英语语法分析

When a doh.Deferred object is returned from a unit test, you must catch all errors from the asynch call and pass them to the object's errback method.

当从单元测试中返回一个 doh.Deferred 对象时，必须捕获异步调用中产生的所有错误信息并把它们传递给对象的 errback 方法。