Function isNode

dash/deps/prop-types@15.8.1.js:647–692

(propValue)

  }

  function isNode(propValue) {
    switch (typeof propValue) {
      case 'number':
      case 'string':
      case 'undefined':
        return true;
      case 'boolean':
        return !propValue;
      case 'object':
        if (Array.isArray(propValue)) {
          return propValue.every(isNode);
        }
        if (propValue === null || isValidElement(propValue)) {
          return true;
        }

        var iteratorFn = getIteratorFn(propValue);
        if (iteratorFn) {
          var iterator = iteratorFn.call(propValue);
          var step;
          if (iteratorFn !== propValue.entries) {
            while (!(step = iterator.next()).done) {
              if (!isNode(step.value)) {
                return false;
              }
            }
          } else {
            // Iterator will provide entry [k,v] tuples rather than values.
            while (!(step = iterator.next()).done) {
              var entry = step.value;
              if (entry) {
                if (!isNode(entry[1])) {
                  return false;
                }
              }
            }
          }
        } else {
          return false;
        }

        return true;
      default:
        return false;
    }
  }

  function isSymbol(propType, propValue) {
    // Native Symbol.