add ut in show_test (#10083)
add ut in show_test (#10083)


ming-relax/tidb,ngaut/tidb,qiuyesuifeng/tidb,ming-relax/tidb,EvilMcJerkface/tidb,cosmtrek/tidb,kyle-wang/tidb,Cofyc/tidb,c4pt0r/tidb,kyle-wang/tidb,ngaut/tidb,pingcap/tidb,kyle-wang/tidb,kyle-wang/tidb,c4pt0r/tidb,cosmtrek/tidb,c4pt0r/tidb,c4pt0r/tidb,pingcap/tidb,coocood/tidb,c4pt0r/tidb,coocood/tidb,pingcap/tidb,pingcap/tidb,ngaut/tidb,kyle-wang/tidb,c4pt0r/tidb,Cofyc/tidb,EvilMcJerkface/tidb,qiuyesuifeng/tidb,kyle-wang/tidb,ngaut/tidb,pingcap/tidb,XuHuaiyu/tidb,ngaut/tidb,pingcap/tidb,ngaut/tidb,XuHuaiyu/tidb