Full pytest documentation¶

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開始使用

操作指南¶

How to invoke pytest
- 指定要執行哪個測試
- Getting help on version, option names, environment variables
- Profiling test execution duration
- Managing loading of plugins
- Other ways of calling pytest
How to write and report assertions in tests
- Asserting with the assert statement
- Assertions about approximate equality
- Assertions about expected exceptions
- Assertions about expected warnings
- Making use of context-sensitive comparisons
- Defining your own explanation for failed assertions
- Returning non-None value in test functions
- Assertion introspection details
How to use fixtures
- "Requesting" fixtures
- Autouse fixtures (fixtures you don't have to request)
- Scope: sharing fixtures across classes, modules, packages or session
- Teardown/Cleanup (AKA Fixture finalization)
- Safe teardowns
- Running multiple assert statements safely
- Fixtures can introspect the requesting test context
- Using markers to pass data to fixtures
- Factories as fixtures
- Parametrizing fixtures
- Using marks with parametrized fixtures
- Modularity: using fixtures from a fixture function
- Automatic grouping of tests by fixture instances
- Use fixtures in classes and modules with usefixtures
- Overriding fixtures on various levels
- Using fixtures from other projects
How to mark test functions with attributes
- Registering marks
- Raising errors on unknown marks
How to parametrize fixtures and test functions
- @pytest.mark.parametrize: parametrizing test functions
- Basic pytest_generate_tests example
- More examples
How to use temporary directories and files in tests
- The tmp_path fixture
- The tmp_path_factory fixture
- tmpdir 和 tmpdir_factory 夾具
- Temporary directory location and retention
How to monkeypatch/mock modules and environments
- Monkeypatching functions
- Monkeypatching returned objects: building mock classes
- Global patch example: preventing "requests" from remote operations
- 猴子修補環境變數
- 猴子修補字典
- API 參考
How to run doctests
- Encoding
- Using 'doctest' options
- Continue on failure
- Output format
- pytest-specific features
- Alternatives
How to re-run failed tests and maintain state between test runs
- Usage
- Rerunning only failures or failures first
- Behavior when no tests failed in the last run
- The new config.cache object
- Inspecting Cache content
- 清除快取內容
- Stepwise
How to manage logging
- caplog fixture
- Live Logs
- Customizing Colors
- Release notes
- Incompatible changes in pytest 3.4
How to capture stdout/stderr output
- Default stdout/stderr/stdin capturing behaviour
- Setting capturing methods or disabling capturing
- Using print statements for debugging
- Accessing captured output from a test function
How to capture warnings
- Controlling warnings
- @pytest.mark.filterwarnings
- Disabling warnings summary
- Disabling warning capture entirely
- DeprecationWarning and PendingDeprecationWarning
- Ensuring code triggers a deprecation warning
- Asserting warnings with the warns function
- Recording warnings
- Additional use cases of warnings in tests
- Custom failure messages
- Internal pytest warnings
- Resource Warnings
How to use skip and xfail to deal with tests that cannot succeed
- 略過測試函式
- XFail: mark test functions as expected to fail
- Skip/xfail with parametrize
How to install and use plugins
- Requiring/Loading plugins in a test module or conftest file
- Finding out which plugins are active
- Deactivating / unregistering a plugin by name
- Disabling plugins from autoloading
Writing plugins
- Plugin discovery order at tool startup
- conftest.py: local per-directory plugins
- Writing your own plugin
- Making your plugin installable by others
- Assertion Rewriting
- Requiring/Loading plugins in a test module or conftest file
- Accessing another plugin by name
- Registering custom markers
- Testing plugins
Writing hook functions
- hook function validation and execution
- firstresult: stop at first non-None result
- hook wrappers: executing around other hooks
- Hook function ordering / call example
- Declaring new hooks
- Using hooks in pytest_addoption
- Optionally using hooks from 3rd party plugins
- Storing data on items across hook functions
How to use pytest with an existing test suite
- Running an existing test suite with pytest
How to use unittest-based tests with pytest
- Benefits out of the box
- pytest features in unittest.TestCase subclasses
- Mixing pytest fixtures into unittest.TestCase subclasses using marks
- Using autouse fixtures and accessing other fixtures
How to implement xunit-style set-up
- Module level setup/teardown
- Class level setup/teardown
- Method and function level setup/teardown
How to set up bash completion

Further topics¶

Release announcements