Is there a server that would produce both an edit and a command in a single CodeAction?

[bstaletic]

I am updating my client's code action support.
I am unsure how to implement code actions with mixed edit and command in them.
Having a server to test against would be very useful.
If there is such a server, knowing how to trigger this use case would also be appreciated.

[bstaletic]

Another question is:

In the "mixed code action" case, do clients have to apply the edit, send didChange notification(s) and only then execute the command?
Or can clients agreggate the edit with the changes that executing the command produces and only then actually apply?

[HighCommander4]

Clangd doesn't currently use both an edit and a command, but a potential use case for this is discussed in the conversation starting at clangd/clangd#1367 (comment).

[dbaeumer]

If you have both a edit and a command, first the edit should be applied, including sending out change notifications and then the command should be applied.

[puremourning]

If you have both a edit and a command, first the edit should be applied, including sending out change notifications and then the command should be applied.

What is the purpose of this complex feature? What use cases is it for?

[dbaeumer]

• historical reasons
• to trigger API commands if the client supports them (this is client specific)
• to let the server know about the execution of a code action in case there needs to be some follow-up work.

[HighCommander4]

To add to the above, clangd's use case is deferring the expensive computation of a text edit to after a completion item has been selected (so that the computation only has to be done for the selected proposal, not all offered proposals).

[DanTup]

The Dart LSP server sometimes does this when the edits are inlined (because they were already computed), so that the server knows that the action was invoked (for ex. if analytics are enabled, metrics on the number of times each action is used can be collected):

{
	"command": {
		"arguments": [
			{
				"action": "dart.assist.add.typeAnnotation"
			}
		],
		"command": "dart.logAction",
		"title": "Log Action"
	},
	"diagnostics": [],
	"edit": {
		"documentChanges": [/*...*/]
	},
	"kind": "refactor.add.typeAnnotation",
	"title": "Add type annotation"
}

If you want to test with it, this can be triggered by having the code a = 1; in a .dart file and sending a CodeAction request on the a to get the Add type annotation" action. The Dart LSP server is part of the Dart SDK and started with dart language-server`.

[bstaletic]

I have managed to implement this kind of "mixed" code actions.
@DanTup Thanks for pointing me in the Dart direction.
@dbaeumer Thaks for clarifying the client expectation.

[dbaeumer]

I will close the issue since it looks answered to me.