vr: restart the workflow with no changes according to user prompt

[oliver-sanders]

• Closes cylc vr - restart with no changes? #6261
• If there are no changes to reinstall AND the workflow is stopped, rather than just exiting, the cylc vr command will now prompt the user to give them the option of restarting the workflow.
• This makes them aware there are no changes to reinstall (which may be an error on their part) but still gives them the option of restart without having to edit or rerun the command.

An odd feature to introduce at a bugfix release, however, it's kinda a UX type issue so it might make sense.

Check List

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Applied any dependency changes to both setup.cfg (and conda-environment.yml if present).
• Tests are included (or explain why tests are not needed).
• Changelog entry included if this is a change that can affect users
• Cylc-Doc pull request opened if required at cylc/cylc-doc/pull/XXXX.
• If this is a bug fix, PR should be raised against the relevant ?.?.x branch.

[hjoliver]

(Looks good, but I haven't done a proper review yet).

[oliver-sanders]

(rebased)

[oliver-sanders]

(rebased)

[wxtim]

Alles Gut!

[hjoliver]

I'm not sure the logic is quite right here.

[hjoliver]

Suggested change

	f'{NO_CHANGES_STR}: No reinstall or'
	f'{NO_CHANGES_STR}: no'

The STR already says that no reinstall is needed.

[hjoliver]

no changes, workflow running

$  cylc vr twt 
...
WARNING - No changes to reinstall: No reinstall or reload required. ✔️ 

• good: warns there are no changes, does nothing

$ cylc vr twt --yes
...
# no warning that there are no changes to reinstall ❌ 
Successfully reinstalled.  ❌ 

• use of --yes should not make any difference here as there is no prompt to respond to
• there are no changes, so reinstalling and reloading is pointless

no changes, workflow stopped

$ cylc vr twt
...
WARNING - No changes to reinstall ✔️ 
Restart anyway? [y/n]  ✔️ 

• good: warns there are no changes to reinstall, asks if we want to restart anyway

$ cylc vr twt --yes
...
Successfully reinstalled. ❌ 
$ cylc play twt ✔️ 

• we should warn there are no changes, and not do a pointless reinstall
• (--yes is for the "restart anyway" prompt)

[oliver-sanders]

I think that behaviour is as intended (and mostly as before), the --yes argument is not just for the restart-anyway prompt, it also behaves like --force.

I'm guessing you would rather have two separate options for these?

Either way, bumping.

[hjoliver]

I think that behaviour is as intended (and mostly as before), the --yes argument is not just for the restart-anyway prompt, it also behaves like --force.

1. Command help only says: --yes [reinstall] Skip interactive prompts.
2. I'm not aware of any precedent for --yes behaving like --force, so that's a bit surprising
3. What's the point of supporting forced reinstall when we know there are no changes to update? It can't make any difference.

I'm guessing you would rather have two separate options for these?

Not unless you have a good argument for 3. above - is there any need for forced reinstall of no changes? If there is a need, then yes we should have a separate --force option.

BTW, --force could possibly be taken to imply --yes but not vice versa IMO.