⚡️ Speed up function detect_installation_method by 135%

[codeflash-ai]

📄 135% (1.35x) speedup for detect_installation_method in pdd/auto_update.py

⏱️ Runtime : 3.05 milliseconds → 1.30 milliseconds (best of 147 runs)

📝 Explanation and details

The optimization replaces any(marker in sys_executable for marker in ["/uv/tools/", ".local/share/uv/"]) with direct string checks: "/uv/tools/" in sys_executable or ".local/share/uv/" in sys_executable.

Key Performance Improvements:

• Eliminates generator overhead: The original code creates a generator expression and uses any() which has function call overhead and iteration mechanics
• Reduces list creation: Avoids creating the 2-element list ["/uv/tools/", ".local/share/uv/"] on each function call
• Direct string operations: Uses Python's optimized in operator for string searching directly, which is faster than iterating through a generator

Why it's faster:

• The any() function must set up iteration state and call next() repeatedly on the generator
• Generator expressions have creation overhead and maintain state between iterations
• Direct or evaluation with string in checks leverages Python's highly optimized string search algorithms without intermediate abstractions

Test case performance patterns:

• Consistent 135-200% speedup across all test scenarios, from simple paths to complex edge cases
• Best performance gains on UV paths (200-220% faster) since the first condition often matches early
• Strong performance even on large-scale tests (121-159% faster) with 1000+ iterations, showing the optimization scales well
• Effective on long paths (60-80% faster) where string searching is more expensive, demonstrating the reduced overhead pays off even in challenging cases

The optimization maintains identical functionality while removing Python runtime overhead layers.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	✅ 16 Passed
🌀 Generated Regression Tests	✅ 8168 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	🔘 None Found
📊 Tests Coverage	100.0%

⚙️ Existing Unit Tests and Runtime

Test File::Test Function	Original ⏱️	Optimized ⏱️	Speedup
test_auto_update.py::test_detect_pip_installation	3.13μs	1.55μs	102%✅
test_auto_update.py::test_detect_uv_installation	2.40μs	898ns	167%✅

🌀 Generated Regression Tests and Runtime

import pytest  # used for our unit tests
from pdd.auto_update import detect_installation_method

# unit tests

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

def test_basic_uv_tools_path():
    # Typical UV installation path
    codeflash_output = detect_installation_method("/home/user/.local/share/uv/tools/python3") # 1.27μs -> 402ns (215% faster)

def test_basic_uv_local_share_path():
    # Another common UV path
    codeflash_output = detect_installation_method("/home/user/.local/share/uv/python3") # 1.46μs -> 542ns (169% faster)

def test_basic_pip_usr_bin_path():
    # Typical pip installation path
    codeflash_output = detect_installation_method("/usr/bin/python3") # 1.18μs -> 441ns (167% faster)

def test_basic_pip_windows_path():
    # Windows pip path
    codeflash_output = detect_installation_method("C:\\Python39\\python.exe") # 1.22μs -> 437ns (179% faster)

def test_basic_pip_local_bin_path():
    # Local bin path for pip
    codeflash_output = detect_installation_method("/home/user/.local/bin/python3") # 1.23μs -> 460ns (167% faster)

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

def test_edge_empty_string():
    # Empty string should default to pip
    codeflash_output = detect_installation_method("") # 1.14μs -> 413ns (175% faster)

def test_edge_only_uv_tools_marker():
    # Path is exactly the marker
    codeflash_output = detect_installation_method("/uv/tools/") # 1.33μs -> 445ns (200% faster)

def test_edge_only_uv_local_share_marker():
    # Path is exactly the marker
    codeflash_output = detect_installation_method(".local/share/uv/") # 1.46μs -> 525ns (178% faster)

def test_edge_marker_at_end_of_path():
    # Marker at the end of the path
    codeflash_output = detect_installation_method("/usr/bin/.local/share/uv/") # 1.49μs -> 596ns (151% faster)

def test_edge_marker_at_start_of_path():
    # Marker at the start of the path
    codeflash_output = detect_installation_method("/uv/tools/python3") # 1.25μs -> 395ns (215% faster)

