fix: should check type of folders

[Shane-XB-Qian]

closes #516

[skovhus]

In which case is folders not an array? What is it?

I'm asking as the type signature here explicitly says that it should always be an array of LSP.WorkspaceFolder

[Shane-XB-Qian]

according to rough looking to lsp specification,
looks it said It can be 'null' if the client supports workspace folders but none are configured.

[skovhus]

That case is handled here: https://github.com/bash-lsp/bash-language-server/blob/main/server/src/server.ts#L92

[Shane-XB-Qian]

the problem looks was the previous statement before L92.

[Shane-XB-Qian]

      const folders = this.clientCapabilities.workspace?.workspaceFolders
        ? await connection.workspace.getWorkspaceFolders()
        : []
      const lintDiagnostics = await this.linter.lint(change.document, folders || [])

1. this.clientCapabilities.workspace?.workspaceFolders this got from initialize and that is true.
2. however await connection.workspace.getWorkspaceFolders() looks send workspace/workspaceFolders to lsp client, but got {'id': 0, 'jsonrpc': '2.0', 'result': {}}
3. so that folders looks was a {} ?! <--------- !!!

so the problem is:

1. could it get from this.clientCapabilities.workspaceFolders when/if this.clientCapabilities.workspace?.workspaceFolders is true?
2. should lsp client response with result: ........ something else or could be {}?
3. anyway, {} perhaps that's the direct problem.

[Shane-XB-Qian]

and looks others lsp server, i saw they just get workspaces folders from clientCapabilities.workspaceFolders, did not send/get from lsp workspace/workspaceFolders method.

[Shane-XB-Qian]

@skovhus that should be a bug (or un-impl feature) of lsp client, i've opened a pr to correct/impl that.
// see yegappan/lsp#114

// but this pr to bash lsp server, perhaps should be better merged too, since varied lsp client may send others type of folders var.

[skovhus]

but this pr to bash lsp server, perhaps should be better merged too, since varied lsp client may send others type of folders var.

We shouldn't extend the LSP server here to support faulty clients – we want to follow the LSP standard. But thanks for fixing yegappan/lsp#114

I'm closing this for now, but thanks for looking into it.