自动化测试框架工具pytest教程1-快速入门

第1章 快速入门

什么是pytest？

pytest是强大的Python测试工具，它可以用于所有类型和级别的软件测试。 Pytest可以被开发团队，QA团队，独立测试小组，实践TDD的个人和开放源代码项目。实际上，整个互联网上的项目都是从unittest或者nose转向pytest，包括Mozilla和Dropbox。为什么？因为pytest提供
强大的功能，如’断言’重写，第三方插件模型，强大但简单的fixture模型。

pytest是软件测试框架，这意味着pytest是命令行工具。它会自动找到你写的测试，运行测试并报告结果。可编写插件或安装第三方来扩展插件。它可以用来测试Python发行版。它很容易与其他工具对接，如持续集成和网页自动化。

Pytest脱颖而出的原因：

• 简单
• 易读
• 用assert来测试失败，而不是self.assertEqual() 或者self.assertLessThan()
• 可运行unittest或nose测试。

事实上很多自动化测试平台，底层就是用驱动的。它们用flask或django等提供友好的页面展示，但是核心层还是在pytest和一些测试库的开发。

本文基于ubuntu 16，python3书写，但是在其他平台通常也应该可以执行。

• 代码地址

安装

# pip3 install pytestCollecting pytest  Downloading https://files.pythonhosted.org/packages/76/52/fc48d02492d9e6070cb672d9133382e83084f567f88eff1c27bd2c6c27a8/pytest-3.5.1-py2.py3-none-any.whl (192kB)    100% |████████████████████████████████| 194kB 992kB/s Requirement already satisfied: setuptools in /usr/lib/python3/dist-packages (from pytest) (20.7.0)Collecting pluggy<0.7,>=0.5 (from pytest)  Downloading https://files.pythonhosted.org/packages/ba/65/ded3bc40bbf8d887f262f150fbe1ae6637765b5c9534bd55690ed2c0b0f7/pluggy-0.6.0-py3-none-any.whlCollecting more-itertools>=4.0.0 (from pytest)  Downloading https://files.pythonhosted.org/packages/7a/46/886917c6a4ce49dd3fff250c01c5abac5390d57992751384fe61befc4877/more_itertools-4.1.0-py3-none-any.whl (47kB)    100% |████████████████████████████████| 51kB 2.3MB/s Collecting attrs>=17.4.0 (from pytest)  Downloading https://files.pythonhosted.org/packages/41/59/cedf87e91ed541be7957c501a92102f9cc6363c623a7666d69d51c78ac5b/attrs-18.1.0-py2.py3-none-any.whlRequirement already satisfied: six>=1.10.0 in /usr/lib/python3/dist-packages (from pytest) (1.10.0)Collecting py>=1.5.0 (from pytest)  Downloading https://files.pythonhosted.org/packages/67/a5/f77982214dd4c8fd104b066f249adea2c49e25e8703d284382eb5e9ab35a/py-1.5.3-py2.py3-none-any.whl (84kB)    100% |████████████████████████████████| 92kB 2.6MB/s tensorflow-tensorboard 1.5.1 has requirement bleach==1.5.0, but you'll have bleach 2.1.3 which is incompatible.tensorflow-tensorboard 1.5.1 has requirement html5lib==0.9999999, but you'll have html5lib 1.0.1 which is incompatible.Installing collected packages: pluggy, more-itertools, attrs, py, pytestSuccessfully installed attrs-18.1.0 more-itertools-4.1.0 pluggy-0.6.0 py-1.5.3 pytest-3.5.1$ pytest -h # 查看帮助usage: pytest [options] [file_or_dir] [file_or_dir] [...]positional arguments:  file_or_dirgeneral:  -k EXPRESSION         only run tests which match the given substring                        expression. An expression is a python evaluatable                        expression where all names are substring-matched                        against test names and their parent classes. Example:                        -k 'test_method or test_other' matches all test                        functions and classes whose name contains                        'test_method' or 'test_other', while -k 'not                        test_method' matches those that don't contain                        'test_method' in their names. Additionally keywords                        are matched to classes and functions containing extra                        names in their 'extra_keyword_matches' set, as well as                        functions which have names assigned directly to them.  -m MARKEXPR           only run tests matching given mark expression.                        example: -m 'mark1 and not mark2'.  --markers             show markers (builtin, plugin and per-project ones).  -x, --exitfirst       exit instantly on first error or failed test.  --maxfail=num         exit after first num failures or errors.  --strict              marks not registered in configuration file raise                        errors.  -c file               load configuration from `file` instead of trying to                        locate one of the implicit configuration files.  --continue-on-collection-errors                        Force test execution even if collection errors occur.  --rootdir=ROOTDIR     Define root directory for tests. Can be relative path:                        'root_dir', './root_dir', 'root_dir/another_dir/';                        absolute path: '/home/user/root_dir'; path with                        variables: '$HOME/root_dir'.  --fixtures, --funcargs                        show available fixtures, sorted by plugin appearance                        (fixtures with leading '_' are only shown with '-v')  --fixtures-per-test   show fixtures per test  --import-mode={prepend,append}                        prepend/append to sys.path when importing test                        modules, default is to prepend.  --pdb                 start the interactive Python debugger on errors.  --pdbcls=modulename:classname                        start a custom interactive Python debugger on errors.                        For example:                        --pdbcls=IPython.terminal.debugger:TerminalPdb  --capture=method      per-test capturing method: one of fd|sys|no.  -s                    shortcut for --capture=no.  --runxfail            run tests even if they are marked xfail  --lf, --last-failed   rerun only the tests that failed at the last run (or                        all if none failed)  --ff, --failed-first  run all tests but run the last failures first. This                        may re-order tests and thus lead to repeated fixture                        setup/teardown  --nf, --new-first     run tests from new files first, then the rest of the                        tests sorted by file mtime  --cache-show          show cache contents, don't perform collection or tests  --cache-clear         remove all cache contents at start of test run.  --lfnf={all,none}, --last-failed-no-failures={all,none}                        change the behavior when no test failed in the last                        run or no information about the last failures was                        found in the cachereporting:  -v, --verbose         increase verbosity.  -q, --quiet           decrease verbosity.  --verbosity=VERBOSE   set verbosity  -r chars              show extra test summary info as specified by chars                        (f)ailed, (E)error, (s)skipped, (x)failed, (X)passed,                        (p)passed, (P)passed with output, (a)all except pP.                        Warnings are displayed at all times except when                        --disable-warnings is set  --disable-warnings, --disable-pytest-warnings                        disable warnings summary  -l, --showlocals      show locals in tracebacks (disabled by default).  --tb=style            traceback print mode (auto/long/short/line/native/no).  --show-capture={no,stdout,stderr,log,all}                        Controls how captured stdout/stderr/log is shown on                        failed tests. Default is 'all'.  --full-trace          don't cut any tracebacks (default is to cut).  --color=color         color terminal output (yes/no/auto).  --durations=N         show N slowest setup/test durations (N=0 for all).  --pastebin=mode       send failed|all info to bpaste.net pastebin service.  --junit-xml=path      create junit-xml style report file at given path.  --junit-prefix=str    prepend prefix to classnames in junit-xml output  --result-log=path     DEPRECATED path for machine-readable result log.collection:  --collect-only        only collect tests, don't execute them.  --pyargs              try to interpret all arguments as python packages.  --ignore=path         ignore path during collection (multi-allowed).  --deselect=nodeid_prefix                        deselect item during collection (multi-allowed).  --confcutdir=dir      only load conftest.py's relative to specified dir.  --noconftest          Don't load any conftest.py files.  --keep-duplicates     Keep duplicate tests.  --collect-in-virtualenv                        Don't ignore tests in a local virtualenv directory  --doctest-modules     run doctests in all .py modules  --doctest-report={none,cdiff,ndiff,udiff,only_first_failure}                        choose another output format for diffs on doctest                        failure  --doctest-glob=pat    doctests file matching pattern, default: test*.txt  --doctest-ignore-import-errors                        ignore doctest ImportErrors  --doctest-continue-on-failure                        for a given doctest, continue to run after the first                        failuretest session debugging and configuration:  --basetemp=dir        base temporary directory for this test run.  --version             display pytest lib version and import information.  -h, --help            show help message and configuration info  -p name               early-load given plugin (multi-allowed). To avoid                        loading of plugins, use the `no:` prefix, e.g.                        `no:doctest`.  --trace-config        trace considerations of conftest.py files.  --debug               store internal tracing debug information in                        'pytestdebug.log'.  -o OVERRIDE_INI, --override-ini=OVERRIDE_INI                        override ini option with "option=value" style, e.g.                        `-o xfail_strict=True -o cache_dir=cache`.  --assert=MODE         Control assertion debugging tools. 'plain' performs no                        assertion debugging. 'rewrite' (the default) rewrites                        assert statements in test modules on import to provide                        assert expression information.  --setup-only          only setup fixtures, do not execute tests.  --setup-show          show setup of fixtures while executing tests.  --setup-plan          show what fixtures and tests would be executed but                        don't execute anything.pytest-warnings:  -W PYTHONWARNINGS, --pythonwarnings=PYTHONWARNINGS                        set which warnings to report, see -W option of python                        itself.logging:  --no-print-logs       disable printing caught logs on failed tests.  --log-level=LOG_LEVEL                        logging level used by the logging module  --log-format=LOG_FORMAT                        log format as used by the logging module.  --log-date-format=LOG_DATE_FORMAT                        log date format as used by the logging module.  --log-cli-level=LOG_CLI_LEVEL                        cli logging level.  --log-cli-format=LOG_CLI_FORMAT                        log format as used by the logging module.  --log-cli-date-format=LOG_CLI_DATE_FORMAT                        log date format as used by the logging module.  --log-file=LOG_FILE   path to a file when logging will be written to.  --log-file-level=LOG_FILE_LEVEL                        log file logging level.  --log-file-format=LOG_FILE_FORMAT                        log format as used by the logging module.  --log-file-date-format=LOG_FILE_DATE_FORMAT                        log date format as used by the logging module.[pytest] ini-options in the first pytest.ini|tox.ini|setup.cfg file found:  markers (linelist)       markers for test functions  empty_parameter_set_mark (string) default marker for empty parametersets  norecursedirs (args)     directory patterns to avoid for recursion  testpaths (args)         directories to search for tests when no files or directories are given in the command line.  console_output_style (string) console output: classic or with additional progress information (classic|progress).  usefixtures (args)       list of default fixtures to be used with this project  python_files (args)      glob-style file patterns for Python test module discovery  python_classes (args)    prefixes or glob names for Python test class discovery  python_functions (args)  prefixes or glob names for Python test function and method discovery  xfail_strict (bool)      default for the strict parameter of xfail markers when not given explicitly (default: False)  junit_suite_name (string) Test suite name for JUnit report  junit_logging (string)   Write captured log messages to JUnit report: one of no|system-out|system-err  doctest_optionflags (args) option flags for doctests  doctest_encoding (string) encoding used for doctest files  cache_dir (string)       cache directory path.  filterwarnings (linelist) Each line specifies a pattern for warnings.filterwarnings. Processed after -W and --pythonwarnings.  log_print (bool)         default value for --no-print-logs  log_level (string)       default value for --log-level  log_format (string)      default value for --log-format  log_date_format (string) default value for --log-date-format  log_cli (bool)           enable log display during test run (also known as "live logging").  log_cli_level (string)   default value for --log-cli-level  log_cli_format (string)  default value for --log-cli-format  log_cli_date_format (string) default value for --log-cli-date-format  log_file (string)        default value for --log-file  log_file_level (string)  default value for --log-file-level  log_file_format (string) default value for --log-file-format  log_file_date_format (string) default value for --log-file-date-format  addopts (args)           extra command line options  minversion (string)      minimally required pytest versionenvironment variables:  PYTEST_ADDOPTS           extra command line options  PYTEST_PLUGINS           comma-separated plugins to load during startup  PYTEST_DEBUG             set to enable debug tracing of pytest's internalsto see available markers type: pytest --markersto see available fixtures type: pytest --fixtures(shown according to specified file_or_dir or current dir if not specified; fixtures with leading '_' are only shown with the '-v' option

