garrytan/gstack · error · Error

Expected @ref, got CSS selector: ${url}

Error message

Expected @ref, got CSS selector: ${url}

What it means

Error "Expected @ref, got CSS selector: ${url}" thrown in garrytan/gstack.

Source

Thrown at browse/src/write-commands.ts:1156

      const parts = ['Screenshot saved'];
      if (doCleanup) parts.push('(cleaned)');
      if (scrollTo) parts.push(`(scrolled to: ${scrollTo})`);
      parts.push(`: ${outputPath}`);
      return parts.join(' ');
    }

    case 'download': {
      if (args.length === 0) throw new Error('Usage: download <url|@ref> [path] [--base64] [--navigate]');
      const isBase64 = args.includes('--base64');
      const useNavigate = args.includes('--navigate');
      const filteredArgs = args.filter(a => a !== '--base64' && a !== '--navigate');
      let url = filteredArgs[0];
      const outputPath = filteredArgs[1];

      // Resolve @ref to element src
      if (url.startsWith('@')) {
        const resolved = await bm.resolveRef(url);
        if (!('locator' in resolved)) throw new Error(`Expected @ref, got CSS selector: ${url}`);
        const locator = resolved.locator;
        const tagName = await locator.evaluate(el => el.tagName.toLowerCase());
        if (tagName === 'img') {
          url = await locator.evaluate(el => {
            const img = el as HTMLImageElement;
            return img.currentSrc || img.src || img.getAttribute('data-src') || '';
          });
        } else if (tagName === 'video') {
          url = await locator.evaluate(el => (el as HTMLVideoElement).currentSrc || (el as HTMLVideoElement).src || '');
        } else if (tagName === 'audio') {
          url = await locator.evaluate(el => (el as HTMLAudioElement).currentSrc || (el as HTMLAudioElement).src || '');
        } else {
          // Try src attribute on any element
          url = await locator.evaluate(el => el.getAttribute('src') || '');
        }
        if (!url) throw new Error(`Could not extract URL from ${filteredArgs[0]} (${tagName})`);
      }

View on GitHub (pinned to 94993f7401)

When it happens

Trigger: Thrown at browse/src/write-commands.ts:1156 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of garrytan/gstack@94993f7401 (2026-08-12). Data as JSON: /api/errors/1d933caa8cb2d23b. Report an issue: GitHub.