typescript-lsp

name

typescript-lsp

description

Use the TypeScript language server (`typescript-language-server`) for precise code intelligence in the `clickhouse-js` repository: go-to-definition, find references, hover (type signatures and JSDoc, including `@deprecated` info), workspace-wide symbol search, completions, and per-file type diagnostics. Prefer this over grep when you need to resolve a symbol's actual definition, find all usages of an exported API, or inspect inferred types across the `packages/*` workspaces. The server is preinstalled as a root devDependency — run the repository `setup` skill (`npm install`) first so `node_modules` is populated. Do NOT use this skill for downstream projects that merely depend on `@clickhouse/client`; it is specific to working inside this repo.

TypeScript Language Server in clickhouse-js

typescript-language-server is declared as a root devDependency, so after npm install (see the setup skill) it is available via npx and uses the workspace-local typescript (6.x) compiler, matching CI exactly.

Starting the server

From the repo root:

npx typescript-language-server --stdio

It speaks LSP (JSON-RPC, Content-Length-framed) over stdio. There is no extra configuration: each packages/* workspace, tests/clickhouse-test-runner, examples/node, and examples/web has its own tsconfig.json, and the server picks the nearest one per opened file automatically.

Protocol essentials

1. Send initialize with rootUri/workspaceFolders pointing at the repo root, then the initialized notification.
2. Send textDocument/didOpen with the full file text for every file you want to query (the server reads dependencies from disk on its own; only files you query positions in need to be opened).
3. Positions are 0-based (line and character).

Verified capabilities (typescript-language-server 5.x, TS 6.x)

Request	Notes
textDocument/hover	Returns the full inferred signature + JSDoc markdown
textDocument/definition	Resolves across workspace packages via source, not dist/
textDocument/references	Within the opened file's project
workspace/symbol	e.g. query ClickHouseClient finds class + re-exports
textDocument/completion	Context-aware member completions
Diagnostics	Push only (textDocument/publishDiagnostics notifications, sent ~1–3s after didOpen). The pull textDocument/diagnostic request is not supported (-32601) — wait for the push notification instead.

Tips

• If your environment provides built-in LSP/code-intelligence tooling, point it at npx typescript-language-server --stdio with the repo root as the workspace folder.
• For one-off scripted queries, spawn the server from Node, frame messages with Content-Length: <bytes>\r\n\r\n<json>, and match responses by id.
• A full workspace typecheck is still npm run build && npm run typecheck (build first — some workspaces import compiled dist/ outputs); the LSP is for targeted, interactive queries, not for CI-equivalent validation.