[Language Server]

PYNE Language Server Protocol surface — diagnostics, completion, hover, navigation, formatting, and editor clients.

Language Server

The PYNE Language Server is the editor-facing half of the evaluation stack: a pygls process that speaks LSP over STDIO (or TCP in tooling), parses Pine with the same ANTLR4 → ASDL pipeline as the runtime, and never requires a proprietary chart host.

Abstract

Editors want static intelligence at typing cadence. Evaluation over OHLCV is dynamic and bar-loop expensive. PYNE therefore splits the stack:

Process	Cadence	Shared substrate
LSP (`pynescript-lsp`)	keystroke / open / save	parse, lint, unparse, builtin metadata
Pro API (`backend.app`)	request / batch	parse, evaluate, plots / events
CLI / library	batch / embed	same AST + evaluator

The LSP publishes diagnostics from the linter and parse errors, completes and hovers from Fernet-ready builtin metadata, navigates user symbols via AST visitors, and formats by round-tripping through the unparser. Feature modules live under src/pynescript/langserver/features/; the VS Code extension and clients/ configs are thin protocol hosts.

Conceptual model

Invariant: open/change/close always re-parse and re-lint the in-memory buffer. Features that need an AST re-parse on demand if the workspace cache is missing source.

Interface surface

Capability	LSP method(s)	Module
Sync	`textDocument/didOpen	didChange
Diagnostics (push + pull)	`publishDiagnostics`, `textDocument/diagnostic`	`workspace.py`, `features/diagnostics.py`
Completion (+ resolve)	`textDocument/completion`, `completionItem/resolve`	`features/completion.py`
Hover	`textDocument/hover`	`features/hover.py`
Definition / references	`textDocument/definition`, `textDocument/references`	`definitions.py`, `references.py`
Symbols	`textDocument/documentSymbol`, `workspace/symbol`	`symbols.py`, `server.py`
Formatting	`textDocument/formatting`, `rangeFormatting`	`features/formatting.py`
Inlay hints	`textDocument/inlayHint`	`features/inlay_hints.py`
Semantic tokens	`textDocument/semanticTokens/full`	`features/semantic_tokens.py` (stub data)

Declared capabilities: src/pynescript/langserver/config.py (get_server_capabilities).

Internals

Path	Role
`src/pynescript/langserver/server.py`	`PynescriptLanguageServer`, method registration
`src/pynescript/langserver/workspace.py`	Document map, incremental edits, parse+lint
`src/pynescript/langserver/config.py`	ServerCapabilities
`src/pynescript/langserver/features/*`	Per-method handlers
`src/pynescript/langserver/providers/*`	Metadata + completion builders
`src/pynescript/langserver/__main__.py`	STDIO entry (`pynescript-lsp`)
`vscode-extension/`	Language client + TextMate grammar
`clients/`	Neovim, Zed, Emacs, Helix snippets

Console scripts are separate: pynescript (Click CLI) vs pynescript-lsp (pygls). Do not conflate them — see architecture.

Tracks in this tab

Architecture — server lifecycle, workspace, capabilities
Diagnostics through Inlay hints — feature manuals
Builtin metadata — generation + Fernet .enc / CRYPTO_KEY
VS Code extension — client packaging
Clients — Neovim, Zed, Emacs, Helix, Sublime