def test_edge_marker_in_middle_of_path():
    # Marker embedded in the middle of the path
    codeflash_output = detect_installation_method("/opt/xyz/.local/share/uv/python3") # 1.46μs -> 582ns (152% faster)

def test_edge_marker_with_additional_characters():
    # Marker with extra characters before/after
    codeflash_output = detect_installation_method("/uv/tools_extra/python3") # 1.18μs -> 447ns (164% faster)
    codeflash_output = detect_installation_method("/uv/toolss/python3") # 684ns -> 387ns (76.7% faster)
    codeflash_output = detect_installation_method("/uv/tools/python3_extra") # 609ns -> 248ns (146% faster)

def test_edge_case_sensitive_marker():
    # Case sensitivity: should not match if case is different
    codeflash_output = detect_installation_method("/UV/TOOLS/python3") # 1.16μs -> 436ns (166% faster)
    codeflash_output = detect_installation_method("/.LOCAL/SHARE/UV/python3") # 690ns -> 362ns (90.6% faster)

def test_edge_marker_with_spaces():
    # Marker with spaces should not match
    codeflash_output = detect_installation_method("/uv/ tools/python3") # 1.10μs -> 433ns (155% faster)
    codeflash_output = detect_installation_method("/.local/share/uv /python3") # 636ns -> 335ns (89.9% faster)

def test_edge_marker_with_trailing_slash():
    # Marker with trailing slash
    codeflash_output = detect_installation_method("/uv/tools//python3") # 1.27μs -> 394ns (222% faster)
    codeflash_output = detect_installation_method("/.local/share/uv//python3") # 776ns -> 366ns (112% faster)

def test_edge_path_with_multiple_markers():
    # Path containing both markers (should return 'uv')
    codeflash_output = detect_installation_method("/uv/tools/.local/share/uv/python3") # 1.16μs -> 379ns (207% faster)

def test_edge_path_with_marker_and_pip():
    # Path containing both marker and 'pip' substring
    codeflash_output = detect_installation_method("/uv/tools/pip/python3") # 1.09μs -> 376ns (190% faster)

def test_edge_marker_substring():
    # Marker substring (not full marker)
    codeflash_output = detect_installation_method("/uv/tool/python3") # 1.07μs -> 428ns (151% faster)
    codeflash_output = detect_installation_method("/.local/share/uvv/python3") # 674ns -> 369ns (82.7% faster)

def test_edge_marker_in_filename():
    # Marker in filename rather than directory
    codeflash_output = detect_installation_method("/home/user/uv_tools_python3") # 1.11μs -> 445ns (149% faster)

def test_edge_marker_with_unicode():
    # Unicode in path, marker present
    codeflash_output = detect_installation_method("/home/用户/.local/share/uv/python3") # 1.91μs -> 1.04μs (83.3% faster)
    # Unicode in path, marker absent
    codeflash_output = detect_installation_method("/home/用户/.local/share/uvv/python3") # 915ns -> 514ns (78.0% faster)

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

def test_large_scale_many_pip_paths():
    # Large number of pip paths, none should match UV
    paths = [f"/usr/bin/python{i}" for i in range(1000)]
    for path in paths:
        codeflash_output = detect_installation_method(path) # 358μs -> 161μs (122% faster)

def test_large_scale_many_uv_tools_paths():
    # Large number of UV tools paths, all should match UV
    paths = [f"/uv/tools/python{i}" for i in range(1000)]
    for path in paths:
        codeflash_output = detect_installation_method(path) # 355μs -> 137μs (159% faster)

def test_large_scale_mixed_paths():
    # Mix of UV and pip paths
    uv_paths = [f"/uv/tools/python{i}" for i in range(500)]
    pip_paths = [f"/usr/bin/python{i}" for i in range(500)]
    all_paths = uv_paths + pip_paths
    expected = ["uv"] * 500 + ["pip"] * 500
    for path, exp in zip(all_paths, expected):
        codeflash_output = detect_installation_method(path) # 358μs -> 149μs (140% faster)

