测试future方法的异步执行
public with sharing class FutureSample {
    //future在自己线程中运行，直到资源可用才运行
    @future
    public static void futuremethod(List<String> ids){
        String sql = ‘select Id,Name from Merchandise__c where Name in : ids‘;
        List<Merchandise__c> accounts = Database.query(sql);
        for(Merchandise__c account : accounts){
            System.debug(account.Id);
        }
    }
}

@isTest
private class Test_FutureSample {
    //future方法的执行必须在startTest和stopTest之间
    static testMethod void myUnitTest(){
        Test.startTest();
        List<String> ids = new String[]{‘DeskTop‘,‘Keyboard‘};
        FutureSample.futuremethod(ids);
        Test.stopTest();
    }
}