Create commands usable by vim

[jclsn]

So from my research the current commands supported by Neovim, send customs requests to the LSP. This would be in theory be possible from vim as well, but since there is a variety of LSP clients for vim, it would have get implemented for each on of those. I saw that pkl-lsp requested a sync in a prompt, which was successful. Currently there is no way to trigger this manually though.

One solution would be making use of the pkl binary to handle these things. Would it be possible to recreate e.g. :pkl sync-projects with pkl project resolve?

[bioball]

Not really; the syncProjects command is something that only the LSP cares about.

Have you tried integrating any of the existing Vim LSP libraries with pkl-lsp? You'd need to implement this logic:

pkl-neovim/lua/pkl-neovim.lua

Lines 129 to 135 in d7cc92d

	---Scans the workspace directories for PklProject files, and creates a graph of dependencies.
	function M.sync_projects()
	local client = get_or_start_lsp_client()
	assert(client, "No Pkl LSP instance found attached to the current buffer")
	local buf = api.nvim_get_current_buf()
	client:request("pkl/syncProjects", nil, function() end, buf)
	end

[jclsn]

I already found those. I just don't know if these custom requests are supported by the client. There are also many LSP clients for vim

https://github.com/ycm-core/YouCompleteMe
https://github.com/neoclide/coc.nvim
https://github.com/prabirshrestha/vim-lsp
https://github.com/yegappan/lsp

Which vary in configurability. I don't think implementing commands for all of them makes sense.

I am using yegappan/lsp, which is written in vim9script and quite performant. There was prompt that the language server wants to sync the projects and I could do this successfully. So far the client only supports code actions afaik.

[jclsn]

So I was able to send custom requests via yegappan/lsp. Syncing works well, but package downloads fail. Not sure about the format here

07/18/25 00:02:34: Sent {'method': 'pkl/downloadPackage', 'params': 'pkg.pkl-lang.org/pkl-pantry/icalendar'}
07/18/25 00:02:34: Received {'id': 2, 'jsonrpc': '2.0', 'error': {'data': 'java.lang.NullPointerException
	at org.pkl.lsp.PklLspServer.downloadPackage(PklLspServer.kt:131)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
	at java.base/java.lang.reflect.Method.invoke(Method.java:565)
	at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.lambda$recursiveFindRpcMethods$0(GenericEndpoint.java:65)
	at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.request(GenericEndpoint.java:128)
	at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.handleRequest(RemoteEndpoint.java:271)
	at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.consume(RemoteEndpoint.java:201)
	at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.handleMessage(StreamMessageProducer.java:185)
	at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.listen(StreamMessageProducer.java:97)
	at org.eclipse.lsp4j.jsonrpc.json.ConcurrentMessageProcessor.run(ConcurrentMessageProcessor.java:114)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:545)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:328)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1095)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:619)
	at java.base/java.lang.Thread.run(Thread.java:1447)
', 'code': -32603, 'message': 'Internal error.'}}

[bioball]

That looks almost right, except the package URI is incorrect. Should be something like package://pkg.pkl-lang.org/pkl-pantry/icalendar@0.1.1.

[jclsn]

Yeah, that doesn't throw an error, but I am also not getting a confirmation that it worked or where it has been downloaded to. Doesn't seem like this is supported by the Neovim plugin either, so I guess pkl/syncProjects will do for now?