def test_large_scale_edge_marker_at_various_positions():
    # Marker at different positions in the path
    for i in range(500):
        # Marker at start
        codeflash_output = detect_installation_method(f"/uv/tools/python{i}") # 188μs -> 78.4μs (141% faster)
        # Marker at end
        codeflash_output = detect_installation_method(f"/usr/bin/python{i}/uv/tools/")
        # Marker in middle
        codeflash_output = detect_installation_method(f"/usr/uv/tools/python{i}") # 181μs -> 71.3μs (155% faster)
        # Marker absent
        codeflash_output = detect_installation_method(f"/usr/bin/python{i}")

def test_large_scale_long_path_strings():
    # Very long path strings, marker present and absent
    base = "/usr/bin/" + "a" * 900
    codeflash_output = detect_installation_method(base) # 2.30μs -> 1.41μs (63.3% faster)
    uv_base = base + "/uv/tools/python3"
    codeflash_output = detect_installation_method(uv_base) # 842ns -> 398ns (112% faster)

def test_large_scale_randomized_paths():
    # Randomized paths, some with markers, some without
    import random
    random.seed(42)  # Deterministic
    markers = ["/uv/tools/", ".local/share/uv/"]
    for i in range(100):
        marker = random.choice(markers + [""])
        path = f"/home/user/{marker}python{i}"
        expected = "uv" if marker in markers else "pip"
        codeflash_output = detect_installation_method(path) # 42.4μs -> 18.4μs (130% faster)

# ------------------------
# Additional Robustness Tests
# ------------------------

def test_non_string_input_raises():
    # Function expects a string, so passing non-string should raise TypeError
    with pytest.raises(TypeError):
        detect_installation_method(None)
    with pytest.raises(TypeError):
        detect_installation_method(123)
    with pytest.raises(TypeError):
        detect_installation_method(['uv', 'tools'])

def test_path_with_newlines_and_tabs():
    # Path with newlines and tabs, marker present
    codeflash_output = detect_installation_method("/uv/tools/\npython3") # 1.74μs -> 648ns (168% faster)
    codeflash_output = detect_installation_method("/uv/tools/\tpython3") # 485ns -> 191ns (154% faster)
    # Path with newlines and tabs, marker absent
    codeflash_output = detect_installation_method("/usr/bin/\npython3") # 703ns -> 296ns (138% faster)
    codeflash_output = detect_installation_method("/usr/bin/\tpython3") # 415ns -> 165ns (152% faster)
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
import pytest  # used for our unit tests
from pdd.auto_update import detect_installation_method

# unit tests

# ------------------ BASIC TEST CASES ------------------

def test_basic_uv_tools_path():
    # Should detect UV if path contains '/uv/tools/'
    path = "/home/user/.local/share/uv/tools/python"
    codeflash_output = detect_installation_method(path) # 1.54μs -> 509ns (203% faster)

def test_basic_uv_local_share_path():
    # Should detect UV if path contains '.local/share/uv/'
    path = "/home/user/.local/share/uv/python"
    codeflash_output = detect_installation_method(path) # 1.56μs -> 628ns (149% faster)

def test_basic_pip_path_usr_bin():
    # Should detect pip if path is typical system python
    path = "/usr/bin/python3"
    codeflash_output = detect_installation_method(path) # 1.27μs -> 476ns (166% faster)

def test_basic_pip_path_env_python():
    # Should detect pip if path is from a virtualenv without UV markers
    path = "/home/user/.virtualenvs/myenv/bin/python"
    codeflash_output = detect_installation_method(path) # 1.29μs -> 525ns (145% faster)

def test_basic_pip_path_windows():
    # Should detect pip for Windows-style paths
    path = "C:\\Python39\\python.exe"
    codeflash_output = detect_installation_method(path) # 1.16μs -> 488ns (139% faster)

