testem-client-hook.js
Testem.afterTests(function(config, data, callback) {
console.log("sending coverage results from client...");
var coverage = JSON.stringify(window.__coverage__);
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (xhr.readyState === 4) {
callback();
}
};
xhr.open("POST", "/coverage", true);
xhr.send(coverage);
});