Reintroduce warnings postponed in 6.0

[mcsitter]

• Include new tests or update existing tests when applicable.
• Allow maintainers to push and squash when merging my commits. Please uncheck this if you prefer to squash the commits yourself.
• Create changelog entries

I came across the comment # Uncomment this after 6.0 release (#7361). Here is my PR for this.
Still working on the changelog text. In deprecated.py there are explanations for the deprecations already. Should I just copy them and shorten where it makes sense?

closes #7361

[nicoddemus]

Thanks a lot @mcsitter for getting to this.

I've dug around the Git history to find the original deprecation messages for those entries, please see my comments. 👍

[The-Compiler]

I don't understand our deprecation plans here - all deprecations are errors now, even new deprecations we're introducing? In other words, there is no phase where new deprecations are warnings rather than errors?

[nicoddemus]

I don't understand our deprecation plans here - all deprecations are errors now, even new deprecations we're introducing? In other words, there is no phase where new deprecations are warnings rather than errors?

Yeah I didn't mention, but one of the first things we should do is #5585 and turn back PytestDeprecationWarning into normal warnings, instead of errors.

[nicoddemus]

After #7660 gets merged we can rebase this one. 👍

[nicoddemus]

Hi @mcsitter,

Could you please rebase your PR now that #7660 has been merged? Thanks!

[mcsitter]

Will do! I never rebased a branch in a PR. I think I have to 1. pull from upstream master with the rebase flag. Once I learned to 2. deal with merge conflicts, I will 3. push the changes to my fork.

I think a rebase can rewrite history, so i am trying to be careful.

[nicoddemus]

Will do! I never rebased a branch in a PR. I think I have to 1. pull from upstream master with the rebase flag. Once I learned to 2. deal with merge conflicts, I will 3. push the changes to my fork.

That's pretty much it, yes. Let us know if you run into trouble! Thanks!

I think a rebase can rewrite history, so i am trying to be careful.

You are right, a rebase normally rewrites history, but it is only on your fork so it is alright. 👍

[mcsitter]

Rebase done. Thank you for your support! Tests are also passing. This is really delightful 😄

[nicoddemus]

Looks great! Thanks a lot @mcsitter!