grafana/k6 · error

evaluating handle for element

Error message

evaluating handle for element: %w

What it means

Wrap of an ExecutionContext.EvalHandle failure in BaseJSHandle.EvaluateHandle: like Evaluate, the page function runs in the browser with the handle as first argument, but the result is expected to be a new remote object wrapped as a JSHandle. The wrapped error indicates the evaluation threw in the page (exception or syntax error), or the result could not be materialized as a handle (e.g., the function returned a primitive that cannot be referenced as a remote object).

Solutions

1. Ensure the page function returns an object or DOM node rather than a primitive
2. Check the function for runtime exceptions by testing it in devtools
3. Re-acquire the source handle if navigation may have invalidated its execution context

When it happens

Trigger: Thrown at internal/js/modules/k6/browser/common/js_handle.go:151 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grafana/k6@01ffac6f24 (2026-08-18). Data as JSON: /api/errors/ac246389415e1c55. Report an issue: GitHub.

Appendix: source

Thrown at internal/js/modules/k6/browser/common/js_handle.go:151

}

// Evaluate will evaluate provided page function within an execution context.
func (h *BaseJSHandle) Evaluate(pageFunc string, args ...any) (any, error) {
	args = append([]any{h}, args...)
	res, err := h.execCtx.Eval(h.ctx, pageFunc, args...)
	if err != nil {
		return nil, fmt.Errorf("evaluating element: %w", err)
	}

	return res, nil
}

// EvaluateHandle will evaluate provided page function within an execution context.
func (h *BaseJSHandle) EvaluateHandle(pageFunc string, args ...any) (JSHandleAPI, error) {
	args = append([]any{h}, args...)
	eh, err := h.execCtx.EvalHandle(h.ctx, pageFunc, args...)
	if err != nil {
		return nil, fmt.Errorf("evaluating handle for element: %w", err)
	}

	return eh, nil
}

// GetProperties retreives the JS handle's properties.
func (h *BaseJSHandle) GetProperties() (map[string]JSHandleAPI, error) {
	handles, err := h.getProperties()
	if err != nil {
		return nil, err
	}

	jsHandles := make(map[string]JSHandleAPI, len(handles))
	for k, v := range handles {
		jsHandles[k] = v
	}

	return jsHandles, nil

View on GitHub (pinned to 01ffac6f24)