New-DbaDbUser: Refactoring and bugfixing

[andreasjordan]

Type of Change

• Bug fix (non-breaking change, fixes New-DbaDbUser - Multiple -SqlInstance Without -Database Doesn't Add User To All Dbs #9340 )
• New feature (non-breaking change, adds functionality, fixes # )
• Breaking change (affects multiple commands or functionality, fixes # )
• Ran manual Pester test and has passed (.\tests\manual.pester.ps1)
• Adding code coverage to existing functionality
• Pester test is included
• If new file reference added for test, has is been added to github.com/dataplat/appveyor-lab ?
• Unit test is included
• Documentation
• Build system

As I have to (re-)refactor this command a second time after the first refactoring in 2022, I want to do something new: Have a command with a lot of comments to tell other contributors how and why we do things.

I changed Stop-Function to support -WhatIf. Without that change, the variable is not set and Test-FunctionInterrupt does not work. Then, if the command fails in the begin block, the process block is still executed.

As I'm not a native english speaker, please correct all my mistakes in the new comments.

And there are some "Discussion" comments - which I would like to discuss.

[niphlod]

Had time just to do a first round as an "editor", other things may pop up

[andreasjordan]

Thanks @niphlod for the feedback, just fixed some typos.

One additional point: Pipeline Input. A lot of commands accept pipeline input, most other ...-DbaDb... commands accept database SMOs to be piped in. That would also be my recommendation. But I wanted to get feedback before changing the code.

[niphlod]

on "the pipeline" ... I guess it has not been "declared" a sound/strict rationale behind it.
Prolly the author inserts it the way "it was envisioned" in the first place or it has been added as an additional request. I don't think we should "force" to have all the commands targeting dbs to accept a pipelined "list of smo dbs", nor "force" login-related parameters to accept a "list of smo logins", etc etc etc. tl;dr: I see it as a "nicety" (granted it makes sense for some kind of useful behaviour) rather than an "obligation" to adhere to.

[potatoqualitee]

will merge once approved 👍🏼

[potatoqualitee]

Hell yeah, love that approval. Thank you both so much 🙇🏼