Bug in Queue.deQueue()

[JenkinsJB]

I think there is a bug in the implementation of Queue.deQueue() . Consider the following code:

var w = Queue<Int>()
println(w.count) // prints "0" as expected
w.enQueue(1)
println(w.count) // prints "1" - as expected
w.deQueue()
println(w.count) // should print "0", but instead, you get a fatal error

In xCode 6.3.1, this code in a playground gives the following fatal error: fatal error: unexpectedly found nil while unwrapping an Optional value Playground execution failed: Execution was interrupted, reason: EXC_BAD_INSTRUCTION

This is due to the fact that deQueue() at line 102 sets top to nil when there is no next item in the queue. count then blows up when it tries to access top.key which is an implicitly unwrapped optional. A fix would be to instead set top to QNode<T>() on 102.

[JenkinsJB]

Pull request with fix created.

Jason

[JenkinsJB]

Created new PR against develop branch per tweet from @waynewbishop

[waynewbishop]

Hi Jason;

Thanks again for fixing this issue. Your changes have been merged into the main branch along with some new unit tests!