grafana/k6 · error

missing required argument 'text'

Error message

missing required argument 'text'

What it means

Thrown by locator.getByText() in the k6 browser module (internal/js/modules/k6/browser/browser/locator_mapping.go:281). The text argument (string or RegExp matched against element text content) is mandatory; the nullish guard fails the call before parseGetByBaseOptions builds the selector, since there is no way to query 'text of nothing'.

Solutions

1. Pass a string or RegExp: page.locator('ul').getByText('Item 1')
2. Default dynamic values: const label = row.label ?? 'Item 1'
3. If the text is genuinely optional, branch instead of calling: if (label) child = parent.getByText(label)
4. Trace where the variable becomes undefined (console.log or k6 console.debug) and fix the producer

Example fix

// before
const item = page.locator('ul').getByText(getLabel(i)); // getLabel returns undefined for some i

// after
const item = page.locator('ul').getByText(getLabel(i) ?? `Item ${i}`);

const label = getLabel(i) ?? `Item ${i}`;
if (label === undefined || label === null) throw new Error('text is required');
const loc = parent.getByText(label);

function isNonEmptyStringOrRegExp(v) {
  return (typeof v === 'string' && v.length > 0) || v instanceof RegExp;
}
// usage: if (!isNonEmptyStringOrRegExp(label)) throw new Error('text must be a non-empty string or RegExp');

try {
  const loc = parent.getByText(label);
} catch (e) {
  if (/missing required argument 'text'/.test(e.message)) throw new Error(`text missing for row ${i}`);
  throw e;
}

When it happens

Trigger: Calling parent.getByText() with zero arguments; passing undefined/null explicitly; passing a text variable computed from a function that returned undefined (e.g. missing .textContent).

Common situations: Labels/assertion strings read from i18n bundles or data files with missing keys; text extracted from a previous DOM node that did not exist; scripts parameterized so that some rows have no text filter.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• missing required argument 'placeholder'
• missing required argument 'role'
• missing required argument 'testId'
• missing required argument 'text'
• missing required argument 'title'

AI-assisted analysis of grafana/k6@8d06114777 (2026-08-18). Data as JSON: /api/errors/b59456b303b9e34e. Report an issue: GitHub.

Appendix: source

Thrown at internal/js/modules/k6/browser/browser/locator_mapping.go:282

				return nil, errors.New("missing required argument 'role'")
			}
			popts := parseGetByRoleOptions(vu.Context(), opts)

			ml := mapLocator(vu, lo.GetByRole(role.String(), popts))
			return rt.ToValue(ml).ToObject(rt), nil
		},
		"getByTestId": func(testID sobek.Value) (*sobek.Object, error) {
			if k6common.IsNullish(testID) {
				return nil, errors.New("missing required argument 'testId'")
			}
			ptestID := parseStringOrRegex(testID, false)

			ml := mapLocator(vu, lo.GetByTestID(ptestID))
			return rt.ToValue(ml).ToObject(rt), nil
		},
		"getByText": func(text sobek.Value, opts sobek.Value) (*sobek.Object, error) {
			if k6common.IsNullish(text) {
				return nil, errors.New("missing required argument 'text'")
			}
			ptext, popts := parseGetByBaseOptions(vu.Context(), text, true, opts)

			ml := mapLocator(vu, lo.GetByText(ptext, popts))
			return rt.ToValue(ml).ToObject(rt), nil
		},
		"getByTitle": func(title sobek.Value, opts sobek.Value) (*sobek.Object, error) {
			if k6common.IsNullish(title) {
				return nil, errors.New("missing required argument 'title'")
			}
			ptitle, popts := parseGetByBaseOptions(vu.Context(), title, false, opts)

			ml := mapLocator(vu, lo.GetByTitle(ptitle, popts))
			return rt.ToValue(ml).ToObject(rt), nil
		},
		"locator": func(selector string, opts sobek.Value) mapping {
			return mapLocator(vu, lo.Locator(selector, parseLocatorOptions(rt, opts)))
		},

View on GitHub (pinned to 8d06114777)