type fakeController … func (f *fakeController) Run(ctx context.Context) { … } func createLegacyIPAM( ctx context.Context, ic *Controller, nodeInformer coreinformers.NodeInformer, cloud cloudprovider.Interface, kubeClient clientset.Interface, clusterCIDRs []*net.IPNet, serviceCIDR *net.IPNet, nodeCIDRMaskSizes []int, ) (*fakeController, error) { … }