⚡️ Speed up method RemoteFileProvider.ls by 49%

[codeflash-ai]

📄 49% (0.49x) speedup for RemoteFileProvider.ls in panel/widgets/file_selector.py

⏱️ Runtime : 1.26 milliseconds → 845 microseconds (best of 186 runs)

📝 Explanation and details

The optimized code achieves a 48% speedup by eliminating redundant function calls and computations that were executed repeatedly within list comprehensions.

Key optimizations applied:

1. Cached urlparse() call: Instead of calling urlparse(path).scheme inside a lambda that gets evaluated for every item, the scheme is extracted once upfront and stored in a variable.

2. Eliminated lambda function overhead: Replaced lambda functions (dirs_fn and files_fn) with inline conditional logic, removing the function call overhead for each list comprehension iteration.

3. Optimized conditional logic: Introduced a colon_check flag to avoid redundant ":" not in x checks when there's no scheme prefix to apply.

4. Cached self.sep access: Stored self.sep in a local variable to avoid repeated attribute lookups.

Why this leads to speedup:

• Lambda elimination: The original code called lambda functions ~1000+ times in large datasets, each with function call overhead
• Reduced string operations: The colon check optimization avoids unnecessary string searching when no prefix needs to be applied
• Single urlparse call: Moving urlparse() outside the loops eliminates repeated URL parsing

Performance characteristics by test case:

• Small datasets (1-10 items): 2-12% improvement due to reduced overhead
• Large datasets (500-1000+ items): 74-119% improvement, as the optimization benefits compound with scale
• Scheme-based paths: Slightly smaller gains (~2-4%) since prefix logic is still needed, but still benefits from reduced function calls
• No-scheme paths: Larger gains (~7-15%) as the colon check optimization provides additional savings

The optimization is most effective for large directory listings where the eliminated per-item function call overhead provides substantial cumulative savings.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	🔘 None Found
🌀 Generated Regression Tests	✅ 75 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	🔘 None Found
📊 Tests Coverage	100.0%

🌀 Generated Regression Tests and Runtime

from unittest.mock import MagicMock
from urllib.parse import urlparse

# imports
import pytest
from panel.widgets.file_selector import RemoteFileProvider

# unit tests

# Helper: create a mock fs object with ls and glob methods
class MockFS:
    def __init__(self, ls_return, glob_return):
        self._ls_return = ls_return
        self._glob_return = glob_return

    def ls(self, path, detail=True):
        return self._ls_return

    def glob(self, pattern, detail=True):
        return self._glob_return

# Basic Test Cases

def test_ls_basic_single_file_and_dir():
    """Test with one directory and one file in root."""
    fs = MockFS(
        ls_return=[
            {'name': 'dir1', 'type': 'directory'},
            {'name': 'file1.txt', 'type': 'file'},
        ],
        glob_return={
            'file1.txt': {'name': 'file1.txt', 'type': 'file'}
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.49μs -> 9.32μs (1.76% faster)

def test_ls_basic_with_scheme():
    """Test with a scheme in the path (e.g., s3://)."""
    fs = MockFS(
        ls_return=[
            {'name': 'bucket/dir1', 'type': 'directory'},
            {'name': 'bucket/file1.txt', 'type': 'file'},
        ],
        glob_return={
            'bucket/file1.txt': {'name': 'bucket/file1.txt', 'type': 'file'}
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('s3://bucket') # 9.79μs -> 9.79μs (0.102% slower)

def test_ls_basic_multiple_files_and_dirs():
    """Test with multiple files and directories."""
    fs = MockFS(
        ls_return=[
            {'name': 'dirA', 'type': 'directory'},
            {'name': 'dirB', 'type': 'directory'},
            {'name': 'fileA.txt', 'type': 'file'},
            {'name': 'fileB.txt', 'type': 'file'},
        ],
        glob_return={
            'fileA.txt': {'name': 'fileA.txt', 'type': 'file'},
            'fileB.txt': {'name': 'fileB.txt', 'type': 'file'},
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.69μs -> 9.11μs (6.46% faster)

