Format on save with gleam lsp

[miquecg]

Hi,

I'm fiddling with gleam for the first time and it recently got a Language Server with rather limited set of features for now. It does work with following configuration:

  "languageserver": {
    "gleam": {
      "command": "gleam",
      "args": ["lsp"],
      "filetypes": ["gleam"],
      "rootPatterns": ["gleam.toml", ".git"]
    }
  }

Formatter works just fine. For instance I have this binding for the task: command! -nargs=0 Format :call CocAction('format'), or if I use CocCommand editor.action.formatDocument, but automatic formatting on save apparently doesn't.

  "coc.preferences.formatOnSaveFiletypes": [
    "c",
    "elixir",
    "gleam"
  ]

Am I missing something?

[chemzqm]

Could be timeout, checkout https://github.com/neoclide/coc.nvim/wiki/Debug-language-server#using-output-channel

[miquecg]

Look at this init response:

Received response 'initialize - (0)' in 86ms.
Result: {
    "capabilities": {
        "definitionProvider": true,
        "documentFormattingProvider": true,
        "hoverProvider": true,
        "textDocumentSync": {
            "change": 1,
            "save": {
                "includeText": false # could it be this setting ??
            }
        }
    }
}

[chemzqm]

"includeText": false # could it be this setting ??

No, need full output.

[miquecg]

You mean that I post the full init response?

[chemzqm]

Verbose output from language server

[zweimach]

It looks like gleam lsp gives the full formatted text instead of the diff for each change.
This is the output of a single space change.

[Trace - 4:24:47 PM] Received response 'textDocument/formatting - (3)' in 2ms.
Result: [
    {
        "newText": "import gleam/io\n\nfn add(x: Int, y: Int) -> Int {\n  x + y\n}\n\npub fn main() {\n  io.println(\"Hello from wiyata!\")\n  let a = add(12, 12)\n}\n",
        "range": {
            "end": {
                "character": 0,
                "line": 4294967295
            },
            "start": {
                "character": 0,
                "line": 0
            }
        }
    }
]