pytest Quick Start Guide

封面

Title Page

Copyright and Credits

pytest Quick Start Guide

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Foreword

Contributors

About the author

About the reviewers

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Preface

Who this book is for

What this book covers

To get the most out of this book

Download the example code files

Conventions used

Get in touch

Reviews

Introducing pytest

Why spend time writing tests?

A quick look at the unittest module

Why pytest?

Summary

Writing and Running Tests

Installing pytest

pip and virtualenv

Writing and running tests

Running tests

Powerful asserts

Text differences

Lists

Dictionaries and sets

How does pytest do it?

Checking exceptions: pytest.raises

Checking exception messages

Checking warnings: pytest.warns

Comparing floating point numbers: pytest.approx

Organizing files and packages

Tests that accompany your code

Tests separate from your code

Useful command-line options

Keyword expressions: -k

Stop soon: -x --maxfail

Last failed failed first: --lf --ff

Output capturing: -s and --capture

Disabling capturing with -s

Capture methods with --capture

Traceback modes and locals: --tb --showlocals

--tb=long

--tb=short

--tb=native

--tb=line

--tb=no

--showlocals (-l)

Slow tests with --durations

Extra test summary: -ra

Configuration: pytest.ini

Additional command-line: addopts

Customizing a collection

Cache directory: cache_dir

Avoid recursing into directories: norecursedirs

Pick the right place by default: testpaths

Override options with -o/--override

Summary

Markers and Parametrization

Mark basics

Creating marks

Running tests based on marks

Applying marks to classes

Applying marks to modules

Custom marks and pytest.ini

Built-in marks

@pytest.mark.skipif

pytest.skip

pytest.importorskip

@pytest.mark.xfail

pytest.xfail

Parametrization

Enter @pytest.mark.parametrize

Applying marks to value sets

Customizing test IDs

Testing multiple implementations

Summary

Fixtures

Introducing fixtures

Enter fixtures

Setup/teardown

Composability

Sharing fixtures with conftest.py files

Scopes

Scopes in action

Autouse

@pytest.mark.usefixtures

Parametrizing fixtures

Using marks from fixtures

An overview of built-in fixtures

tmpdir

tmpdir_factory