Karnataka's ruling coalition, on the edge after a series of resignations, will take a floor test on Thursday, a senior Congress leader said today. The floor test will take place at 11 am on July 18, said Congress's Siddaramaiah after a meeting of a panel that decides the agenda of the state assembly. The Congress-Janata Dal Secular coalition, which has been wobbly since it came to power last May, was jolted by 18 resignations over the past two weeks.