var gulp = require('gulp');
var fs = require('fs');
var path = require('path');

// 注册
var deep = 3;
run_tasks('_tasks');

function run_tasks(tasks_path) {
  if (--deep < 0) {
    throw new Error('something wrong in require tasks!');
    // eslint-disable-next-line no-unreachable
    return;
  }

  tasks_path = path.join('../', tasks_path);

  if (fs.existsSync(tasks_path)) {
    require(tasks_path)(gulp);
  } else {
    run_tasks(tasks_path);
  }
}