⚡️ Speed up function sorter by 124,361%

[codeflash-ai]

📄 124,361% (1,243.61x) speedup for sorter in code_to_optimize/bubble_sort.py

⏱️ Runtime : 4.81 seconds → 3.87 milliseconds (best of 64 runs)

📝 Explanation and details

Here’s an optimized version using Python’s built-in sorting (which is highly efficient, Timsort, O(n log n)), while preserving all behaviors and comments. Also made sure to preserve the "Sorting list" output and result print.

This is dramatically faster than the original bubble sort while maintaining the function signature and output.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	✅ 13 Passed
🌀 Generated Regression Tests	✅ 65 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	🔘 None Found
📊 Tests Coverage	undefined

⚙️ Existing Unit Tests Details

- test_bubble_sort.py
- test_bubble_sort_conditional.py
- test_bubble_sort_import.py
- test_bubble_sort_in_class.py
- test_bubble_sort_parametrized.py
- test_bubble_sort_parametrized_loop.py

🌀 Generated Regression Tests Details

import random  # for generating large random lists
import string  # for string sorting tests
import sys  # for edge integer values

# imports
import pytest  # used for our unit tests
from code_to_optimize.bubble_sort import sorter

# unit tests

# -------------------------
# Basic Test Cases
# -------------------------

def test_sorter_sorted_list():
    # Already sorted list should remain unchanged
    arr = [1, 2, 3, 4, 5]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_reverse_sorted_list():
    # Reverse sorted list should be sorted ascending
    arr = [5, 4, 3, 2, 1]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_unsorted_list():
    # Random unsorted list
    arr = [3, 1, 4, 5, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_list_with_duplicates():
    # List with duplicate values
    arr = [4, 2, 5, 2, 3, 4]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_single_element():
    # List with a single element
    arr = [42]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_two_elements_sorted():
    # Two elements, already sorted
    arr = [1, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_two_elements_unsorted():
    # Two elements, unsorted
    arr = [2, 1]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_all_equal_elements():
    # All elements are the same
    arr = [7, 7, 7, 7, 7]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# -------------------------
# Edge Test Cases
# -------------------------

def test_sorter_empty_list():
    # Empty list should return empty list
    arr = []
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_negative_numbers():
    # List with negative numbers
    arr = [-3, -1, -4, -2, 0]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_mixed_positive_negative():
    # List with both positive and negative numbers
    arr = [3, -2, 0, -1, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_and_small_integers():
    # List with very large and very small integers
    arr = [sys.maxsize, -sys.maxsize-1, 0, 1, -1]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_floats():
    # List with float values
    arr = [3.1, 2.2, 5.5, 4.4, 1.0]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_mixed_int_float():
    # List with both int and float values
    arr = [3, 1.5, 2, 4.0, -1]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_strings():
    # List of strings (alphabetical order)
    arr = ["banana", "apple", "cherry", "date"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_strings_case_sensitive():
    # List of strings with different cases
    arr = ["Banana", "apple", "Cherry", "date"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_unicode_strings():
    # List with unicode strings
    arr = ["éclair", "apple", "Éclair", "banana"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_mutates_input():
    # Ensure the input list is mutated as bubble sort is in-place
    arr = [2, 1]
    sorter(arr)

def test_sorter_list_with_none_raises():
    # List with None should raise TypeError
    arr = [1, None, 2]
    with pytest.raises(TypeError):
        sorter(arr.copy())

def test_sorter_list_with_incomparable_types_raises():
    # List with incomparable types should raise TypeError
    arr = [1, "a", 2]
    with pytest.raises(TypeError):
        sorter(arr.copy())

def test_sorter_list_with_nan():
    # List with float('nan') should place nan at the end (Python's default)
    arr = [1, float('nan'), 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# -------------------------
# Large Scale Test Cases
# -------------------------

def test_sorter_large_random_list():
    # Large random list of integers
    arr = random.sample(range(-10000, -9000), 1000)
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_sorted_list():
    # Large already sorted list
    arr = list(range(1000))
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_reverse_sorted_list():
    # Large reverse sorted list
    arr = list(range(999, -1, -1))
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_duplicates():
    # Large list with many duplicates
    arr = [random.choice([1, 2, 3, 4, 5]) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_strings():
    # Large list of random strings
    arr = [''.join(random.choices(string.ascii_letters, k=5)) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_floats():
    # Large list of random floats
    arr = [random.uniform(-10000, 10000) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_negative_numbers():
    # Large list with only negative numbers
    arr = [random.randint(-10000, -1) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# -------------------------
# Mutation Testing Guards
# (Tests that catch subtle changes in behavior)
# -------------------------

def test_sorter_stability():
    # Ensure sorting is stable (relative order of equal elements is preserved)
    arr = [('a', 2), ('b', 1), ('c', 2), ('d', 1)]
    # Sort by the second item of the tuple
    arr_to_sort = arr.copy()
    # Custom key function, so we need to adapt sorter for this test by sorting by tuple[1]
    # But since the provided sorter does not support key, we skip this stability test
    # This test is here to remind that bubble sort is stable in principle

@pytest.mark.parametrize("arr,expected", [
    ([1, 2, 3, 4, 5], [1, 2, 3, 4, 5]),  # already sorted
    ([5, 4, 3, 2, 1], [1, 2, 3, 4, 5]),  # reverse sorted
    ([1, 2, 2, 1], [1, 1, 2, 2]),        # duplicates
    ([0], [0]),                          # single element
    ([], []),                            # empty list
])
def test_sorter_parametrize(arr, expected):
    # Parametrized test for basic scenarios
    codeflash_output = sorter(arr.copy()); result = codeflash_output
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.

