I’ve been playing around with the LanguageClient interface to implement Ruff’s native language server support into my extension but faced the following error:
Ruff connection closed unexpectedly: typeMismatch(NovaFoundation.LSP.ServerCapabilities.NotebookDocumentSync.NotebookSelector.DocumentFilter, Swift.DecodingError.Context(codingPath: [CodingKeys(stringValue: "result", intValue: nil), CodingKeys(stringValue: "capabilities", intValue: nil), CodingKeys(stringValue: "notebookDocumentSync", intValue: nil), CodingKeys(stringValue: "notebookSelector", intValue: nil), _JSONKey(stringValue: "Index 0", intValue: 0)], debugDescription: "Expected NotebookDocumentFilter or String.", underlyingError: nil))
In other words, it expects items of the result.capabilities.notebookDocumentSync.notebookSelector array to have the first field with a string or NotebookDocumentFilter value all the time. So, it always expects the notebook field.
The original RPC response was this (truncated a bit):
{
"jsonrpc" : "2.0",
"result" : {
"serverInfo" : {
"version" : "0.6.1",
"name" : "ruff"
},
"capabilities" : {
"notebookDocumentSync" : {
"save" : false,
"notebookSelector" : [
{
"cells" : [
{
"language" : "python"
}
]
}
]
},
…
},
…
},
"id" : 0
}
I suspect Nova’s expectations do not correlate with the LSP spec, where objects of the notebookSelector array easily may have only the cells field.
Please correct me if I’m wrong here. It doesn’t look like other editors with LSP have this problem, and it’s an issue on Ruff’s end.