Add a check for config file extension before loading

[j6k4m8]

Describe your changes

This PR adds a check (per #47) that ensures the config file path ends with .yaml.

Was thinking about adding a action=... class to the argument, but feels like overkill and this is much more readable. Feedback welcome if you prefer that technique!

Issue Link

Closes #47

Type of change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📖 Documentation (Addition or improvements to documentation)

Checklist before requesting a review

• My branch is up-to-date with the target branch - if not update your fork with the changes from the target branch (use pull with --rebase option if possible).
• I have performed a self-review of my code
• For any new/modified functions/classes I have added docstrings that clearly describe its purpose, expected inputs and returned values
• I have placed in-line comments to clarify the intent of any hard-to-understand passages of my code
• I have updated the documentation to cover introduced code changes
• I have added tests that prove my fix is effective or that my feature works
• I have given the PR a name that clearly describes the change, written in imperative form (context).
• I have requested a reviewer and an assignee (assignee is responsible for merging)

Checklist for reviewers

Each PR comes with its own improvements and flaws. The reviewer should check the following:

• the code is readable
• the code is well tested
• the code is documented (including return types and parameters)
• the code is easy to maintain

Author checklist after completed review

• I have added a line to the CHANGELOG describing this change, in a section
  reflecting type of change (add section where missing):
  • added: when you have added new functionality
  • changed: when default behaviour of the code has been changed
  • fixes: when your contribution fixes a bug

Checklist for assignee

• PR is up to date with the base branch
• the tests pass
• author has added an entry to the changelog (and designated the change as added, changed or fixed)
• Once the PR is ready to be merged, squash commits and merge the PR.

[leifdenby]

sorry for the delay @j6k4m8 - I was off ill for a while... 😞

All the tests pass now :) Do you want to update the changelog and we can get this merged in? Remember to add yourself to the list of contributors in pyproject.toml too

[leifdenby]

It's probably fair to call this a bug I think. I would be reasonable to assume that the application supports reading both .yaml and .yml when I state that we're using "yaml" files. But with your fix only supporting .yaml is now "expected behaviour" 😄

[j6k4m8]

I'd (very gently) agree that this is a bug, but I think reasonable to just enforce .yaml for now; it's an easy enough fix and I can't imagine a circumstance where someone can't rename a yml file... But of course, happy to add support for yml if you prefer!

PS: hope you're feeling better :)