code: func ValidateConfigMapUpdate(newCfg, oldCfg *core.ConfigMap) field.ErrorList {
  	allErrs := field.ErrorList{}
  	allErrs = append(allErrs, ValidateObjectMetaUpdate(&newCfg.ObjectMeta, &oldCfg.ObjectMeta, field.NewPath("metadata"))...)
  	allErrs = append(allErrs, ValidateConfigMap(newCfg)...)
  
  	return allErrs
  }
docs: // ValidateConfigMapUpdate tests if required fields in the ConfigMap are set.