# ------------------ EDGE TEST CASES ------------------

def test_edge_empty_string():
    # Should default to pip if path is empty
    path = ""
    codeflash_output = detect_installation_method(path) # 1.10μs -> 378ns (192% faster)

def test_edge_only_uv_tools_marker():
    # Path is exactly the marker
    path = "/uv/tools/"
    codeflash_output = detect_installation_method(path) # 1.45μs -> 475ns (205% faster)

def test_edge_only_local_share_uv_marker():
    # Path is exactly the marker
    path = ".local/share/uv/"
    codeflash_output = detect_installation_method(path) # 1.43μs -> 541ns (165% faster)

def test_edge_uv_marker_in_middle():
    # Path contains the marker in the middle
    path = "/opt/other/uv/tools/custom/python"
    codeflash_output = detect_installation_method(path) # 1.33μs -> 457ns (190% faster)

def test_edge_uv_marker_at_end():
    # Path ends with marker
    path = "/some/path/.local/share/uv/"
    codeflash_output = detect_installation_method(path) # 1.45μs -> 557ns (160% faster)

def test_edge_case_sensitive():
    # Should not detect UV for different case
    path = "/UV/TOOLS/python"
    codeflash_output = detect_installation_method(path) # 1.15μs -> 468ns (146% faster)

def test_edge_marker_as_substring():
    # Marker is a substring but not a path segment
    path = "/home/user/luv/tools/python"
    codeflash_output = detect_installation_method(path) # 1.17μs -> 496ns (135% faster)

def test_edge_marker_overlap():
    # Marker overlaps but not exact
    path = "/uv/toolshed/python"
    codeflash_output = detect_installation_method(path) # 1.18μs -> 435ns (171% faster)

def test_edge_marker_in_filename():
    # Marker is part of filename, not path
    path = "/home/user/python-uv-tools"
    codeflash_output = detect_installation_method(path) # 1.17μs -> 467ns (151% faster)

def test_edge_multiple_uv_markers():
    # Path contains both markers
    path = "/home/user/.local/share/uv/uv/tools/python"
    codeflash_output = detect_installation_method(path) # 1.37μs -> 462ns (197% faster)

def test_edge_marker_with_trailing_slash():
    # Path contains marker with trailing slash
    path = "/home/user/.local/share/uv/"
    codeflash_output = detect_installation_method(path) # 1.45μs -> 563ns (158% faster)

def test_edge_marker_with_leading_space():
    # Path contains marker with leading space (should not match)
    path = " /uv/tools/python"
    codeflash_output = detect_installation_method(path) # 1.21μs -> 415ns (192% faster)

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

def test_large_scale_many_pip_paths():
    # Test with many pip paths, none should match UV
    for i in range(1000):
        path = f"/usr/bin/python{i}"
        codeflash_output = detect_installation_method(path) # 359μs -> 162μs (121% faster)

def test_large_scale_many_uv_paths():
    # Test with many UV paths, all should match UV
    for i in range(1000):
        path = f"/home/user/.local/share/uv/tools/python{i}"
        codeflash_output = detect_installation_method(path) # 359μs -> 140μs (156% faster)

def test_large_scale_mixed_paths():
    # Test with a mix of UV and pip paths
    for i in range(500):
        uv_path = f"/home/user/.local/share/uv/python{i}"
        pip_path = f"/usr/local/bin/python{i}"
        codeflash_output = detect_installation_method(uv_path) # 213μs -> 90.7μs (135% faster)
        codeflash_output = detect_installation_method(pip_path)

def test_large_scale_long_path():
    # Test with a very long path containing UV marker
    long_prefix = "/some/really/long/path/" * 50
    path = long_prefix + ".local/share/uv/python"
    codeflash_output = detect_installation_method(path) # 2.27μs -> 1.25μs (81.2% faster)

def test_large_scale_long_path_no_marker():
    # Test with a very long path without UV marker
    long_prefix = "/some/really/long/path/" * 50
    path = long_prefix + "python"
    codeflash_output = detect_installation_method(path) # 1.67μs -> 1.02μs (63.0% faster)

def test_large_scale_marker_at_various_positions():
    # Test marker at various positions in the path
    for i in range(10):
        prefix = "/foo/" * i
        suffix = "/bar/" * (10 - i)
        path = prefix + "/uv/tools/" + suffix + "python"
        codeflash_output = detect_installation_method(path) # 5.16μs -> 2.17μs (138% faster)

def test_large_scale_non_string_input():
    # Should raise TypeError if input is not a string
    with pytest.raises(TypeError):
        detect_installation_method(None)
    with pytest.raises(TypeError):
        detect_installation_method(123)
    with pytest.raises(TypeError):
        detect_installation_method(["/uv/tools/python"])
# 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-detect_installation_method-mgmp2e33 and push.