Class TTYWindowRenderer

packages/cli/src/tty-renderer.ts:29–186

 * forwards all other intercepted `stdout` and `stderr` logs above it.
 */
export class TTYWindowRenderer {
  private options: Required<Options>;
  private streams!: Record<StreamType, Writable['write']>;
  private buffer: { type: StreamType; message: string }[] = [];
  private renderInterval: NodeJS.Timeout | undefined = undefined;

  private windowHeight = 0;
  private finished = false;
  private cleanups: (() => void)[] = [];

  constructor(options: Options) {
    this.options = {
      interval: DEFAULT_RENDER_INTERVAL,
      ...options,
    };

    this.streams = {
      output: options.outputStream.write.bind(options.outputStream),
      error: options.errorStream.write.bind(options.errorStream),
    };

    this.cleanups.push(
      this.interceptStream(process.stdout, 'output'),
      this.interceptStream(process.stderr, 'error'),
    );

    restoreCursor();
    this.write(HIDE_CURSOR, 'output');

    this.start();
  }

  start() {
    this.finished = false;
    this.renderInterval = setInterval(
      () => this.flushBuffer(),
      this.options.interval,
    );
  }

  stop() {
    this.flushBuffer();
    // this.clearWindow();
    this.write(SHOW_CURSOR, 'output');
    this.cleanups.splice(0).map((fn) => fn());
    clearInterval(this.renderInterval);
  }

  /**
   * Write all buffered output and stop buffering.
   * All intercepted writes are forwarded to actual write after this.
   */
  finish() {
    this.finished = true;
    this.flushBuffer();
    clearInterval(this.renderInterval);
  }