in src/ReplaceTransition.js [26:38]
handleLifecycle(handler, idx, originalArgs) {
const { children } = this.props;
const child = React.Children.toArray(children)[idx];
if (child.props[handler]) child.props[handler](...originalArgs);
if (this.props[handler]) {
const maybeNode = child.props.nodeRef
? undefined
: ReactDOM.findDOMNode(this);
this.props[handler](maybeNode);
}
}