dirdiff.py

import os, sys
def reportdiffs(unique1, unique2, dir1, dir2):
    if not(unique1 or unique2):
        print('Directory lists are indetical')
    else:
        if unique1:
            print("Files unique to", dir1)
            for file in unique1:
                print('...', file)
        if unique2:
            print("Files unique to", dir2)
            for file in unique2:
                print('...', file)

def difference(seq1, seq2):
    return [item for item in seq1 if item not in seq2]

def comparedirs(dir1, dir2, files1=None, files2=None):
    print('Comparing', dir1, 'to', dir2)
    files1 = os.listdir(dir1) if files1 is None else files1
    files2 = os.listdir(dir2) if files2 is None else files2
    unique1 = difference(files1, files2)
    unique2 = difference(files2, files1)
    reportdiffs(unique1, unique2, dir1, dir2)
    return not(unique1 or unique2)

def getargs():
    try:
        dir1, dir2 = sys.argv[1:]
    except:
        print('Usage: dirdiff.py dir1 dir2')
        sys.exit(1)
    else:
        return(dir1, dir2)

if __name__ == '__main__':
    dir1, dir2 = getargs()
    comparedirs(dir1, dir2)