def test_ls_basic_file_pattern():
    """Test with a custom file pattern."""
    fs = MockFS(
        ls_return=[
            {'name': 'dirA', 'type': 'directory'},
            {'name': 'fileA.txt', 'type': 'file'},
            {'name': 'fileB.log', 'type': 'file'},
        ],
        glob_return={
            'fileB.log': {'name': 'fileB.log', 'type': 'file'},
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*.log') # 9.10μs -> 8.74μs (4.10% faster)

# Edge Test Cases

def test_ls_edge_empty_directory():
    """Test with an empty directory (no files or subdirs)."""
    fs = MockFS(ls_return=[], glob_return={})
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('emptydir') # 8.40μs -> 8.20μs (2.48% faster)

def test_ls_edge_no_trailing_slash():
    """Test path without trailing slash is handled correctly."""
    fs = MockFS(
        ls_return=[
            {'name': 'dir1', 'type': 'directory'},
            {'name': 'file1.txt', 'type': 'file'}
        ],
        glob_return={
            'file1.txt': {'name': 'file1.txt', 'type': 'file'}
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.43μs -> 8.57μs (10.1% faster)

def test_ls_edge_file_with_colon_in_name():
    """Test file and directory names containing ':' (should not add prefix)."""
    fs = MockFS(
        ls_return=[
            {'name': 'dir:withcolon', 'type': 'directory'},
        ],
        glob_return={
            'file:withcolon.txt': {'name': 'file:withcolon.txt', 'type': 'file'}
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.00μs -> 8.60μs (4.65% faster)

def test_ls_edge_scheme_in_path_and_colon_in_name():
    """Test with scheme and names containing ':'."""
    fs = MockFS(
        ls_return=[
            {'name': 'bucket/dir:withcolon', 'type': 'directory'},
        ],
        glob_return={
            'bucket/file:withcolon.txt': {'name': 'bucket/file:withcolon.txt', 'type': 'file'}
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('s3://bucket') # 9.60μs -> 9.25μs (3.83% faster)

def test_ls_edge_file_pattern_matches_none():
    """Test when file_pattern matches no files."""
    fs = MockFS(
        ls_return=[
            {'name': 'dir1', 'type': 'directory'},
            {'name': 'file1.txt', 'type': 'file'}
        ],
        glob_return={}
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*.log') # 8.89μs -> 8.50μs (4.62% faster)

def test_ls_edge_file_pattern_matches_all():
    """Test when file_pattern matches all files."""
    fs = MockFS(
        ls_return=[
            {'name': 'dir1', 'type': 'directory'},
            {'name': 'file1.txt', 'type': 'file'},
            {'name': 'file2.log', 'type': 'file'}
        ],
        glob_return={
            'file1.txt': {'name': 'file1.txt', 'type': 'file'},
            'file2.log': {'name': 'file2.log', 'type': 'file'},
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*') # 9.03μs -> 8.39μs (7.73% faster)

def test_ls_edge_dot_files_and_dirs():
    """Test that dotfiles are excluded by default pattern, included by '*'."""
    fs = MockFS(
        ls_return=[
            {'name': '.hidden_dir', 'type': 'directory'},
            {'name': 'visible_dir', 'type': 'directory'},
        ],
        glob_return={
            '.hidden_file': {'name': '.hidden_file', 'type': 'file'},
            'visible_file': {'name': 'visible_file', 'type': 'file'},
        }
    )
    provider = RemoteFileProvider(fs)
    # By default, only non-dot files
    dirs, files = provider.ls('root') # 9.58μs -> 8.72μs (9.87% faster)
    # With '*', dotfiles included
    dirs, files = provider.ls('root', '*') # 4.73μs -> 4.13μs (14.6% faster)

