Evaluate `AnnotatedTextEdit` and `ChangeAnnotation#needsConfirmation`

[BoykoAlex]

VScode supports annotated edits which can a common ChangeAnnotation that has needsConfirmation flag. Once the flag is set VSCode shows nice compare and merge UI where user can preview changes and accept/reject them.

This feature needs to be evaluated whether we can take advantage of it as its purpose seem to partially accept changes. Spring Boot version upgrade usually assumes all changes are accepted otherwise code may not compile but there are exceptions from this of course.

[BoykoAlex]

@martinlippert i have put in first trial for this: 1539beb
When recipes are applied via Upgrade Spring Boot Version... or Refactor Spring Boot Project... UI user is prompted to select Apply or Preview changes. Code actions and quick fixes don't have this yet but perhaps it is for the better...
The needsConfirmation flag is say "yes" to a change. If the change has this flag on it is not check-marked in the Refactor Preview. Selecting all changes in the Refactor View is annoying... I wish we could just bring up the Refactor View (i.e. showPreview flag) rather than have needsConfirmation.

[martinlippert]

I tried the initial implementation (latest available pre-release), some initial thoughts:

• I find it somewhat strange to select the Apply or Preview flag when executing the command from the palette (while walking through the quick picks). A more VSCode-natural way would be - at least I think - to present this choice as a popup when the changes have been computed. It would be similar to the initializr integration, where there is a popup showing up once the project got created whether to open the project in a new window or in the existing workspace.
• I agree to your observation about the refactoring preview. It would be nice if the changes would be pre-selected, so that clicking on the individual changes results in a diff view showing up with the actual code changes. At the moment, when you execute the upgrade, you see all those changes (presented in a slightly weird way) in the refactoring preview, then you would like to see the details, you click on a change, and you see exactly nothing in the diff editor, because the change you clicked on is not checked yet.

I think we can try to implement the first part and probably raise an issue against VSCode for the second part to see what the team from VSCode says. Maybe there is a way to turn on this pre-selection.

I also find it a bit weird that there is no "select all" option in the refactoring preview.

[martinlippert]

One more thought: Moving the Apply or Preview choice into the popup that the language server would initiate once the changes are computed would also allow this to appear nicely when executing these things from the quick fixes... :-)

[BoykoAlex]

@martinlippert Hmm... VSCode offers to apply refactoring right away or show the preview first via the UI before the refactoring

Shift-Enter would show preview. This is what i was trying to follow given the UI restrictions we have.

Or you'd still like to try the popup?

[martinlippert]

Or you'd still like to try the popup?

I would like to give it a try. At least for those "larger" changes (like version upgrades, running recipes on the project). So this would split the quick fixes into two categories:

• the ones that execute the upgrade recipes or other recipes on the whole project (show the popup)
• the "small" quick fixes that operate on a specific location (e.g. remove public from bean method) or a single file (do NOT show popup)