Xcode lost button test in xctest

I working on Xcode 6. When I coding XCTest, Xcode has been crash. When I reopen my Xcode, and it lost little diamond run button.

It should be:

http://ift.tt/1HTj9Ic

But it got:

http://ift.tt/1DLkrHM

Thank a lot, sorry for my bad english.