enzyme/_book/gitbook/plugins/gitbook-plugin-collapsible-menu/plugin.js

JavaScript Testing utilities for React

require(["gitbook"], function(gitbook) {
    gitbook.events.bind("page.change", function() {
        $('ul.summary li li').hide();
        // $('ul.summary li').find('li.active').parent().children().show();
        $('ul.summary li li.active').parents().children().show();
        $('ul.summary li.active > ul > li').show();        
    });
});