pytest-env

This is a pytest plugin that enables you to set environment variables in a pytest.ini or pyproject.toml file.

Installation

Install with pip:

pip install pytest-env

Usage

Native form in `pyproject.toml`

[tool.pytest_env]
HOME = "~/tmp"
RUN_ENV = 1
TRANSFORMED = {value = "{USER}/alpha", transform = true}
SKIP_IF_SET = {value = "on", skip_if_set = true}

The tool.pytest_env tables keys are the environment variables keys to set. The right hand side of the assignment:

if an inline table you can set options via the transform or skip_if_set keys, while the value key holds the value to set (or transform before setting). For transformation the variables you can use is other environment variable,
otherwise the value to set for the environment variable to set (casted to a string).

Via pytest configurations

In your pytest.ini file add a key value pair with env as the key and the environment variables as a line separated list of KEY=VALUE entries. The defined variables will be added to the environment before any tests are run:

[pytest]
env =
    HOME=~/tmp
    RUN_ENV=test

Or with pyproject.toml:

[tool.pytest.ini_options]
env = [
    "HOME=~/tmp",
    "RUN_ENV=test",
]

Only set if not already set

You can use D: (default) as prefix if you don't want to override existing environment variables:

[pytest]
env =
    D:HOME=~/tmp
    D:RUN_ENV=test

Transformation

You can use existing environment variables using a python-like format, these environment variables will be expended before setting the environment variable:

[pytest]
env =
    RUN_PATH=/run/path/{USER}

You can apply the R: prefix to keep the raw value and skip this transformation step (can combine with the D: flag, order is not important):

[pytest]
env =
    R:RUN_PATH=/run/path/{USER}
    R:D:RUN_PATH_IF_NOT_SET=/run/path/{USER}

pytest-dev/pytest-env