grafana/k6 · error

parsing select options values

Error message

parsing select options values: %w

What it means

Thrown when the `values` argument of `frame.selectOption(selector, values, opts)` cannot be converted by ConvertSelectOptionValues. Accepted shapes: a single string, a single object {value?, label?, index?}, an ElementHandle, or an array mixing strings and such objects. Rejections: array items that are numbers/booleans/null ('options: expected string or object, got %T'), value/label not strings ('options[value]: expected string, got %T'), index not an integer ('options[index]: expected int, got %T'), or a top-level unsupported type like a number ('options: unsupported type').

Solutions

1. Wrap numeric selections in objects: [{ index: 1 }] instead of [1]
2. Ensure value/label are strings and index is an integer
3. Validate/normalize the values array before the call when it comes from external data

Example fix

// before
await frame.selectOption('#qty', [2, { value: 'xl' }]);

// after
await frame.selectOption('#qty', [{ index: 2 }, { value: 'xl' }]);

function normalizeSelectValues(values) {
  const arr = Array.isArray(values) ? values : [values];
  return arr.map(v => {
    if (typeof v === 'string') return v;
    if (v && typeof v === 'object' && !Array.isArray(v)) {
      if (v.value !== undefined && typeof v.value !== 'string') throw new Error('value must be a string');
      if (v.label !== undefined && typeof v.label !== 'string') throw new Error('label must be a string');
      if (v.index !== undefined && !Number.isInteger(v.index)) throw new Error('index must be an integer');
      return v;
    }
    if (typeof v === 'number') return { index: v };
    throw new Error(`unsupported select option value: ${JSON.stringify(v)}`);
  });
}

function isSelectOptionValue(v) {
  if (typeof v === 'string') return true;
  if (v == null || typeof v !== 'object' || Array.isArray(v)) return false;
  const { value, label, index } = v;
  return (value === undefined || typeof value === 'string') &&
         (label === undefined || typeof label === 'string') &&
         (index === undefined || Number.isInteger(index));
}

try {
  await frame.selectOption(sel, values, opts);
} catch (e) {
  if (String(e).includes('parsing select options values')) {
    console.error('values must be string | {value?,label?,index?} | ElementHandle, or an array of these');
    throw e;
  }
  throw e;
}

When it happens

Trigger: `frame.selectOption('#s', [1, 2])` (numeric indexes must be objects: [{index: 1}]); `frame.selectOption('#s', [{ value: 42 }])`; `frame.selectOption('#s', true)`; float index `{ index: 1.5 }`.

Common situations: Porting from Playwright where numbers in arrays are also rejected — but developers commonly build option arrays dynamically from JSON data where numbers sneak in; passing booleans or null from loose data parsing.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• parsing select option options
• parsing select option values
• an error occurred communicating with k6 Cloud
• " " attribute is only supported for roles: "`).join(", ")}
• " " does not support " " matcher

AI-assisted analysis of grafana/k6@8d06114777 (2026-08-18). Data as JSON: /api/errors/fc225a29c8309c85. Report an issue: GitHub.

Appendix: source

Thrown at internal/js/modules/k6/browser/browser/frame_mapping.go:338

		},
		"press": func(selector, key string, opts sobek.Value) (*sobek.Promise, error) {
			popts, err := parseFramePressOptions(rt, opts, f.Timeout())
			if err != nil {
				return nil, fmt.Errorf("parse press options of selector %q on key %q: %w", selector, key, err)
			}
			return promise(vu, func() (any, error) {
				return nil, f.Press(selector, key, popts) //nolint:wrapcheck
			}), nil
		},
		"selectOption": func(selector string, values sobek.Value, opts sobek.Value) (*sobek.Promise, error) {
			popts, err := parseFrameSelectOptionOptions(rt, opts, f.Timeout())
			if err != nil {
				return nil, fmt.Errorf("parsing select option options: %w", err)
			}

			convValues, err := ConvertSelectOptionValues(rt, values)
			if err != nil {
				return nil, fmt.Errorf("parsing select options values: %w", err)
			}

			return promise(vu, func() (any, error) {
				return f.SelectOption(selector, convValues, popts) //nolint:wrapcheck
			}), nil
		},
		"setChecked": func(selector string, checked bool, opts sobek.Value) (*sobek.Promise, error) {
			popts, err := parseFrameCheckOptions(rt, opts, f.Timeout())
			if err != nil {
				return nil, fmt.Errorf("parsing frame set check options: %w", err)
			}

			return promise(vu, func() (any, error) {
				return nil, f.SetChecked(selector, checked, popts) //nolint:wrapcheck
			}), nil
		},
		"setContent": func(html string, opts sobek.Value) (*sobek.Promise, error) {
			popts, err := parseFrameSetContentOptions(rt, opts, f.Page().NavigationTimeout())

View on GitHub (pinned to 8d06114777)