waitForEvent does not support mapping for event: %q

Error message

waitForEvent does not support mapping for event: %q

What it means

Error "waitForEvent does not support mapping for event: %q" thrown in grafana/k6.

Source

Thrown at internal/js/modules/k6/browser/browser/page_mapping.go:692

			// so that the linter can catch unhandled event types as non-exhaustive switch.
			// Otherwise, we might miss mapping new [PageEvent] types added in the future.
			// This is for keeping events in sync between waitForEvent and page.on.
			mapPageEvent := func(vu moduleVU, pe common.PageEvent) (mapping, error) {
				switch event {
				case common.PageEventConsole:
					return mapConsoleMessage(vu, pe), nil
				case common.PageEventRequest:
					return mapRequestEvent(vu, pe), nil
				case common.PageEventResponse:
					return mapResponseEvent(vu, pe), nil
				case common.PageEventRequestFinished:
					return mapRequestEvent(vu, pe), nil
				case common.PageEventRequestFailed:
					return mapRequestEvent(vu, pe), nil
				case common.PageEventMetric:
					// intentionally left blank
				}
				return nil, fmt.Errorf("waitForEvent does not support mapping for event: %q", event)
			}

			popts, fn, err := parsePageWaitForEventOptions(vu.Context(), opts, p.Timeout())
			if err != nil {
				return nil, fmt.Errorf("parsing waitForEvent options: %w", err)
			}

			ctx := vu.Context()
			tq := vu.get(ctx, p.TargetID())

			return promise(vu, func() (any, error) {
				rpe, err := p.WaitForEvent(event, popts, func(pe common.PageEvent) (bool, error) {
					if fn == nil {
						return true, nil
					}
					return queueTask(ctx, tq, func() (bool, error) {
						m, err := mapPageEvent(vu, pe)
						if err != nil {

View on GitHub (pinned to 93accf6570)

When it happens

Trigger: Thrown at internal/js/modules/k6/browser/browser/page_mapping.go:692 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grafana/k6@93accf6570 (2026-08-15). Data as JSON: /api/errors/ae3df7be34aba89d. Report an issue: GitHub.