in gulpfile.js [53:60]
function runNpmTasks(taskName, dirs) {
for (var i = 0; i < dirs.length; i++) {
var rc = runNpmTask(taskName, dirs[i]);
if (rc !== 0) {
throw new Error(`$Error: command \`${taskName}\` in directory ${dirs[i]} failed with return code ${rc}`);
}
}
}