使用python filecmp模块的dircmp类可以很方便的比对两个目录，dircmp的用法已经有很多文章介绍，不再赘述。
可以help(filecmp.dircmp)查看帮助信息，其中提到的x.report()、x.report_partial_closure()，都只能打印两目录一级子目录的比较信息。而x.report_full_closure()可以递归打印所有子目录的比对信息，但是输出太多，大多数情况下我们可能只关心两目录的不同之处。
help(filecmp.dircmp) 摘选： | High level usage: | x = dircmp(dir1, dir2) | x.report() -> prints a report on the differences between dir1 and dir2 | or | x.report_partial_closure() -> prints report on differences between dir1 | and dir2, and reports on common immediate subdirectories. | x.report_full_closure() -> like report_partial_closure, | but fully recursive.
本文编写的脚本，重点关注并实现两个目标：
1)递归比对两个目录及其所有子目录。
2）仅输出两目录不同之处，包括文件名相同(common_files)但是文件不一致(diff_files)，以及左、右目录中独有的文件或子目录。
py脚本compare_dir.py内容如下：
# -*- coding: utf-8 -*-
"""
@desc 使用filecmp.dircmp递归比对两个目录，输出比对结果以及统计信息。
@author longfeiwlf
@date 2020-5-20
"""
from filecmp import dircmp
import sys
# 定义全局变量：
number_different_files = 0 # 文件名相同但不一致的文件数
number_left_only = 0 # 左边目录独有的文件或目录数
number_right_only = 0 # 右边目录独有的文件或目录数
def print_diff(dcmp):
"""递归比对两目录，如果有不同之处，打印出来，同时累加统计计数。"""
global number_different_files
global number_left_only
global number_right_only
for name in dcmp.diff_files:
print("diff_file found: %s/%s" % (dcmp.left, name))
number_different_files += 1
for name_left in dcmp.left_only:
print("left_only found: %s/%s" % (dcmp.left, name_left))
number_left_only += 1
for name_right in dcmp.right_only:
print("right_only found: %s/%s" % (dcmp.right, name_right))
number_right_only += 1
for sub_dcmp in dcmp.subdirs.values():
print_diff(sub_dcmp) # 递归比较子目录
if __name__ == '__main__':
try:
mydcmp = dircmp(sys.argv[1], sys.argv[2])
except IndexError as ie:
print(ie)
print("使用方法：python compare_dir_cn.py 目录1 目录2")
else:
print("\n比对结果详情: ")
print_diff(mydcmp)
if (number_different_files == 0 and number_left_only == 0
and number_right_only == 0):
print("\n两个目录完全一致!")
else:
print("\n比对结果统计:")
print("Total Number of different files is: "
+ str(number_different_files))
print("Total Number of files or directories only in '"
+ sys.argv[1] + "' is: " + str(number_left_only))
print("Total Number of files or directories only in '"
+ sys.argv[2] + "' is: " + str(number_right_only))
compare_dir.py脚本使用举例:
