*: add test case for #456
*: add test case for #456

XuHuaiyu/tidb,kyle-wang/tidb,wusphinx/tidb,8cbx/tidb,zimulala/tidb,Cofyc/tidb,anywhy/tidb,wusphinx/tidb,kyle-wang/tidb,silentred/tidb,pingcap/tidb,andelf/tidb,spongedu/tidb,ming-relax/tidb,spongedu/tidb,gaocegege/tidb,yuanwhy/tidb,ngaut/tidb,silenceper/tidb,coocood/tidb,c4pt0r/tidb,c4pt0r/tidb,Nify/tidb,louishust/tidb,pingcap/tidb,zimulala/tidb,andelf/tidb,tiancaiamao/tidb,pingcap/tidb,tiancaiamao/tidb,pingcap/tidb,Nify/tidb,astaxie/tidb,ngaut/tidb,ueizhou/tidb,ngaut/tidb,gaocegege/tidb,coocood/tidb,kyle-wang/tidb,JinheLin/tidb,zs634134578/tidb,8cbx/tidb,c4pt0r/tidb,yuanwhy/tidb,kyle-wang/tidb,CodeRushing/tidb,cosmtrek/tidb,pingcap/tidb,qiuyesuifeng/tidb,c4pt0r/tidb,pingcap/tidb,ngaut/tidb,ngaut/tidb,astaxie/tidb,kyle-wang/tidb,qhsong/tidb,XuHuaiyu/tidb,EvilMcJerkface/tidb,ngaut/tidb,kyle-wang/tidb,cosmtrek/tidb,liyu4/tidb,anywhy/tidb,myrice/tidb,JinheLin/tidb,mccxj/tidb,liyu4/tidb,ming-relax/tidb,zs634134578/tidb,yangwenmai/tidb,silenceper/tidb,myrice/tidb,qhsong/tidb,mccxj/tidb,yangwenmai/tidb,CodeRushing/tidb,c4pt0r/tidb,ueizhou/tidb,EvilMcJerkface/tidb,simon-xia/tidb,louishust/tidb,c4pt0r/tidb,silentred/tidb,Cofyc/tidb,simon-xia/tidb,qiuyesuifeng/tidb