快速入门

def test_passing():    assert (1, 2, 3) == (1, 2, 3)

执行：

$ pytest pass_test.py =========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 1 item                                                                                          pass_test.py .                                                                                     [100%]======================================== 1 passed in 0.01 seconds =========================================

pass_test.py后的点表示一个测试运行并通过。 如果你需要更多信息，您可以使用-v或–verbose

$ pytest pass_test.py  -v=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0 -- /usr/bin/python3cachedir: .pytest_cacherootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 1 item                                                                                          pass_test.py ::test_passing PASSED                                                                        [100%]======================================== 1 passed in 0.01 seconds =========================================

在彩色终端，PASSED和底线是绿色的。

def test_failing():    assert (1, 2, 3) == (3, 2, 1)

执行：

$ pytest fail_test.py =========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 1 item                                                                                          fail_test.py F                                                                                       [100%]================================================ FAILURES =================================================______________________________________________ test_failing _______________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Use -v to get the full difffail_test.py :2: AssertionError======================================== 1 failed in 0.03 seconds =========================================$ pytest fail_test.py -v=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0 -- /usr/bin/python3cachedir: .pytest_cacherootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 1 item                                                                                          fail_test.py ::test_failing FAILED                                                                        [100%]================================================ FAILURES =================================================______________________________________________ test_failing _______________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Full diff:E         - (1, 2, 3)E         ?  ^     ^E         + (3, 2, 1)E         ?  ^     ^fail_test.py :2: AssertionError======================================== 1 failed in 0.02 seconds =========================================

如果没有参数，pytest会查看当前目录和所有子目录的测试文件(test_开头或者_test结尾)并运行。 也可以指定文件名，目录名称或这些名称的列表。

我们创建tasks的子目录，增加几个测试

task1_test.py

from collections import namedtupleTask = namedtuple('Task', ['summary', 'owner', 'done', 'id'])Task.__new__.__defaults__ = (None, None, False, None)def test_defaults():    """Using no parameters should invoke defaults."""    t1 = Task()    t2 = Task(None, None, False, None)    assert t1 == t2def test_member_access():    """Check .field functionality of namedtuple."""    t = Task('buy milk', 'brian')    assert t.summary == 'buy milk'    assert t.owner == 'brian'    assert (t.done, t.id) == (False, None)

task2_test.py

from collections import namedtupleTask = namedtuple('Task', ['summary', 'owner', 'done', 'id'])Task.__new__.__defaults__ = (None, None, False, None)def test_asdict():    """_asdict() should return a dictionary."""    t_task = Task('do something', 'okken', True, 21)    t_dict = t_task._asdict()    expected = {'summary': 'do something',                'owner': 'okken',                'done': True,                'id': 21}    assert t_dict == expecteddef test_replace():    """replace() should change passed in fields."""    t_before = Task('finish book', 'brian', False)    t_after = t_before._replace(id=10, done=True)    t_expected = Task('finish book', 'brian', True, 10)    assert t_after == t_expected

执行示例：

andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                         fail_test.py F                                                                                      [ 16%]pass_test.py .                                                                                      [ 33%]tasks/task1_test.py ..                                                                              [ 66%]tasks/task2_test.py ..                                                                              [100%]================================================ FAILURES =================================================______________________________________________ test_failing _______________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Use -v to get the full difffail_test.py:2: AssertionError=================================== 1 failed, 5 passed in 0.04 seconds ====================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest tasks=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                         tasks/task1_test.py ..                                                                              [ 50%]tasks/task2_test.py ..                                                                              [100%]======================================== 4 passed in 0.02 seconds =========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest -v tasks/task2_test.py::test_asdict=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0 -- /usr/bin/python3cachedir: .pytest_cacherootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 1 item                                                                                          tasks/task2_test.py::test_asdict PASSED                                                             [100%]======================================== 1 passed in 0.01 seconds =========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest --collect-only=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                         <Module 'fail_test.py'>  <Function 'test_failing'><Module 'pass_test.py'>  <Function 'test_passing'><Module 'tasks/task1_test.py'>  <Function 'test_defaults'>  <Function 'test_member_access'><Module 'tasks/task2_test.py'>  <Function 'test_asdict'>  <Function 'test_replace'>====================================== no tests ran in 0.02 seconds =======================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest --collect-only -k "asdict or defaults"=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items / 4 deselected                                                                          <Module 'tasks/task1_test.py'>  <Function 'test_defaults'><Module 'tasks/task2_test.py'>  <Function 'test_asdict'>====================================== 4 deselected in 0.02 seconds =======================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest -k "asdict or defaults"=========================================== test session starts ===========================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items / 4 deselected                                                                          tasks/task1_test.py .                                                                               [ 50%]tasks/task2_test.py .                                                                               [100%]================================= 2 passed, 4 deselected in 0.02 seconds ==================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ 

发现规则小结

• 测试文件应该命名为test_<something>.py或<something>_test.py
• 测试方法和函数应该被命名为test_<something>。
• 测试类应该被命名为Test<Something>

结果类型：

以下是测试功能的可能结果：

• PASSED (.)：测试成功。
• FAILED (F):测试失败(或XPASS + strict)。
• SKIPPED (s): 测试被跳过。 你可以使用@pytest.mark.skip()或 pytest.mark.skipif()修饰器告诉pytest跳过测试
• xfail (x)：预期测试失败。@pytest.mark.xfail()
• XPASS (X)：测试不应该通过。
• ERROR (E)：错误

