+        ChatCompletionRequest.model_validate(
+            {
+                "messages": [{"role": "user", "content": "Hello"}],
+                "model": "facebook/opt-125m",
+                "tools": [SAMPLE_TOOL],
+                "tool_choice": {
+                    "type": "function",
+                    "function": {"name": "get_weather"},
+                },
+                "structured_outputs": {"json": {"type": "object"}},
+            }
+        )
+
+
+def test_structured_outputs_with_auto_tool_choice_allowed():
+    """structured_outputs with tool_choice 'auto' should be allowed."""
+    request = ChatCompletionRequest.model_validate(
+        {
+            "messages": [{"role": "user", "content": "Hello"}],
+            "model": "facebook/opt-125m",
+            "tools": [SAMPLE_TOOL],
+            "tool_choice": "auto",
+            "structured_outputs": {"json": {"type": "object"}},
+        }
+    )
+    assert request.tool_choice == "auto"
+
+
+def test_multiple_structured_outputs_rejected():
+    """Only one kind of structured output constraint is allowed."""
+    with pytest.raises(
+        ValueError,
+        match="You can only use one kind of constraints",
+    ):
+        ChatCompletionRequest.model_validate(
+            {
+                "messages": [{"role": "user", "content": "Hello"}],
+                "model": "facebook/opt-125m",
+                "structured_outputs": {
+                    "json": {"type": "object"},
+                    "regex": ".*",
+                },
+            }
+        )