Tooling — LSP, Formatter, VS Code

Tulpar ships its own editor tooling — no separate “language plugin” project to clone, no node-based shim. Three pieces:

1. tulpar --lsp — a Language Server Protocol implementation in C++ that any LSP-aware editor can spawn.
2. tulpar fmt — a gofmt-style idempotent formatter.
3. VS Code extension — pre-configured client that wraps both.

Language Server (tulpar --lsp)

Speaks the full LSP base protocol over stdio JSON-RPC. Capabilities advertised today:

Capability	What it gives you
textDocument/publishDiagnostics	Parser + codegen errors, structured ranges, did-you-mean hints.
textDocument/hover	Function signatures + leading-comment doc strings (user funcs + 80+ builtins).
textDocument/completion	User functions, builtins, keywords, lib modules.
textDocument/definition	Jump from a call site to the declaration.
textDocument/references	Find every call site of a symbol.
textDocument/rename	Atomic rename across declaration + every call.

Diagnostics use a process-global “structured sink” — the same Rust-style caret-and-hint output the CLI prints, but emitted as LSP Diagnostic objects with proper range, severity, and source: "tulpar".

Formatter (tulpar fmt)

tulpar fmt path/to/file.tpr            # print formatted version to stdout
tulpar fmt path/to/file.tpr --write    # rewrite the file in place

Two passes:

Indentation pass — based on { / } brace depth. 4-space indent. Closing braces line up with their opener. Trailing whitespace stripped. Runs of 2+ blank lines collapsed to 1. Exactly one trailing newline.

Token-spacing pass — preserves string literal and comment content unchanged, normalises everything else:

• , and ;: no space before, exactly one after (unless followed by a closer).
• : (return type / object key): no space before, one after.
• Binary operators (+, -, *, /, ==, !=, <=, >=, &&, ||, += …): exactly one space on each side.
• Unary -: kept tight (-x, return -1).
• ( and [: no padding inside.
• Keywords: if(...) → if (...), }else{ → } else {, try{}catch(e){}finally{} all spaced.

Idempotent: fmt(fmt(s)) == fmt(s).

VS Code extension

Install the bundled .vsix (search “Tulpar” once it’s on the marketplace):

code --install-extension vscode-tulpar-0.3.0.vsix

The extension auto-spawns tulpar --lsp per workspace and forwards every LSP capability above. It also adds:

• Status bar buttons: ▶ Tulpar Run, 📦 Tulpar Build.
• Commands: Tulpar: Run File, Tulpar: Build (AOT), Tulpar: Open REPL, …
• 30+ snippets covering Wings, ORM, http_client, OpenAPI, regex, datetime, the package manifest, and more.
• Syntax highlighting for the full Tulpar grammar including the typed-return form.

When you edit tulpar.executablePath or toggle tulpar.diagnostics.enabled, the extension restarts the LSP automatically — no window reload needed.

Editors other than VS Code

tulpar --lsp is a plain stdio LSP server. To use it from Neovim, Emacs, JetBrains, Sublime, or anything LSP-aware, point the editor’s language-client config at tulpar --lsp and set the file pattern to *.tpr. Example for Neovim’s built-in LSP:

vim.lsp.config('tulpar', {
  cmd = { 'tulpar', '--lsp' },
  filetypes = { 'tulpar' },
  root_markers = { 'tulpar.toml', '.git' },
})
vim.lsp.enable('tulpar')