def test_ls_edge_path_is_file_not_dir():
    """Test when path is actually a file, not a directory."""
    fs = MockFS(
        ls_return=[
            {'name': 'file1.txt', 'type': 'file'},
        ],
        glob_return={
            'file1.txt': {'name': 'file1.txt', 'type': 'file'}
        }
    )
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('file1.txt') # 8.54μs -> 8.19μs (4.35% faster)

def test_ls_edge_nonexistent_path():
    """Test when path does not exist (simulate by raising error)."""
    class ErrorFS(MockFS):
        def ls(self, path, detail=True):
            raise FileNotFoundError("Path does not exist")
        def glob(self, pattern, detail=True):
            raise FileNotFoundError("Path does not exist")
    fs = ErrorFS([], {})
    provider = RemoteFileProvider(fs)
    with pytest.raises(FileNotFoundError):
        provider.ls('nonexistent') # 8.47μs -> 8.63μs (1.96% slower)

# Large Scale Test Cases

def test_ls_large_many_files_and_dirs():
    """Test with hundreds of files and directories."""
    num_dirs = 500
    num_files = 500
    ls_return = [{'name': f'dir{i}', 'type': 'directory'} for i in range(num_dirs)]
    ls_return += [{'name': f'file{i}.txt', 'type': 'file'} for i in range(num_files)]
    glob_return = {f'file{i}.txt': {'name': f'file{i}.txt', 'type': 'file'} for i in range(num_files)}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 119μs -> 65.4μs (82.0% faster)

def test_ls_large_all_files_match_pattern():
    """Test with all files matching a pattern."""
    num_files = 1000
    ls_return = []
    glob_return = {f'file{i}.log': {'name': f'file{i}.log', 'type': 'file'} for i in range(num_files)}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*.log') # 97.4μs -> 44.5μs (119% faster)

def test_ls_large_no_files_match_pattern():
    """Test with no files matching a pattern."""
    num_files = 1000
    ls_return = []
    glob_return = {}  # No files match
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*.nomatch') # 8.75μs -> 8.78μs (0.364% slower)

def test_ls_large_mixed_types_and_scheme():
    """Test with large number of dirs/files and a scheme."""
    num_dirs = 300
    num_files = 700
    ls_return = [{'name': f'bucket/dir{i}', 'type': 'directory'} for i in range(num_dirs)]
    ls_return += [{'name': f'bucket/file{i}.txt', 'type': 'file'} for i in range(num_files)]
    glob_return = {f'bucket/file{i}.txt': {'name': f'bucket/file{i}.txt', 'type': 'file'} for i in range(num_files)}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('s3://bucket') # 134μs -> 123μs (8.95% faster)

def test_ls_large_performance():
    """Test that function runs efficiently for large input."""
    import time
    num_dirs = 500
    num_files = 500
    ls_return = [{'name': f'dir{i}', 'type': 'directory'} for i in range(num_dirs)]
    ls_return += [{'name': f'file{i}.txt', 'type': 'file'} for i in range(num_files)]
    glob_return = {f'file{i}.txt': {'name': f'file{i}.txt', 'type': 'file'} for i in range(num_files)}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    start = time.time()
    dirs, files = provider.ls('root') # 118μs -> 66.5μs (77.9% faster)
    elapsed = time.time() - start
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
from unittest.mock import MagicMock
from urllib.parse import urlparse

# imports
import pytest
from panel.widgets.file_selector import RemoteFileProvider


# function to test
class BaseFileProvider:
    pass
from panel.widgets.file_selector import RemoteFileProvider


# Helper to create a mock filesystem
class MockFS:
    def __init__(self, ls_return, glob_return):
        self._ls_return = ls_return
        self._glob_return = glob_return

    def ls(self, path, detail=True):
        # Ignores path and detail for simplicity, returns the stored value
        return self._ls_return

    def glob(self, pattern, detail=True):
        # Ignores pattern and detail for simplicity, returns the stored value
        return self._glob_return

