Pytest

Pytest is a tool for writing and running tests.

See also

On writing pytest tests.

Install

Poetry

Listing 661 command line

poetry add --dev pytest

Version 1.2.1 and newer use:

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poetry add --group dev pytest

Pip

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python -m pip install pytest

Usage

Getting Help

Running Tests

Verbose Mode

• [ ] invocation (run)

  • [ ] help

  • [ ] running a single test (-k or test_name.py::test_name)

  • [ ] verbose mode

    • [ ] -v: verbose

    • [ ] -x: fail on first tests

    • [ ] -k: expression

    • [ ] -tb=short: shorter tracebacks

    • [ ] --pdb: start debugger on failures

    • [ ] --trace: start debugger with breakpoint at the beginning of each test

    • [ ] --pdbcls=IPython.terminal.debugger:TerminalPdb: use the ipython debugger

    • [ ] running single test, filtering to matching names

Quickref

Flag	Description
-h	Help
-x	Exit on first error
--pdb	start debugger on error
--trace	add breakpoint to beginning of each test
-s	don’t capture stdout and stderr
-l, --show-locals	show local variable and their values
--tb=short	print shorter tracebacks

See also

See also

• Pytest docs

• Testing Python Applications with Pytest

TODO

• [x] install

• [ ] setup

  • [ ] pyproject.html: testpaths, addopts

• [ ] conftest.py

• [ ] plugins

  • [ ] pytest-only (add only marker)

  • [ ] pytest-parametrization

  • [ ] pytest-clarity (prettier assert diffs)

  • [ ] adding to pyproject.toml

    [tool.pytest.ini_options]
    testpaths = ["tests"]
    addopts = "-vx"