Class TerminalProcess

src/targets/node/program.ts:125–195

 * Program created from a subprocess.
 */
export class TerminalProcess implements IProgram {
  /**
   * How often to check and see if the process exited.
   */
  private static readonly terminationPollInterval = 1000;

  /**
   * How often to check and see if the process exited after we send a close signal.
   */
  private static readonly killConfirmInterval = 200;

  private didStop = false;
  private onStopped!: (killed: boolean) => void;
  public readonly stopped = new Promise<IStopMetadata>(
    resolve => (this.onStopped = killed => {
      this.didStop = true;
      resolve({ code: 0, killed });
    }),
  );
  private liveness?: PidLiveness;

  constructor(
    private readonly terminalResult: Dap.RunInTerminalResult,
    private readonly logger: ILogger,
    private readonly killBehavior: KillBehavior,
  ) {
    if (terminalResult.processId) {
      this.liveness = new PidLiveness(
        terminalResult.processId,
        this.onStopped,
        TerminalProcess.terminationPollInterval,
      );
    }
  }

  public gotTelemetery({ processId }: IProcessTelemetry) {
    if (this.didStop) {
      killTree(processId, this.logger, this.killBehavior);
      return; // to avoid any races
    }

    this.liveness ??= new PidLiveness(processId, this.onStopped, 1000);
  }

  public stop(): Promise<IStopMetadata> {
    if (this.didStop) {
      return this.stopped;
    }
    this.didStop = true;

    // If we're already polling some process ID, kill it and accelerate polling
    // so we can confirm it's dead quickly.
    if (this.liveness) {
      killTree(this.liveness.pid, this.logger, this.killBehavior);
      this.liveness.updateInterval(TerminalProcess.killConfirmInterval);
    } else if (this.terminalResult.shellProcessId) {
      // If we had a shell process ID, well, that's good enough.
      killTree(this.terminalResult.shellProcessId, this.logger, this.killBehavior);