list-filetypes.py

#! python
import os, sys, mimetypes, pprint
from typing import Optional, Dict

# Lists the file types and their associated line endings in a file tree

types: Dict[str, list] = {}

def guess_filetype(path: str) -> Optional[str]:
    """Returns just the type returned by mimetypes.guess_type, not its encoding"""
    return mimetypes.guess_type(filepath)[0]

if len(sys.argv) <= 1:
    print('Please supply a root folder')
    exit()

root = os.path.abspath(sys.argv[1])

for folder, _, files in os.walk(root):
    for file in files:
        filepath = os.path.join(folder, file)
        filetype  = guess_filetype(filepath)
        if not filetype: continue
        __, extension = os.path.splitext(filepath)


        if filetype in types.keys():
            if extension in types[filetype]:
                continue
            else:
                types[filetype].append(extension)
        else:
            types[filetype] = [extension]

for k, v in types.items():
    print(k, v)