swift - Comparing array of force unwrapped optionals -

i'm writing test:

    func test_arrayfromshufflingarray() {          var videos = [mockobjects.mockvmvideo_1(), mockobjects.mockvmvideo_2(), mockobjects.mockvmvideo_3()]         let tuple = shufflehelper.arrayfromshufflingarray(videos, currentindex:1)          var shuffledvideos = tuple.0         let shuffleindexmap = tuple.1           // -- test order different         xctassert(videos != shuffledvideos, "test_arrayfromshufflingarray fail")     } 

but on last line last line:

binary operator '!=' cannot applied 2 '[vmvideo!]' operands 

arrays can compared == if element type equatable:

/// returns true if these arrays contain same elements. public func ==<element : equatable>(lhs: [element], rhs: [element]) -> bool 

but neither implicitlyunwrappedoptional<wrapped> nor optional<wrapped> conform equatable, if underlying type wrapped does.

possible options (assuming vmvideo conforms equatable):

• change code videos , shuffledvideos [vmvideo] arrays instead of [vmvideo!].

• compare arrays elementwise:

  xctassert(videos.count == shuffledvideos.count     && !zip(videos, shuffledvideos).contains {$0 != $1 }) 

• define == operator arrays of implicitly unwrapped equatable elements:

  func ==<element : equatable> (lhs: [element!], rhs: [element!]) -> bool {     return lhs.count == rhs.count && !zip(lhs, rhs).contains {$0 != $1 } }