garrytan/gstack · error · Error

Unknown viewport flag: ${args[i]}

Error message

Unknown viewport flag: ${args[i]}

What it means

Error "Unknown viewport flag: ${args[i]}" thrown in garrytan/gstack.

Source

Thrown at browse/src/write-commands.ts:517

    }

    case 'viewport': {
      // Parse args: [<WxH>] [--scale <n>]. Either may be omitted, but NOT both.
      let sizeArg: string | undefined;
      let scaleArg: number | undefined;
      for (let i = 0; i < args.length; i++) {
        if (args[i] === '--scale') {
          const val = args[++i];
          if (val === undefined || val === '') {
            throw new Error('viewport --scale: missing value. Usage: viewport [WxH] --scale <n>');
          }
          const parsed = Number(val);
          if (!Number.isFinite(parsed)) {
            throw new Error(`viewport --scale: value '${val}' is not a finite number.`);
          }
          scaleArg = parsed;
        } else if (args[i].startsWith('--')) {
          throw new Error(`Unknown viewport flag: ${args[i]}`);
        } else if (sizeArg === undefined) {
          sizeArg = args[i];
        } else {
          throw new Error(`Unexpected positional arg: ${args[i]}. Usage: viewport [WxH] [--scale <n>]`);
        }
      }

      if (sizeArg === undefined && scaleArg === undefined) {
        throw new Error('Usage: browse viewport [<WxH>] [--scale <n>]  (e.g. 375x812, or --scale 2 to keep current size)');
      }

      // Resolve width/height: either from sizeArg or from current viewport if --scale-only.
      let w: number, h: number;
      if (sizeArg) {
        if (!sizeArg.includes('x')) throw new Error('Usage: browse viewport [<WxH>] [--scale <n>] (e.g., 375x812)');
        const [rawW, rawH] = sizeArg.split('x').map(Number);
        w = Math.min(Math.max(Math.round(rawW) || 1280, 1), 16384);
        h = Math.min(Math.max(Math.round(rawH) || 720, 1), 16384);

View on GitHub (pinned to 94993f7401)

When it happens

Trigger: Thrown at browse/src/write-commands.ts:517 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/d81e4f8b3739052c. Report an issue: GitHub.