PythonでDiff

　比較用の関数を作成

FileDiff.py

import difflib


def diff(file_name1, file_name2):
    f1 = open(file_name1, 'r')
    f2 = open(file_name2, 'r')
    d = difflib.Differ()
    diff = d.compare(f1.readlines(), f2.readlines())
    return '\n'.join(diff)

　サンプルコード

import os
import FileDiff

working_dir = r'C:\temp'
file1_name = 'diff_test01.txt'
file2_name = 'diff_test02.txt'

os.chdir(working_dir)

print(FileDiff.diff(file1_name, file2_name))

　テストファイル

diff_test01.txt

Mike is a good student!
Mike plays street fighters.
Mike plays soccer.

diff_test02.txt

Mike is a good student!
Addis plays king of fighters.
Mike plays socer.

　実行結果

  Mike is a good student!

- Mike plays street fighters.

+ Addis plays king of fighters.

- Mike plays soccer.
?               -

+ Mike plays socer.

ファイル以外のもの（各タイプを持っている内部関数など）を比較することも可能

import difflib
l = dir(list)
t = dir(tuple)
d = difflib.Differ()
diff = d.compare(l, t)
print('\n'.join(diff))

実行結果

  __add__
  __class__
  __contains__
  __delattr__
- __delitem__
  __dir__
  __doc__
  __eq__
  __format__
  __ge__
  __getattribute__
  __getitem__
+ __getnewargs__
  __gt__
  __hash__
- __iadd__
- __imul__
  __init__
  __init_subclass__
  __iter__
  __le__
  __len__
  __lt__
  __mul__
  __ne__
  __new__
  __reduce__
  __reduce_ex__
  __repr__
- __reversed__
  __rmul__
  __setattr__
- __setitem__
  __sizeof__
  __str__
  __subclasshook__
- append
- clear
- copy
  count
- extend
  index
- insert
- pop
- remove
- reverse
- sort