Function traverseAllChildrenImpl

examples/simple/react.js:17054–17128

* @param {?*} children Children tree container. * @param {!string} nameSoFar Name of the key path so far. * @param {!function} callback Callback to invoke with each child found. * @param {?*} traverseContext Used to pass information throughout the traversal * process. * @return {!number} The nu

(children, nameSoFar, callback, traverseContext)

 * @return {!number} The number of children in this subtree.
 */
function traverseAllChildrenImpl(children, nameSoFar, callback, traverseContext) {
  var type = typeof children;

  if (type === 'undefined' || type === 'boolean') {
    // All of the above are perceived as null.
    children = null;
  }

  if (children === null || type === 'string' || type === 'number' || ReactElement.isValidElement(children)) {
    callback(traverseContext, children,
    // If it's the only child, treat the name as if it was wrapped in an array
    // so that it's consistent if the number of children grows.
    nameSoFar === '' ? SEPARATOR + getComponentKey(children, 0) : nameSoFar);
    return 1;
  }

  var child;
  var nextName;
  var subtreeCount = 0; // Count of children found in the current subtree.
  var nextNamePrefix = nameSoFar === '' ? SEPARATOR : nameSoFar + SUBSEPARATOR;

  if (Array.isArray(children)) {
    for (var i = 0; i < children.length; i++) {
      child = children[i];
      nextName = nextNamePrefix + getComponentKey(child, i);
      subtreeCount += traverseAllChildrenImpl(child, nextName, callback, traverseContext);
    }
  } else {
    var iteratorFn = getIteratorFn(children);
    if (iteratorFn) {
      var iterator = iteratorFn.call(children);
      var step;
      if (iteratorFn !== children.entries) {
        var ii = 0;
        while (!(step = iterator.next()).done) {
          child = step.value;
          nextName = nextNamePrefix + getComponentKey(child, ii++);
          subtreeCount += traverseAllChildrenImpl(child, nextName, callback, traverseContext);
        }
      } else {
        if ("development" !== 'production') {
          "development" !== 'production' ? warning(didWarnAboutMaps, 'Using Maps as children is not yet fully supported. It is an ' + 'experimental feature that might be removed. Convert it to a ' + 'sequence / iterable of keyed ReactElements instead.') : undefined;
          didWarnAboutMaps = true;
        }
        // Iterator will provide entry [k,v] tuples rather than values.
        while (!(step = iterator.next()).done) {
          var entry = step.value;
          if (entry) {
            child = entry[1];
            nextName = nextNamePrefix + wrapUserProvidedKey(entry[0]) + SUBSEPARATOR + getComponentKey(child, 0);
            subtreeCount += traverseAllChildrenImpl(child, nextName, callback, traverseContext);
          }
        }
      }
    } else if (type === 'object') {
      var addendum = '';
      if ("development" !== 'production') {
        addendum = ' If you meant to render a collection of children, use an array ' + 'instead or wrap the object using createFragment(object) from the ' + 'React add-ons.';