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

# 1. BASIC TEST CASES

def test_ls_basic_files_and_dirs():
    """Test listing a directory with both files and directories."""
    # Setup: 2 dirs, 2 files
    ls_return = [
        {'name': 'dir1', 'type': 'directory'},
        {'name': 'dir2', 'type': 'directory'},
        {'name': 'file1.txt', 'type': 'file'},
        {'name': 'file2.csv', 'type': 'file'},
    ]
    glob_return = {
        'file1.txt': {'name': 'file1.txt', 'type': 'file'},
        'file2.csv': {'name': 'file2.csv', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 10.5μs -> 9.87μs (6.41% faster)

def test_ls_basic_with_scheme():
    """Test listing with a path that has a scheme (e.g., s3://)."""
    ls_return = [
        {'name': 'bucket/dirA', 'type': 'directory'},
        {'name': 'bucket/fileA.txt', 'type': 'file'},
    ]
    glob_return = {
        'bucket/fileA.txt': {'name': 'bucket/fileA.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('s3://bucket') # 10.1μs -> 9.89μs (1.97% faster)

def test_ls_basic_empty_directory():
    """Test listing an empty directory."""
    ls_return = []
    glob_return = {}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('emptydir') # 8.57μs -> 8.20μs (4.59% faster)

def test_ls_basic_file_pattern():
    """Test listing with a custom file pattern."""
    ls_return = [
        {'name': 'dir1', 'type': 'directory'},
        {'name': 'file1.txt', 'type': 'file'},
        {'name': 'file2.log', 'type': 'file'},
    ]
    glob_return = {
        'file2.log': {'name': 'file2.log', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*.log') # 9.49μs -> 8.60μs (10.4% faster)

# 2. EDGE TEST CASES

def test_ls_edge_no_trailing_slash():
    """Test that path without trailing slash gets handled correctly."""
    ls_return = [
        {'name': 'dir1', 'type': 'directory'},
        {'name': 'file1.txt', 'type': 'file'},
    ]
    glob_return = {
        'file1.txt': {'name': 'file1.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.35μs -> 8.69μs (7.56% faster)

def test_ls_edge_directory_with_colon():
    """Test directory name containing a colon (should not get scheme prefix)."""
    ls_return = [
        {'name': 'dir:withcolon', 'type': 'directory'},
    ]
    glob_return = {}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 8.94μs -> 8.41μs (6.35% faster)

def test_ls_edge_file_with_colon():
    """Test file name containing a colon (should not get scheme prefix)."""
    ls_return = [
        {'name': 'file:withcolon.txt', 'type': 'file'},
    ]
    glob_return = {
        'file:withcolon.txt': {'name': 'file:withcolon.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 8.88μs -> 8.23μs (7.92% faster)

def test_ls_edge_only_directories():
    """Test when only directories are present."""
    ls_return = [
        {'name': 'dir1', 'type': 'directory'},
        {'name': 'dir2', 'type': 'directory'},
    ]
    glob_return = {}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.08μs -> 8.35μs (8.78% faster)

def test_ls_edge_only_files():
    """Test when only files are present."""
    ls_return = [
        {'name': 'file1.txt', 'type': 'file'},
        {'name': 'file2.txt', 'type': 'file'},
    ]
    glob_return = {
        'file1.txt': {'name': 'file1.txt', 'type': 'file'},
        'file2.txt': {'name': 'file2.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 9.06μs -> 8.18μs (10.7% faster)

def test_ls_edge_hidden_files():
    """Test that hidden files (starting with .) are not listed by default."""
    ls_return = [
        {'name': '.hidden', 'type': 'file'},
        {'name': 'visible.txt', 'type': 'file'},
    ]
    glob_return = {
        'visible.txt': {'name': 'visible.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 8.97μs -> 8.22μs (9.14% faster)

