How to Filter Files by Extension and Size in Python

from pathlib import Path

def filter_files_by_extension(directory: str, extension: str) -> list:
    """Return a list of file names in directory with the given extension."""
    path = Path(directory)
    return [f.name for f in path.iterdir() if f.is_file() and f.suffix == extension]

def filter_files_by_size(directory: str, min_size: int = 0) -> list:
    """Return a list of (name, size) for files larger than min_size bytes."""
    path = Path(directory)
    return [(f.name, f.stat().st_size) for f in path.iterdir() if f.is_file() and f.stat().st_size > min_size]

if __name__ == "__main__":
    # Example: create a temp dir with sample files for demonstration
    import tempfile, os

    with tempfile.TemporaryDirectory() as tmpdir:
        for name in ["a.txt", "b.py", "c.md", "d.txt"]:
            Path(tmpdir, name).write_text("x" * 50)  # 50 bytes each

        # Create one larger file
        Path(tmpdir, "big.log").write_text("y" * 200)

        txt_files = filter_files_by_extension(tmpdir, ".txt")
        print("Text files:", txt_files)

        files_over_100_bytes = filter_files_by_size(tmpdir, min_size=100)
        print("Files > 100 bytes:", files_over_100_bytes)