Support for inlay hints in extensions

[uargos]

Hello,

I am trying to integrate the Lean language in zed with an extension. It is the first time I tinker with LSP, so I may be missing some context here.

AFAICT, the lean language server support inlay hints (see https://github.com/leanprover/lean4/blob/45d39422bc57fada6bf281cf2119fdd99de14343/src/Lean/Server/Watchdog.lean#L1099-L1101). Unfortunately, it seems that the capability is not detected by zed:

* Capabilities: {
  "textDocumentSync": {
    "openClose": true,
    "change": 2,
    "willSave": false,
    "willSaveWaitUntil": false,
    "save": {
      "includeText": true
    }
  },
  "hoverProvider": true,
  "completionProvider": {
    "resolveProvider": true,
    "triggerCharacters": [
      "."
    ]
  },
  "definitionProvider": true,
  "typeDefinitionProvider": true,
  "referencesProvider": true,
  "documentHighlightProvider": true,
  "documentSymbolProvider": true,
  "workspaceSymbolProvider": true,
  "codeActionProvider": {
    "codeActionKinds": [
      "quickfix",
      "refactor"
    ],
    "workDoneProgress": false,
    "resolveProvider": true
  },
  "renameProvider": {
    "prepareProvider": true
  },
  "foldingRangeProvider": true,
  "declarationProvider": true,
  "callHierarchyProvider": true,
  "semanticTokensProvider": {
    "legend": {
      "tokenTypes": [
        "keyword",
        "variable",
        "property",
        "function",
        "namespace",
        "type",
        "class",
        "enum",
        "interface",
        "struct",
        "typeParameter",
        "parameter",
        "enumMember",
        "event",
        "method",
        "macro",
        "modifier",
        "comment",
        "string",
        "number",
        "regexp",
        "operator",
        "decorator",
        "leanSorryLike"
      ],
      "tokenModifiers": [
        "declaration",
        "definition",
        "readonly",
        "static",
        "deprecated",
        "abstract",
        "async",
        "modification",
        "documentation",
        "defaultLibrary"
      ]
    },
    "range": true,
    "full": true
  }
}

I tried to look into other extensions, to see if anything special was done regarding inlay hints, but I could not find anything.

Is there anything I should do the inlay hints to be supported ?

[uargos]

I did not notice on the blame, but I was on the edge of the lean lsp development there. Inlay hints are now available on nightly, and everything is plugging correctly.