⚡️ Speed up method DocumentUpdateIn.serialize_model by 25%

[codeflash-ai]

📄 25% (0.25x) speedup for DocumentUpdateIn.serialize_model in src/mistralai/models/documentupdatein.py

⏱️ Runtime : 40.1 microseconds → 31.9 microseconds (best of 78 runs)

📝 Explanation and details

The optimized code achieves a 25% speedup through several key performance improvements:

Primary optimizations:

1. Set-based membership checks: Converted optional_fields and nullable_fields from lists to sets ({"name"} vs ["name"]). This changes membership testing from O(n) to O(1), which is particularly beneficial when checking k in optional_fields and k in nullable_fields during each loop iteration.

2. Cached expensive attribute lookups: Moved self.__pydantic_fields_set__ and type(self).model_fields outside the loop to avoid repeated attribute access. These lookups involve Python's descriptor protocol and type introspection, which are costly when repeated.

3. Identity vs equality comparisons: Changed val != UNSET_SENTINEL to val is not UNSET_SENTINEL. Since UNSET_SENTINEL is a singleton, identity checks (is) are faster than equality checks (!=) as they bypass __eq__ method calls.

4. Conditional dictionary operations: Replaced unconditional serialized.pop(k, None) with conditional if k in serialized: serialized.pop(k). This avoids unnecessary hash lookups and pop operations when the key doesn't exist.

Performance impact by test case:

• Unset fields (55.6% faster): Benefits most from cached lookups and conditional pop operations
• Dict values (53.9% faster): Set-based membership checks show significant gains with complex values
• Basic operations (6-13% faster): Identity comparisons and cached lookups provide consistent improvements

These optimizations are particularly effective for serialization-heavy workloads where the same model fields are processed repeatedly.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	🔘 None Found
🌀 Generated Regression Tests	✅ 4013 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	🔘 None Found
📊 Tests Coverage	100.0%

🌀 Generated Regression Tests and Runtime

from __future__ import annotations

from typing import Any, Dict

# imports
import pytest
from mistralai.models.documentupdatein import DocumentUpdateIn
from pydantic import BaseModel, Field, model_serializer


# Sentinel values for testing
class UnsetSentinelType:
    pass

UNSET_SENTINEL = UnsetSentinelType()
UNSET = UNSET_SENTINEL

class OptionalNullable:
    """A wrapper to represent an optional nullable value."""
    def __init__(self, value):
        self.value = value
    def __eq__(self, other):
        # For testing, treat equality as value equality
        if isinstance(other, OptionalNullable):
            return self.value == other.value
        return self.value == other
from mistralai.models.documentupdatein import DocumentUpdateIn


# Helper function to simulate the handler
def default_handler(obj: BaseModel) -> Dict[str, Any]:
    # Simulate Pydantic's dict serialization
    result = {}
    for n, f in obj.model_fields.items():
        k = f.alias or n
        val = getattr(obj, n)
        # If the field is OptionalNullable, extract its value for serialization
        if isinstance(val, OptionalNullable):
            result[k] = val.value
        else:
            result[k] = val
    return result

# unit tests

# --- BASIC TEST CASES ---



def test_serialize_model_basic_unset():
    # Scenario: name is not set (remains UNSET)
    doc = DocumentUpdateIn()
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 6.90μs -> 4.88μs (41.3% faster)



















#------------------------------------------------
import pytest
from mistralai.models.documentupdatein import DocumentUpdateIn


# simulate UNSET and UNSET_SENTINEL as used in the function
class _UnsetType:
    pass

UNSET = _UnsetType()
UNSET_SENTINEL = _UnsetType()

# simulate OptionalNullable for type hints
def OptionalNullable(type_):
    return type_

# simulate BaseModel and minimal pydantic-like behaviors
class BaseModel:
    def __init__(self, **kwargs):
        self.__pydantic_fields_set__ = set(kwargs.keys())
        for key, value in kwargs.items():
            setattr(self, key, value)

# simulate model field objects with alias
class ModelField:
    def __init__(self, alias=None):
        self.alias = alias
from mistralai.models.documentupdatein import DocumentUpdateIn


# Helper handler function for serialization
def default_handler(obj):
    # returns dict of field names and their values
    result = {}
    for field in obj.model_fields:
        result[field] = getattr(obj, field, UNSET)
    return result

# -------------------- UNIT TESTS BEGIN --------------------

# 1. Basic Test Cases

def test_serialize_model_with_regular_string():
    """Test with a normal string value."""
    doc = DocumentUpdateIn(name="Test Document")
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 5.40μs -> 4.76μs (13.6% faster)

def test_serialize_model_with_none():
    """Test with None (nullable field)."""
    doc = DocumentUpdateIn(name=None)
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 4.20μs -> 3.94μs (6.41% faster)

def test_serialize_model_with_unset():
    """Test with UNSET (field not provided)."""
    doc = DocumentUpdateIn()
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 5.24μs -> 3.37μs (55.6% faster)

def test_serialize_model_with_empty_string():
    """Test with empty string."""
    doc = DocumentUpdateIn(name="")
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 3.69μs -> 3.48μs (6.03% faster)

# 2. Edge Test Cases





def test_serialize_model_with_field_set_to_dict():
    """Test with field set to a dict value."""
    doc = DocumentUpdateIn(name={"key": "value"})
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 6.90μs -> 4.48μs (53.9% faster)

def test_serialize_model_with_field_set_to_large_string():
    """Test with a very large string value."""
    large_str = "x" * 999
    doc = DocumentUpdateIn(name=large_str)
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 3.97μs -> 3.62μs (9.54% faster)

def test_serialize_model_with_field_set_to_special_characters():
    """Test with special unicode characters."""
    doc = DocumentUpdateIn(name="𝔘ñîçødë✨")
    codeflash_output = doc.serialize_model(default_handler); result = codeflash_output # 3.77μs -> 3.40μs (10.9% faster)

# 3. Large Scale Test Cases


def test_serialize_model_all_none():
    """Test serialization of many instances all set to None."""
    docs = [DocumentUpdateIn(name=None) for _ in range(999)]
    results = [doc.serialize_model(default_handler) for doc in docs]
    for result in results:
        pass

def test_serialize_model_all_unset():
    """Test serialization of many instances all unset."""
    docs = [DocumentUpdateIn() for _ in range(999)]
    results = [doc.serialize_model(default_handler) for doc in docs]
    for result in results:
        pass


def test_serialize_model_performance_large_scale():
    """Performance: serialize 999 instances with large strings."""
    large_str = "y" * 999
    docs = [DocumentUpdateIn(name=large_str) for _ in range(999)]
    results = [doc.serialize_model(default_handler) for doc in docs]
    for result in results:
        pass
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.

To edit these changes git checkout codeflash/optimize-DocumentUpdateIn.serialize_model-mh32p7ov and push.