var nodePath = require('path'); exports.check = function(marko, markoCompiler, expect, done) { var template = marko.load(nodePath.join(__dirname, 'template.marko')); var output; var e; try { output = template.renderSync({ nameDataProvider: function(arg, callback) { setTimeout(function() { callback(null, 'John'); }, 100); } }); } catch(_e) { e = _e; } expect(output).to.equal(undefined); expect(e).to.not.equal(undefined); done(); };