Language server doesn't respond to initialize request properly

[rozaliev]

I'm trying to make language-server work with Helix. But it looks like lsp doesn't respond to initialize request properly before sending its own requests. According to the spec:

Until the server has responded to the initialize request with an InitializeResult, the client must not send any additional requests or notifications to the server. In addition the server is not allowed to send any requests or notifications to the client until it has responded with an InitializeResult, with the exception that during the initialize request the server is allowed to send the notifications window/showMessage, window/logMessage and telemetry/event as well as the window/showMessageRequest request to the client.

Language server: @tailwindcss/language-server@0.0.13
tailwind-language-server --stdio

Expected:

-> {"jsonrpc":"2.0","method":"initialize","params":{ ... },"id":0}
<- {"jsonrpc":"2.0","id":0,"result": { ... }}

Received:

-> {"jsonrpc":"2.0","method":"initialize","params":{ ... },"id":0}
<- {"jsonrpc":"2.0","id":0,"method":"workspace/configuration","params":{"items":[{"section":"editor"}]}}
<- {"jsonrpc":"2.0","id":1,"method":"workspace/configuration","params":{"items":[{"section":"tailwindCSS"}]}}

I would assume that this line is the reason

tailwindcss-intellisense/packages/tailwindcss-language-server/src/server.ts

Line 1655 in 1438300

let globalSettings = await getConfiguration()

And this these are the lines that send requests before the initialize response.

tailwindcss-intellisense/packages/tailwindcss-language-server/src/server.ts

Line 247 in 1438300

let [editor, tailwindCSS] = await Promise.all([

[atihonovschi]

I can confirm absolutely the same behavior. I'm using vim 9.
However the same server binary works well with coc.nvim plugin but is not working with https://github.com/yegappan/lsp.

Looks like 'coc.nvim', 'VS Code' and others just 'supports dynamic registration' here and receive prompt response with caps:

tailwindcss-intellisense/packages/tailwindcss-language-server/src/server.ts

Line 2325 in 1438300

if (supportsDynamicRegistration(connection, params)) {

all others go "long way" with await tw.init() - receiving configuration request instead...

After analysing the code I think that line

tailwindcss-intellisense/packages/tailwindcss-language-server/src/server.ts

Line 2333 in 1438300

await tw.init()

is the source of the bug and should be completely removed, since the init method is called after the connection is initialised from this line -

tailwindcss-intellisense/packages/tailwindcss-language-server/src/server.ts

Line 2351 in 1438300

await tw.init()

The 'yegappan/lsp' logs show the same records as shown above for 'Helix".

The 'coc.nvim' logs however show response correctly received for 'initialize':

[Trace - 20:23:19.544] Sending request 'initialize - (0)'.
Params: {...}


[Trace - 20:23:19.762] Received response 'initialize - (0)' in 219ms.
Result: {
    "capabilities": {
        "textDocumentSync": 1
    }
}


[Trace - 20:23:19.763] Sending notification 'initialized'.
Params: {}


[Trace - 20:23:19.770] Sending notification 'textDocument/didOpen'.
Params: {
    "textDocument": {
        "uri": "file:///home/.../label.component.html",
        "languageId": "html",
        "version": 1,
        "text": "..."
    }
}


[Trace - 20:23:19.770] Received request 'workspace/configuration - (0)'.
Params: {
    "items": [
        {
            "section": "editor"
        }
    ]
}


[Trace - 20:23:19.771] Sending response 'workspace/configuration - (0)'. Processing request took 1ms
Result: [
    {}
]

[atihonovschi]

@rozaliev You may try to use my fork for testing (will require you to build packages lerna run build, set execution permission on the resulting packages/tailwindcss-landuage-server/dist/.../bin/tailwindcss-landuage-server and using path to this executable in your helix lsp config)

[rozaliev]

@atgote thanks, your fork seems to work with Helix, at least for the initialization part and simple HTML editing.

