Clarify open-source license type

[mociepka]

Could you consider using an established open-source license for this project? Pytest uses the MIT license, which might be a suitable option. With the current license, I am unable to use this project in my work. I understand that the library code will not be used in production directly (as it is a development dependency), but the current licensing still limits users who are bound by company policies that mandate the use of open-source software only.

Thank you for your consideration.

[justinmayer]

As one of the maintainers of this project, I agree and hereby second this motion. 👍

While I am normally partial to (A)GPL licenses, in this case I do not have a strong opinion regarding which OSI-compliant license is selected.

[Teemu]

Isn't this a pretty established license? https://opensource.org/license/bsd-3-clause

I would have probably chosen MIT if given the choice, but we are pretty much stuck since there are too many contributors to relicense.

[justinmayer]

I had no idea the current LICENSE file in this project is based on one of the BSD licenses, albeit an older version that is not commonly seen in active use today. I suspect Michał did not realize that either.

That said, I think there are some changes I would suggest to improve the current situation:

1. Remove the "All rights reserved" line, which appeared in older versions of the BSD License but is not actually present in the 3-Clause BSD License.
2. Ensure that the license type (e.g., "3-Clause BSD License") is clearly visible somewhere on the main project page on GitHub. (This may happen automatically once item 1. above is resolved.)

As to why the "All rights reserved" line was removed from modern versions of the BSD license, and why I think it should be removed from this project's license, please read: https://opensource.stackexchange.com/questions/2121/mit-license-and-all-rights-reserved/4403#4403

@Teemu: Do you have any objections if I make the above change, bringing the project's LICENSE file in alignment with the 3-Clause BSD License?

Update: I took the liberty of submitting a pull request with this change, as seen in the PR link below.