Function createLSPClient

src/services/lsp/LSPClient.ts:51–447

(
  serverName: string,
  onCrash?: (error: Error) => void,
)

 *   to propagate crash state so the server can be restarted on next use.
 */
export function createLSPClient(
  serverName: string,
  onCrash?: (error: Error) => void,
): LSPClient {
  // State variables in closure
  let process: ChildProcess | undefined
  let connection: MessageConnection | undefined
  let capabilities: ServerCapabilities | undefined
  let isInitialized = false
  let startFailed = false
  let startError: Error | undefined
  let isStopping = false // Track intentional shutdown to avoid spurious error logging
  // Queue handlers registered before connection ready (lazy initialization support)
  const pendingHandlers: Array<{
    method: string
    handler: (params: unknown) => void
  }> = []
  const pendingRequestHandlers: Array<{
    method: string
    handler: (params: unknown) => unknown | Promise<unknown>
  }> = []

  function checkStartFailed(): void {
    if (startFailed) {
      throw startError || new Error(`LSP server ${serverName} failed to start`)
    }
  }

  return {
    get capabilities(): ServerCapabilities | undefined {
      return capabilities
    },

    get isInitialized(): boolean {
      return isInitialized
    },

    async start(
      command: string,
      args: string[],
      options?: {
        env?: Record<string, string>
        cwd?: string
      },
    ): Promise<void> {
      try {
        // 1. Spawn LSP server process
        process = spawn(command, args, {
          stdio: ['pipe', 'pipe', 'pipe'],
          env: { ...subprocessEnv(), ...options?.env },
          cwd: options?.cwd,
          // Prevent visible console window on Windows (no-op on other platforms)
          windowsHide: true,
        })

        if (!process.stdout || !process.stdin) {
          throw new Error('LSP server process stdio not available')
        }