But with custom regex, only completion works and hover doesn't. Here are the weird things I found in the logs:

2023-06-20T11:02:54.772 helix_lsp::transport [INFO] tailwind-hack -> {"jsonrpc":"2.0","method":"initialize","params":{"capabilities":{"general":{"positionEncodings":["utf-8","utf-32","utf-16"]},"textDocument":{"codeAction":{"codeActionLiteralSupport":{"codeActionKind":{"valueSet":["","quickfix","refactor","refactor.extract","refactor.inline","refactor.rewrite","source","source.organizeImports"]}}},"completion":{"completionItem":{"deprecatedSupport":true,"insertReplaceSupport":true,"resolveSupport":{"properties":["documentation","detail","additionalTextEdits"]},"snippetSupport":true,"tagSupport":{"valueSet":[1]}},"completionItemKind":{}},"hover":{"contentFormat":["markdown"]},"inlayHint":{"dynamicRegistration":false},"publishDiagnostics":{"versionSupport":true},"rename":{"dynamicRegistration":false,"honorsChangeAnnotations":false,"prepareSupport":true},"signatureHelp":{"signatureInformation":{"activeParameterSupport":true,"documentationFormat":["markdown"],"parameterInformation":{"labelOffsetSupport":true}}}},"window":{"workDoneProgress":true},"workspace":{"applyEdit":true,"configuration":true,"didChangeConfiguration":{"dynamicRegistration":false},"executeCommand":{"dynamicRegistration":false},"inlayHint":{"refreshSupport":false},"symbol":{"dynamicRegistration":false},"workspaceEdit":{"documentChanges":true,"failureHandling":"abort","normalizesLineEndings":false,"resourceOperations":["create","rename","delete"]},"workspaceFolders":true}},"clientInfo":{"name":"helix","version":"23.05"},"initializationOptions":{"tailwindCSS":{"experimental":{"classRegex":["class: \"(.*)\""]},"includedLanguages":{"rust":"html"}}},"processId":60856,"rootPath":"/mypath/diox_1","rootUri":"file:///mypath/diox_1","workspaceFolders":[{"name":"diox_1","uri":"file:///mypath/diox_1"}]},"id":0}


2023-06-20T11:02:55.493 helix_term::application [DEBUG] received editor event: LanguageServerMessage((0, MethodCall(MethodCall { jsonrpc: Some(V2), method: "client/registerCapability", params: Map({"registrations": Array [Object {"id": String("f96c2630-3ce7-4ec3-8b5d-d51b667f4dee"), "method": String("textDocument/hover"), "registerOptions": Object {"documentSelector": Null}}, Object {"id": String("c07e4872-a44f-4098-90d1-0597b761c22b"), "method": String("textDocument/documentColor"), "registerOptions": Object {"documentSelector": Null}}, Object {"id": String("6f3342de-6b09-4b1e-a069-51788dd061e6"), "method": String("textDocument/codeAction"), "registerOptions": Object {"documentSelector": Null}}, Object {"id": String("349075c1-391a-4393-847a-2ab7b1616e2e"), "method": String("textDocument/documentLink"), "registerOptions": Object {"documentSelector": Null}}, Object {"id": String("8db816d3-1c8c-41a6-a95e-75622fb8d660"), "method": String("textDocument/completion"), "registerOptions": Object {"documentSelector": Null, "resolveProvider": Bool(true), "triggerCharacters": Array [String("\""), String("'"), String("`"), String(" "), String("."), String("("), String("["), String("!"), String("/"), String(":")]}}]}), id: Num(4) })))

2023-06-20T11:02:55.493 helix_term::application [WARN] Ignoring a client/registerCapability request because dynamic capability registration is not enabled. Please report this upstream to the language server

I'm not sure if this is directly related to hover, because it works for HTML and shows similar errors. But it definitely seems like a bug, dynamicRegistration is clearly set to false by the client and is ignored.

[rozaliev]

I think I figured out how to make hover work with custom regex, but I'm not sure how to proceed since I'm not really familiar with Tailwind codebase and there are no tests.

I assume that somewhere around here should be code that handles includeLanguages and classRegex

tailwindcss-intellisense/packages/tailwindcss-language-service/src/util/find.ts

Line 446 in 1438300

if (isCssContext(state, doc, position)) {

I've added this line to test things out:

else {
    classNames = await findClassNamesInRange(state, doc, searchRange, 'html', true)
}

Notice the last argument, which sets includeCustom to true and enables classRegex

Everything seems to work with this change.

[bradlc]

This should be fixed by #803 but please open a new issue if you're still running into problems 👍

We now automatically publish insiders releases for @tailwindcss/language-server, so until we publish a new latest release that's the one to try out (npm install @tailwindcss/language-server@insiders)