How to test that your add-on installs and uninstalls

This guide shows you how to write the canonical setup suite for a Plone add-on: the add-on installs, brings its pieces with it, and removes them again cleanly.

It assumes you have a package_name fixture—see How to set up pytest-plone in your add-on.

Check the product is installed

def test_product_installed(installer, package_name):
    assert installer.is_product_installed(package_name) is True

Check the browser layer is registered

def test_browserlayer(browser_layers):
    from my.addon.interfaces import IMyAddonLayer

    assert IMyAddonLayer in browser_layers

Check the profile version

def test_profile_version(profile_last_version, package_name):
    assert profile_last_version(f"{package_name}:default") == "1000"

Check the control panel is there

def test_controlpanel_installed(controlpanel_actions):
    assert "my-addon-controlpanel" in controlpanel_actions

Check the content type is registered

import pytest


@pytest.mark.parametrize(
    "behavior",
    [
        "plone.dublincore",
        "plone.namefromtitle",
        "plone.shortname",
    ],
)
def test_has_behavior(get_behaviors, behavior):
    assert behavior in get_behaviors("Person")

Check it uninstalls

The uninstalled fixture uninstalls the add-on for you. Pull it in with usefixtures so it runs before every test in the class:

import pytest


@pytest.mark.usefixtures("uninstalled")
class TestUninstall:
    def test_product_uninstalled(self, installer, package_name):
        assert installer.is_product_installed(package_name) is False

    def test_browserlayer_removed(self, browser_layers):
        from my.addon.interfaces import IMyAddonLayer

        assert IMyAddonLayer not in browser_layers

The uninstall check is the one developers most often skip, and it is the one that catches profiles that add things without removing them.