avoid using actual user configurations during tests

[thorsten-klein]

Fixes #862

A new pytest fixture is added which is automatically applied (autouse=True).
This fixture sets the west environment variables WEST_CONFIG_SYSTEM and WEST_CONFIG_GLOBAL during each test, in order to prevent it from using or modifying the user's actual global or system configuration.

Note: The environment variables are inherited from subprocess, so that also the subprocess calls do not use or touch the user's real configs.

[thorsten-klein]

@pdgendt We could also create some invalid user config in the CI system (at the default path) to ensure that this corrupt config is never used in CI. Otherwise tests could potentially touch real configs again in future (e.g. when they use del os.environ['WEST_CONFIG_GLOBAL'])

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.34%. Comparing base (a3af732) to head (aa0b156).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #864      +/-   ##
==========================================
- Coverage   84.52%   84.34%   -0.18%     
==========================================
  Files          11       11              
  Lines        3366     3366              
==========================================
- Hits         2845     2839       -6     
- Misses        521      527       +6     

see 3 files with indirect coverage changes

[pdgendt]

Thanks for the fast fix! This looks good IMO.

[pdgendt]

@pdgendt We could also create some invalid user config in the CI system (at the default path) to ensure that this corrupt config is never used in CI. Otherwise tests could potentially touch real configs again in future (e.g. when they use del os.environ['WEST_CONFIG_GLOBAL'])

I like the idea, would even be better if we could verify that locally before CI, but not sure if that's easy.

[pdgendt]

Some styling fixes

[thorsten-klein]

I have added this new method update_env() which can be safely used in tests in order to unset env variables (instead of del os.environ). Maybe there is some way to forbid via conftest.oy that del os.environ is used?

[thorsten-klein]

I will rebase once your PR #865 is merged and run poe format 👍

[pdgendt]

I will rebase once your PR #865 is merged and run poe format 👍

Update this PR instead, so we can go ahead with this one. I'm afraid the formatting PR will need some more eyes and time.

[marc-hb]

I haven't looked at the code yet but it reminded me 6cf0a02... was this lost in the transition to uv?

[pdgendt]

I haven't looked at the code yet but it reminded me 6cf0a02... was this lost in the transition to uv?

I don't think so, it just wasn't noticed when new tests were added.

[pdgendt]

I haven't looked at the code yet but it reminded me 6cf0a02... was this lost in the transition to uv?

I don't think so, it just wasn't noticed when new tests were added.

Can confirm this issue exists in v1.5.0 running with tox.

[thorsten-klein]

We could also create some invalid user config in the CI system (at the default path) to ensure that this corrupt config is never used in CI

Let's tackle this in a follow-up PR 👍

Once a second reviewer has approved, this PR can be merged, correct?

[Copilot]

Pull Request Overview

This PR introduces test isolation for west configuration files to prevent tests from interfering with user's actual global and system configuration. The main change adds an autouse pytest fixture that sets environment variables to redirect config file locations during test execution.

Key changes:

• Added autouse fixture to isolate global and system config files during tests
• Refactored existing config test fixtures to use new context managers
• Introduced reusable update_env and chdir context managers

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
tests/conftest.py	Added autouse fixture for config isolation and utility context managers
tests/test_config.py	Updated to use new update_env context manager
tests/test_manifest.py	Refactored to use update_env instead of manual environment handling

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[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[pdgendt]

@mbolivar PTAL, as you're the original author of the environment mechanisms in tests.

I think the fix is elegant and more Pythonic.

[marc-hb]

I had a quick look and spotted nothing wrong, thanks for the fix.