Function getComponentKey

docs/lib/react.js:17572–17581

* Generate a key string that identifies a component within a set. * * @param {*} component A component that could contain a manual key. * @param {number} index Index that is used if a manual key is not provided. * @return {string}

(component, index)

 * @return {string}
 */
function getComponentKey(component, index) {
  // Do some typechecking here since we call this blindly. We want to ensure
  // that we don't block potential future ES APIs.
  if (component && typeof component === 'object' && component.key != null) {
    // Explicit key
    return wrapUserProvidedKey(component.key);
  }
  // Implicit key determined by the index in the set
  return index.toString(36);
}

/**
 * Escape a component key so that it is safe to use in a reactid.