２つのファイルのDiffを取るときの備忘録

概要

• ２つのファイルのDiffを取って違った場合にFAILEDになるテストスクリプトを作りたい
• 比較する２つのファイル名が同じである
• 比較する２つのファイル名が同じ場合、WinMergeで同じことができるがPCがMacのためスクリプトを書くことにした

参考

環境

# Pythonのバージョンを確認
python --version
> Python 3.7.3

# pytestのインストール
> pip install pytest

# natsortのインストール
> pip install natsort

実装

test_compare.py

import os
import difflib
import glob
from natsort import natsorted
import pytest
import re


folder_1 = "/filepath/"
folder_2 = "/filepath/"

files_1 = natsorted(glob.glob(os.path.join(folder_1, "*.txt")))
files_2 = natsorted(glob.glob(os.path.join(folder_2, "*.txt")))



def get_testdata():

    testdata = []
    testdata_ids = []
    for filename_with_path in files_1:
        filename = os.path.basename(filename_with_path)
        filename = filename.split('.')[0]
        testdata.append(filename_with_path)
        testdata_ids.append(f'{filename}')
    
    return [testdata, testdata_ids]

testdata = get_testdata()[0]
testdata_ids = get_testdata()[1]


@pytest.mark.parametrize("id", testdata_ids)
#@pytest.mark.parametrize("id", range(len(files_1))) # [0, 1, 2, 3, 4]
def test_compare(id):
    
    target_file_1 = f"{folder_1}/{id}.txt"
    target_file_2 = f"{folder_2}/{id}.txt" 

    if not os.path.exists(target_file_1) or not os.path.exists(target_file_2):
        raise FileNotFoundError

    f_p = open(target_file_1).read()
    f_d = open(target_file_2).read()

    diff = difflib.unified_diff(f_p.split(), f_d.split())
    diff_str = '\n'.join(diff)
    # print(diff_str)

    assert not diff_str, f"{target_file_1}, {target_file_2} FAILED!!"

結果

============================================================================================= test session starts =============================================================================================
platform darwin -- Python 3.7.3, pytest-7.1.2, pluggy-0.13.1
rootdir: /Users/test
plugins: cov-2.12.1, freezegun-0.4.2, Faker-5.3.0, mock-3.7.0
collected 304 items                                                                                                                                                                                           

test_compare.py ....................................................................................................................................................................................... [ 60%]
.........................................................................................................................                                                                               [100%]

============================================================================================= 304 passed in 1.10s =============================================================================================