如何把异步线程转化成同步线程进行单元测试

可以使用dispatch_group

dispatch_group_t serviceGroup = dispatch_group_create();
dispatch_group_enter(serviceGroup);
[configService startWithCompletion:^(ConfigResponse *results, NSError* error){
    // Do something with the error or results
    dispatch_group_leave(serviceGroup);
}];

dispatch_group_wait(serviceGroup,DISPATCH_TIME_FOREVER);
//需要执行的代码，检测数据