def test_ls_edge_nonstandard_file_types():
    """Test that only type 'file' and 'directory' are processed."""
    ls_return = [
        {'name': 'dir1', 'type': 'directory'},
        {'name': 'weird', 'type': 'symlink'},
    ]
    glob_return = {}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 8.60μs -> 8.21μs (4.69% faster)

def test_ls_edge_path_is_file():
    """Test that if path points to a file, result is empty dirs, file listed."""
    ls_return = [
        {'name': 'file1.txt', 'type': 'file'},
    ]
    glob_return = {
        'file1.txt': {'name': 'file1.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('file1.txt') # 8.91μs -> 8.28μs (7.60% faster)

def test_ls_edge_path_is_root():
    """Test that root path works as expected."""
    ls_return = [
        {'name': 'dir1', 'type': 'directory'},
        {'name': 'file1.txt', 'type': 'file'},
    ]
    glob_return = {
        'file1.txt': {'name': 'file1.txt', 'type': 'file'},
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('/') # 9.08μs -> 8.11μs (12.0% faster)

def test_ls_edge_scheme_and_colon_in_name():
    """Test that scheme is not added if name contains colon."""
    ls_return = [
        {'name': 's3:dir1', 'type': 'directory'},
    ]
    glob_return = {}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('s3://bucket') # 9.35μs -> 8.97μs (4.23% faster)

# 3. LARGE SCALE TEST CASES

def test_ls_large_many_files_and_dirs():
    """Test with a large number of files and directories."""
    # 500 dirs, 500 files
    ls_return = [
        {'name': f'dir{i}', 'type': 'directory'} for i in range(500)
    ] + [
        {'name': f'file{i}.txt', 'type': 'file'} for i in range(500)
    ]
    glob_return = {
        f'file{i}.txt': {'name': f'file{i}.txt', 'type': 'file'} for i in range(500)
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 118μs -> 67.6μs (76.1% faster)

def test_ls_large_only_files():
    """Test with a large number of files and no directories."""
    ls_return = [
        {'name': f'file{i}.txt', 'type': 'file'} for i in range(1000)
    ]
    glob_return = {
        f'file{i}.txt': {'name': f'file{i}.txt', 'type': 'file'} for i in range(1000)
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 134μs -> 65.6μs (105% faster)

def test_ls_large_only_directories():
    """Test with a large number of directories and no files."""
    ls_return = [
        {'name': f'dir{i}', 'type': 'directory'} for i in range(1000)
    ]
    glob_return = {}
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 114μs -> 63.2μs (81.6% faster)

def test_ls_large_mixed_file_types():
    """Test with a mix of file, directory, and other types."""
    ls_return = [
        {'name': f'dir{i}', 'type': 'directory'} for i in range(500)
    ] + [
        {'name': f'file{i}.txt', 'type': 'file'} for i in range(500)
    ] + [
        {'name': f'weird{i}', 'type': 'symlink'} for i in range(100)
    ]
    glob_return = {
        f'file{i}.txt': {'name': f'file{i}.txt', 'type': 'file'} for i in range(500)
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root') # 118μs -> 68.2μs (74.5% faster)

def test_ls_large_file_pattern():
    """Test with a large number of files and a restrictive file pattern."""
    ls_return = [
        {'name': f'file{i}.txt', 'type': 'file'} for i in range(1000)
    ]
    # Only files ending with '0.txt' are matched by the pattern
    glob_return = {
        f'file{i}.txt': {'name': f'file{i}.txt', 'type': 'file'} for i in range(0, 1000, 10)
    }
    fs = MockFS(ls_return, glob_return)
    provider = RemoteFileProvider(fs)
    dirs, files = provider.ls('root', '*0.txt') # 39.7μs -> 33.8μs (17.3% faster)
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
from panel.widgets.file_selector import RemoteFileProvider

To edit these changes git checkout codeflash/optimize-RemoteFileProvider.ls-mhbrn4zb and push.