in core/index.js [78:86]
function generateTaskByBuildTaskTree(taskTree) {
const executionModel = Array.isArray(taskTree) ? "series" : taskTree.executionModel;
const targetTasks = Array.isArray(taskTree) ? taskTree : taskTree.tasks;
const createTaskFn = executionModel === "parallel" ? gulp.parallel : gulp.series;
return createTaskFn(targetTasks
.filter((task) => !utils.isNullOrUndefined(task))
.map((task) => utils.isString(task) ? task : generateTaskByBuildTaskTree(task)));
}