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@codeflash-ai codeflash-ai bot commented Jun 3, 2025

📄 125,980% (1,259.80x) speedup for sorter in code_to_optimize/bubble_sort.py

⏱️ Runtime : 4.93 seconds 3.91 milliseconds (best of 63 runs)

📝 Explanation and details

Here’s a faster rewrite of your function, using Python's built-in list.sort() method, which is implemented in C and highly optimized (Timsort algorithm). The functionality (in terms of output and in-place sorting) and print statements are preserved.


Why it's faster

  • The old approach is a pure-Python bubble sort O(N²); list.sort() is O(N log N) for most inputs and runs in optimized C code.
  • The result and printed output are unchanged, as required.

If, for some reason, you must not use built-in sort and need a manual fast implementation, a simple in-place quicksort or mergesort would still be much faster than bubble sort. But arr.sort() is fastest and most idiomatic in Python.

Correctness verification report:

Test Status
⚙️ Existing Unit Tests 13 Passed
🌀 Generated Regression Tests 54 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  # 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

# ------------------ 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
    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 = [3, 1, 2, 3, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

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

def test_sorter_list_with_single_element():
    # Single element list should be unchanged
    arr = [42]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

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

def test_sorter_list_with_identical_elements():
    # All elements identical
    arr = [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
    arr = []
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_integers():
    # List with very large integers
    arr = [sys.maxsize, -sys.maxsize-1, 0, 999999999, -999999999]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_floats():
    # List with floats
    arr = [1.5, 2.3, -0.1, 0.0, 2.3]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_mixed_int_float():
    # List with both ints and floats
    arr = [3, 1.1, 2, 3.5, 0]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

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

def test_sorter_single_character_strings():
    # List of single character strings
    arr = ["d", "a", "c", "b"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_unicode_strings():
    # List with unicode strings
    arr = ["á", "a", "ä", "b"]
    # Python's default sort is unicode code point order
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_case_sensitive_strings():
    # List with mixed case strings
    arr = ["apple", "Banana", "banana", "Apple"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

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

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

def test_sorter_list_with_nan():
    # List containing float('nan') should sort, but nan is always unordered
    arr = [3, float('nan'), 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# ------------------ LARGE SCALE TEST CASES ------------------

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

def test_sorter_large_identical_elements():
    # Large list with all identical elements
    arr = [42] * 1000
    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_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(-1e6, 1e6) for _ in range(1000)]
    expected = sorted(arr)
    codeflash_output = sorter(arr.copy()); result = codeflash_output

# ------------------ MUTATION TESTING CASES ------------------

def test_sorter_mutation_in_place():
    # Ensure the function sorts in place (since it mutates input)
    arr = [2, 1, 3]
    sorter(arr)

def test_sorter_return_value_is_input():
    # Ensure the returned list is the same object as input (in-place)
    arr = [3, 2, 1]
    codeflash_output = sorter(arr); 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 min/max integer edge cases

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

def test_sorter_unsorted_list():
    # Unsorted list with random order
    arr = [3, 1, 4, 5, 2]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_with_duplicates():
    # List with duplicate values
    arr = [4, 2, 2, 3, 1, 4]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_single_element():
    # List with a single element should remain unchanged
    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

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, -1]
    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_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_and_integers():
    # List with floats and integers
    arr = [3.5, 2, 4.1, 3.5, 1]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

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

def test_sorter_strings_with_case():
    # 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 characters
    arr = ["ápple", "apple", "äpple", "banana"]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_already_sorted_large_numbers():
    # Already sorted list with large numbers
    arr = [10**10, 10**11, 10**12]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_list_with_zeros():
    # List with zeros in various places
    arr = [0, 0, 1, 0, -1]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_list_with_boolean_values():
    # List with boolean values (should sort as 0 < 1)
    arr = [True, False, True, False]
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_mutation_side_effect():
    # Ensure that the input list is mutated (since sorter sorts in-place)
    arr = [2, 1]
    sorter(arr)


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

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

def test_sorter_large_random_list():
    # Large list of random integers (1000 elements)
    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 list already sorted (1000 elements)
    arr = list(range(1000))
    codeflash_output = sorter(arr.copy()); result = codeflash_output

def test_sorter_large_reverse_sorted_list():
    # Large list in reverse order (1000 elements)
    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
# 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-mbg6c8vc and push.

Codeflash

Here’s a **faster** rewrite of your function, using Python's built-in `list.sort()` method, which is implemented in C and highly optimized (Timsort algorithm). The functionality (in terms of output and in-place sorting) and print statements are preserved.



---

### Why it's faster

- The old approach is a pure-Python bubble sort O(N²); `list.sort()` is O(N log N) for most inputs and runs in optimized C code.
- The result and printed output are unchanged, as required.

---

If, for some reason, you **must not** use built-in sort and need a manual fast implementation, a simple in-place quicksort or mergesort would still be much faster than bubble sort. **But `arr.sort()` is fastest and most idiomatic in Python.**
@codeflash-ai codeflash-ai bot added the ⚡️ codeflash Optimization PR opened by Codeflash AI label Jun 3, 2025
@codeflash-ai codeflash-ai bot requested a review from misrasaurabh1 June 3, 2025 07:05
@codeflash-ai codeflash-ai bot deleted the codeflash/optimize-sorter-mbg6c8vc branch June 3, 2025 07:05
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⚡️ codeflash Optimization PR opened by Codeflash AI

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