更多选项

• marker 标签

比如只执行test_replace()和test_member_access()

import​ pytest...@pytest.mark.run_these_pleasedef​ test_member_access():...

test_replace()也进行同样的修改

$ ​ cd​​ ​ /path/to/code/ch1/tasks​ pytest​​ ​ -v​​ ​ -m​​ ​ run_these_please$================== test session starts ===================collected 4 itemstask2.py::test_replace PASSEDtask1.py::test_member_access PASSED=================== 2 tests deselected ============================ 2 passed, 2 deselected in 0.02 seconds =========

更多执行方法：-m “mark1 and mark2″、 -m “mark1 and not mark2″、-m “mark1 or mark2”

• -x, –exitfirst 失败后停止执行

  首次失败后停止执行：py.test -x

  py.test –maxfail=2 两次失败之后停止执行

$ pytest -x================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                                     fail_test.py F====================================================== FAILURES =======================================================____________________________________________________ test_failing _____________________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Use -v to get the full difffail_test.py:2: AssertionError============================================== 1 failed in 0.04 seconds ===============================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ 1$ pytest --tb=no================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                                     fail_test.py F                                                                                                  [ 16%]pass_test.py .                                                                                                  [ 33%]tasks/task1_test.py ..                                                                                          [ 66%]tasks/task2_test.py ..                                                                                          [100%]========================================= 1 failed, 5 passed in 0.05 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ $ pytest --maxfail=1 --tb=no================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                                     fail_test.py F============================================== 1 failed in 0.04 seconds ===============================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest --maxfail=2  --tb=no================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                                     fail_test.py F                                                                                                  [ 16%]pass_test.py .                                                                                                  [ 33%]tasks/task1_test.py ..                                                                                          [ 66%]tasks/task2_test.py ..                                                                                          [100%]========================================= 1 failed, 5 passed in 0.04 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ 

• 设置捕捉

默认捕捉方式为file descriptor (FD)级捕捉。捕捉所有到操作系统的1,2输出。

syslevel级捕捉只捕捉python的sys.stdout和sys.stderr。

py.test -s            # disable all capturing 实际为--capture=no这样print就可以在屏幕输出。py.test --capture=sys # replace sys.stdout/stderr with in-mem filespy.test --capture=fd  # also point filedescriptors 1 and 2 to temp file

• –lf, –last-failed 执行上次失败的测试

多在–tb 之后使用

–ff / –failed-first则会先执行失败的，然后执行成功的。

$ pytest --lf================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items / 5 deselected                                                                                      run-last-failure: rerun previous 1 failurefail_test.py F                                                                                                  [100%]====================================================== FAILURES =======================================================____________________________________________________ test_failing _____________________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Use -v to get the full difffail_test.py:2: AssertionError======================================= 1 failed, 5 deselected in 0.04 seconds ========================================$ pytest --ff --tb=no================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 6 items                                                                                                     run-last-failure: rerun previous 1 failure firstfail_test.py F                                                                                                  [ 16%]pass_test.py .                                                                                                  [ 33%]tasks/task1_test.py ..                                                                                          [ 66%]tasks/task2_test.py ..                                                                                          [100%]========================================= 1 failed, 5 passed in 0.04 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ 

• -q 静默模式

-q, –quiet decrease verbosity.

$ pytest -qF.....                                                                                                          [100%]====================================================== FAILURES =======================================================____________________________________________________ test_failing _____________________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Full diff:E         - (1, 2, 3)E         ?  ^     ^E         + (3, 2, 1)E         ?  ^     ^fail_test.py:2: AssertionError1 failed, 5 passed in 0.04 secondsandrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest -qqF.....                                                                                                          [100%]====================================================== FAILURES =======================================================____________________________________________________ test_failing _____________________________________________________    def test_failing():>       assert (1, 2, 3) == (3, 2, 1)E       assert (1, 2, 3) == (3, 2, 1)E         At index 0 diff: 1 != 3E         Full diff:E         - (1, 2, 3)E         ?  ^     ^E         + (3, 2, 1)E         ?  ^     ^fail_test.py:2: AssertionError

