Python單元測試框架之pytest---如何執行測試用例

時間 2019-11-30

標籤 python 單元測試框架 pytest 如何執行欄目 Python 简体版

原文原文鏈接

介紹 python

　　pytest是一個成熟的全功能的Python測試工具，能夠幫助你寫出更好的程序。session

適合從簡單的單元到複雜的功能測試python2.7

l 模塊化parametrizeable裝置（在2.3，持續改進）
l 參數化測試函數（用例）
l 標記測試功能與屬性
l Skip和xfail：處理不成功的測試用例（在2.4改進）
l 經過xdist插件分發測試到多個CPU
l 不斷地從新運行失敗的測試
l 靈活約定的Python測試發現

Home Page: http://pytest.org模塊化

安裝函數

>pip install -U pytest # 經過pip安裝工具

>py.test --version # 查看pytest版本測試

　This is pytest version 2.7.2, imported from C:\Python27\lib\site-packages\pytest.pycui

簡單的測試 this

　　讓咱們建立第一個文件，對個簡單的功能進行測試。spa

#coding=utf-8

# 功能
def func(x): return x + 1

# 測試用例
def test_answer(): assert func(3) == 5

切換到測試文件所在的目錄，經過「py.test」命令運行測試。

>py.test

執行結果以下圖：

===================================================================

在一個測試類中建立多個測試用例：

#coding=utf-8

class TestClass: def test_one(self): x = "this"
        assert "h" in x def test_two(self): x = "hello"
        assert x == "hi"

運行測試：

>py.test -q test_class.py

-q 爲quiet。表示在安靜的模式輸出報告訴。加不加這個參有什麼區別呢？讀者能夠對比一下兩次輸出的日誌。其實，就是少了一些pytest的版本信息。

===================================================================

從Python代碼中調用pytest

pytest中一樣提供了main() 來函數來執行測試用例。

pytest/

├── test_sample.py

├── test_class.py

└── test_main.py

此目錄爲咱們練習的目錄，打開test_mian.py

import pytest def test_main(): assert 5 != 5

if __name__ == '__main__': pytest.main()

直接運行該程序，sublime 中按Ctrl+B 運行。結果以下：

============================= test session starts ============================= platform win32 -- Python 2.7.10 -- py-1.4.30 -- pytest-2.7.2 rootdir: D:\pyse\pytest, inifile: collected 4 items test_class.py .F test_main.py F test_sample.py F ================================== FAILURES ===================================
_____________________________ TestClass.test_two ______________________________ self = <test_class.TestClass instance at 0x000000000304F548>

    def test_two(self): x = "hello"
>           assert x == "hi" E assert 'hello' == 'hi' E - hello E + hi test_class.py:11: AssertionError __________________________________ test_main __________________________________

    def test_main(): >       assert 5 != 5 E assert 5 != 5 test_main.py:4: AssertionError _________________________________ test_answer _________________________________

    def test_answer(): >       assert func(3) == 5 E assert 4 == 5 E +  where 4 = func(3) test_sample.py:9: AssertionError ===================== 3 failed, 1 passed in 0.03 seconds ====================== [Finished in 0.3s]

　　從執行結果看到，main() 默認執行了當前文件所在的目錄下的全部測試文件。

　　那麼，若是咱們只想運行某個測試文件呢？能夠向main()中添加參數，就像在cmd命令提示符下面同樣：

#coding=utf-8
import pytest def test_main(): assert 5 != 5

if __name__ == '__main__': pytest.main("-q test_main.py")   # 指定測試文件

運行結果：

F ================================== FAILURES ===================================
__________________________________ test_main __________________________________

    def test_main(): >       assert 5 != 5 E assert 5 != 5 test_main.py:4: AssertionError 1 failed in 0.01 seconds

那若是我想運行某個目錄下的測試用例呢？指定測試目錄便可。

#coding=utf-8
import pytest def test_main(): assert 5 != 5

if __name__ == '__main__': pytest.main("d:/pyse/pytest/")  # 指定測試目錄

建立運行測試腳本

　　有時候咱們的測試用例文件分散在不一樣的層級目錄下，經過命令行的方式運行測試顯示不太方便，如何編寫一個運行全部測試用例的腳本呢？ pytest能夠自動幫咱們生成這樣的腳本。

>py.test --genscript=runtests.py

打開生成的測runtests.py文件：

sources = """ eNrsve2S3EiSIDa3+jhtnvZ293Ra6SSdCZMUF0AzK1nk9OzM1nV2L4dNznKnm6TxY6dX1XVJVAJV halMIAkgWVU3O2d6Ar3CPYQeQn/1QjKTf8UnAplZ7O6ZPTNxpiszgQiPCA8PD3cPD/f/449+9/5H yds/W99M58v6fDqfl1XZzefv/9nbvxuPxxE8Oy+r8+jRy2dREq+bOt8siqaNo6zKo3hRV+1mRb/h a1UsuiKPPpRZdFncXNVN3qYRABmN3v/R23+OLbRd/v6/ePOf/tmPflSu1nXTRe1NOxotllnbRq+7 PKlPfwMw0qNR …… """

import sys import base64 import zlib class DictImporter(object): def __init__(self, sources): self.sources = sources def find_module(self, fullname, path=None): if fullname == "argparse" and sys.version_info >= (2,7): # we were generated with <python2.7 (which pulls in argparse)
            # but we are running now on a stdlib which has it, so use that.
            return None if fullname in self.sources: return self if fullname + '.__init__' in self.sources: return self return None def load_module(self, fullname): # print "load_module:", fullname
        from types import ModuleType try: s = self.sources[fullname] is_pkg = False except KeyError: s = self.sources[fullname + '.__init__'] is_pkg = True co = compile(s, fullname, 'exec') module = sys.modules.setdefault(fullname, ModuleType(fullname)) module.__file__ = "%s/%s" % (__file__, fullname) module.__loader__ = self if is_pkg: module.__path__ = [fullname] do_exec(co, module.__dict__) # noqa
        return sys.modules[fullname] def get_source(self, name): res = self.sources.get(name) if res is None: res = self.sources.get(name + '.__init__') return res if __name__ == "__main__": if sys.version_info >= (3, 0): exec("def do_exec(co, loc): exec(co, loc)\n") import pickle sources = sources.encode("ascii") # ensure bytes
        sources = pickle.loads(zlib.decompress(base64.decodebytes(sources))) else: import cPickle as pickle exec("def do_exec(co, loc): exec co in loc\n") sources = pickle.loads(zlib.decompress(base64.decodestring(sources))) importer = DictImporter(sources) sys.meta_path.insert(0, importer) entry = "import pytest; raise SystemExit(pytest.cmdline.main())" do_exec(entry, locals()) # noqa