fib.swift

import Foundation

extension Int {
    func timesMap(closure: (Int) -> AnyObject) -> Array<AnyObject> {
        var array: AnyObject[] = []
        for x in 1...self {
            array += closure(x)
        }
        return array;
    }
}

class Fib {
    class func at(num: Int) -> Int {
        switch num {
            case 0, 1, 2:
                return 1
            default:
                return at(num-2) + at(num-1)
        }
    }
    
    class func sequence(num: Int) -> Array<AnyObject> {
        return num.timesMap({ x -> AnyObject in return Fib.at(x) })
    }
}

fib_test.swift

import XCTest

class SwiftPlaygroundTests: XCTestCase {
    
    func testFibSequence() {
        XCTAssertEqualObjects(Fib.at(7), 13)
        XCTAssertEqualObjects(Fib.sequence(7), [1, 1, 2, 3, 5, 8, 13])
    }

}