• -l 在traceback中显示本地变量

–showlocals 在traceback中显示本地变量

修改test_replace()中的t_expected = Task(​ ‘finish book’​ , ​ ‘brian’​ , True, 10)为t_expected = Task(​ ‘finish book’​ , ​ ‘brian’​ , True, 11)

py.test --showlocals 在traceback中显示本地变量py.test -l 在traceback中显示本地变量（快捷方式）

$ pytest tasks================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py .F                                                                                          [100%]====================================================== FAILURES =======================================================____________________________________________________ test_replace _____________________________________________________    def test_replace():        """replace() should change passed in fields."""        t_before = Task('finish book', 'brian', False)        t_after = t_before._replace(id=10, done=True)        t_expected = Task('finish book', 'brian', True, 11)>       assert t_after == t_expectedE       AssertionError: assert Task(summary=...e=True, id=10) == Task(summary='...e=True, id=11)E         At index 3 diff: 10 != 11E         Use -v to get the full difftasks/task2_test.py:26: AssertionError========================================= 1 failed, 3 passed in 0.04 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest tasks -l================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py .F                                                                                          [100%]====================================================== FAILURES =======================================================____________________________________________________ test_replace _____________________________________________________    def test_replace():        """replace() should change passed in fields."""        t_before = Task('finish book', 'brian', False)        t_after = t_before._replace(id=10, done=True)        t_expected = Task('finish book', 'brian', True, 11)>       assert t_after == t_expectedE       AssertionError: assert Task(summary=...e=True, id=10) == Task(summary='...e=True, id=11)E         At index 3 diff: 10 != 11E         Use -v to get the full difft_after    = Task(summary='finish book', owner='brian', done=True, id=10)t_before   = Task(summary='finish book', owner='brian', done=False, id=None)t_expected = Task(summary='finish book', owner='brian', done=True, id=11)tasks/task2_test.py:26: AssertionError========================================= 1 failed, 3 passed in 0.04 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ 

• –tb=style

py.test -l 在traceback中显示本地变量（快捷方式）py.test --tb=auto 默认格式，首尾为long，其他为shortpy.test --tb=long 详细的traceback信息格式化形式py.test --tb=native 标准库格式化形式, 没有额外信息py.test --tb=short 更短的traceback格式py.test --tb=line 每个错误一行py.test --tb=no 无tracebackpy.test --full-trace 最详细的格式

实例：

$ pytest tasks --tb no================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py .F                                                                                          [100%]========================================= 1 failed, 3 passed in 0.04 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest tasks --tb line================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py .F                                                                                          [100%]====================================================== FAILURES =======================================================/home/andrew/code/backup/pytest_testing/ch1/tasks/task2_test.py:26: AssertionError: assert Task(summary=...e=True, id=10) == Task(summary='...e=True, id=11)========================================= 1 failed, 3 passed in 0.03 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest tasks --tb short================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py .F                                                                                          [100%]====================================================== FAILURES =======================================================____________________________________________________ test_replace _____________________________________________________tasks/task2_test.py:26: in test_replace    assert t_after == t_expectedE   AssertionError: assert Task(summary=...e=True, id=10) == Task(summary='...e=True, id=11)E     At index 3 diff: 10 != 11E     Use -v to get the full diff========================================= 1 failed, 3 passed in 0.04 seconds ==========================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ vi tasks/task2_test.py andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest tasks  --duration=3================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py ..                                                                                          [100%]============================================== slowest 3 test durations ===============================================0.00s setup    tasks/task1_test.py::test_defaults0.00s setup    tasks/task2_test.py::test_asdict0.00s setup    tasks/task2_test.py::test_replace============================================== 4 passed in 0.02 seconds ===============================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$

• –durations=N

统计最慢执行时间

andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ pytest tasks  --duration=3================================================= test session starts =================================================platform linux -- Python 3.5.2, pytest-3.5.1, py-1.5.3, pluggy-0.6.0rootdir: /home/andrew/code/backup/pytest_testing/ch1, inifile:collected 4 items                                                                                                     tasks/task1_test.py ..                                                                                          [ 50%]tasks/task2_test.py ..                                                                                          [100%]============================================== slowest 3 test durations ===============================================0.00s setup    tasks/task1_test.py::test_defaults0.00s setup    tasks/task2_test.py::test_asdict0.00s setup    tasks/task2_test.py::test_replace============================================== 4 passed in 0.02 seconds ===============================================andrew@andrew-PowerEdge-T630:~/code/backup/pytest_testing/ch1$ 

参考资料

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