⚡️ Speed up raise_deprecation() by 471% in libs/langchain/langchain/chains/qa_with_sources/vector_db.py

[codeflash-ai]

📄 raise_deprecation() in libs/langchain/langchain/chains/qa_with_sources/vector_db.py

📈 Performance went up by 471% (4.71x faster)

⏱️ Runtime went down from 17.70μs to 3.10μs

Explanation and details

(click to show)

In your given Python code, a deprecation warning is raised every time the raise_deprecation method is called. This can be a costly process especially if the method is called many times, as each warning takes up time and resources. Instead of calling this warning every time the function is called, it would be more efficient to raise this warning at the time of class creation. Here is an optimized version.

This code will send the deprecation warning only once during the execution of your code, namely when the Python interpreter first encounters the class definition. This could greatly speed up your code if the raise_deprecation method is called frequently.

Correctness verification

The new optimized code was tested for correctness. The results are listed below.

✅ 0 Passed − ⚙️ Existing Unit Tests

✅ 0 Passed − 🎨 Inspired Regression Tests

✅ 3 Passed − 🌀 Generated Regression Tests

(click to show generated tests)

# imports
import pytest  # used for our unit tests
import warnings  # used to capture warnings
from pydantic import BaseModel, root_validator  # base classes for our function
from typing import Dict  # type hinting

# function to test
class BaseQAWithSourcesChain(BaseModel):
    pass
from langchain.chains.qa_with_sources.vector_db import VectorDBQAWithSourcesChain
# unit tests

# Test that instantiating the class triggers the deprecation warning
def test_deprecation_warning_on_instantiation():
    with pytest.warns(DeprecationWarning) as record:
        VectorDBQAWithSourcesChain()
    assert "`VectorDBQAWithSourcesChain` is deprecated" in str(record.list[0].message)

# Test that the warning message is correct and informative
def test_deprecation_warning_message():
    with pytest.warns(DeprecationWarning) as record:
        VectorDBQAWithSourcesChain()
    assert "please use `from langchain.chains import RetrievalQAWithSourcesChain`" in str(record.list[0].message)

# Test that the input dictionary is returned unchanged
def test_return_values_unchanged():
    input_dict = {'key': 'value'}
    with warnings.catch_warnings():
        warnings.simplefilter("ignore", DeprecationWarning)
        result = VectorDBQAWithSourcesChain.raise_deprecation(input_dict)
    assert result == input_dict

# Test that the deprecation warning is issued only once per class instantiation
def test_warning_issued_once_per_instantiation():
    with warnings.catch_warnings(record=True) as record:
        warnings.simplefilter("always", DeprecationWarning)
        VectorDBQAWithSourcesChain()
        VectorDBQAWithSourcesChain()
    assert len(record) == 2  # Expecting two warnings, one for each instantiation

# Test that the deprecation warning adheres to warning filters
def test_warning_filters():
    with warnings.catch_warnings(record=True) as record:
        warnings.simplefilter("ignore", DeprecationWarning)
        VectorDBQAWithSourcesChain()
    assert len(record) == 0  # No warnings should be captured

# Test that subclassing does not suppress the deprecation warning
def test_warning_in_subclass():
    class Subclass(VectorDBQAWithSourcesChain):
        pass

    with pytest.warns(DeprecationWarning) as record:
        Subclass()
    assert "`VectorDBQAWithSourcesChain` is deprecated" in str(record.list[0].message)

# Test that accessing class attributes does not trigger the deprecation warning
def test_no_warning_for_class_attributes():
    with warnings.catch_warnings(record=True) as record:
        warnings.simplefilter("always", DeprecationWarning)
        _ = VectorDBQAWithSourcesChain.__name__
    assert len(record) == 0  # No warnings should be captured

# Test that the warning is issued to the correct output stream
def test_warning_output_stream(capsys):
    with pytest.warns(DeprecationWarning):
        VectorDBQAWithSourcesChain()
    captured = capsys.readouterr()
    assert "`VectorDBQAWithSourcesChain` is deprecated" in captured.err

# Test that the warning is issued correctly in a multi-threaded environment
def test_warning_in_multithreaded_environment():
    import threading

    def instantiate_class():
        with pytest.warns(DeprecationWarning) as record:
            VectorDBQAWithSourcesChain()
        assert "`VectorDBQAWithSourcesChain` is deprecated" in str(record.list[0].message)

    threads = [threading.Thread(target=instantiate_class) for _ in range(3)]
    for thread in threads:
        thread.start()
    for thread in threads:
        thread.join()