import random  # used for generating large random lists
import string  # used for string sorting tests
import sys  # used for maxsize in edge cases

# imports
import pytest  # used for our unit tests
from code_to_optimize.bubble_sort import sorter

# unit tests

# -------------------------
# 1. Basic Test Cases
# -------------------------

def test_sorter_basic_sorted():
    # Already sorted list should remain unchanged
    arr = [1, 2, 3, 4, 5]
    expected = [1, 2, 3, 4, 5]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_reverse():
    # Reverse sorted list should be sorted ascending
    arr = [5, 4, 3, 2, 1]
    expected = [1, 2, 3, 4, 5]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_random():
    # Random order
    arr = [3, 1, 4, 5, 2]
    expected = [1, 2, 3, 4, 5]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_duplicates():
    # List with duplicates
    arr = [2, 3, 2, 1, 3]
    expected = [1, 2, 2, 3, 3]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_all_equal():
    # All elements are equal
    arr = [7, 7, 7, 7, 7]
    expected = [7, 7, 7, 7, 7]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_strings():
    # Sorting strings alphabetically
    arr = ["banana", "apple", "cherry"]
    expected = ["apple", "banana", "cherry"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_negative_numbers():
    # List with negative numbers
    arr = [-1, -3, 2, 0, -2]
    expected = [-3, -2, -1, 0, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_floats():
    # List with floats
    arr = [3.2, 1.5, 4.8, 2.1]
    expected = [1.5, 2.1, 3.2, 4.8]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_basic_mixed_int_float():
    # List with ints and floats
    arr = [3, 1.2, 4, 2.8]
    expected = [1.2, 2.8, 3, 4]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# -------------------------
# 2. Edge Test Cases
# -------------------------

def test_sorter_empty_list():
    # Empty list should return empty list
    arr = []
    expected = []
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_single_element():
    # Single element list should return same list
    arr = [42]
    expected = [42]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_two_elements_sorted():
    # Two elements, already sorted
    arr = [1, 2]
    expected = [1, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_two_elements_unsorted():
    # Two elements, unsorted
    arr = [2, 1]
    expected = [1, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_numbers():
    # List with very large and very small integers
    arr = [sys.maxsize, -sys.maxsize - 1, 0]
    expected = [-sys.maxsize - 1, 0, sys.maxsize]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_unicode_strings():
    # List with unicode strings
    arr = ["éclair", "apple", "Éclair", "banana"]
    expected = ["Éclair", "apple", "banana", "éclair"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_case_sensitive_strings():
    # List with mixed case strings
    arr = ["bob", "Alice", "alice", "Bob"]
    expected = ["Alice", "Bob", "alice", "bob"]  # Python's default sort is case-sensitive
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_mutation():
    # If the contract is that sorter should not mutate the input, test that
    arr = [3, 2, 1]
    arr_copy = arr.copy()
    sorter(arr)

def test_sorter_mutation_inplace():
    # If the contract is that sorter should mutate the input, test that
    arr = [3, 2, 1]
    sorter(arr)

def test_sorter_with_nan():
    # List containing float('nan') should keep nan at the end (since nan != nan)
    arr = [3.0, float('nan'), 2.0]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_with_infinity():
    # List containing float('inf') and float('-inf')
    arr = [1.0, float('inf'), -2.0, float('-inf')]
    expected = [float('-inf'), -2.0, 1.0, float('inf')]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_with_none():
    # List containing None should raise TypeError
    arr = [1, None, 2]
    with pytest.raises(TypeError):
        sorter(arr.copy())

def test_sorter_with_mixed_types():
    # List with mixed types (int and str) should raise TypeError
    arr = [1, "two", 3]
    with pytest.raises(TypeError):
        sorter(arr.copy())

# -------------------------
# 3. Large Scale Test Cases
# -------------------------

def test_sorter_large_random_list():
    # Sorting a large list of random integers
    arr = random.sample(range(1000), 1000)  # 1000 unique random ints
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_duplicates():
    # Sorting a large list with many duplicates
    arr = [random.choice([1, 2, 3, 4, 5]) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_sorted():
    # Sorting a large already sorted list
    arr = list(range(1000))
    expected = list(range(1000))
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_reverse_sorted():
    # Sorting a large reverse sorted list
    arr = list(range(999, -1, -1))
    expected = list(range(1000))
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_strings():
    # Sorting a large list of random strings
    arr = [''.join(random.choices(string.ascii_letters, k=5)) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# -------------------------
# Additional mutation-sensitive tests
# -------------------------

def test_sorter_stability():
    # Sorting should be stable: equal elements retain their relative order
    arr = [("a", 2), ("b", 1), ("c", 2), ("d", 1)]
    # Sort by second element
    arr_sorted = sorted(arr, key=lambda x: x[1])
    # Our sorter doesn't support key, so we test with a sortable list
    arr_simple = [2, 1, 2, 1]
    expected = [1, 1, 2, 2]
    codeflash_output = sorter(arr_simple.copy()); result = codeflash_output

def test_sorter_does_not_return_new_object():
    # If the contract is that sorter sorts in place and returns the same object
    arr = [4, 3, 2, 1]
    codeflash_output = sorter(arr); result = codeflash_output

def test_sorter_idempotence():
    # Sorting an already sorted list should not change it
    arr = [1, 2, 3, 4, 5]
    codeflash_output = sorter(arr.copy()); sorted_once = codeflash_output
    codeflash_output = sorter(sorted_once.copy()); sorted_twice = codeflash_output
# 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-sorter-mbg3nrbu and push.