Xcode 7 beta 3 + Swift

DemoTesting01Tests.swift

import XCTest
@testable import DemoTesting01

class DemoTesting01Tests: XCTestCase {

}

DemoTesting01Tests02.swift

import XCTest
@testable import DemoTesting01

class DemoTesting01Tests: XCTestCase {
    
    let fizzBuzz = FizzBuzz()
    
    func testOne() {
        XCTAssertEqual("1", fizzBuzz.say(1))
    }
    
    func testFizz() {
        XCTAssertEqual("Fizz", fizzBuzz.say(3))
    }
    
}

FizzBuzz.swift

class FizzBuzz {
    func say(number: Int) -> String {
        if(number%3 == 0) {
            return "Fizz"
        }
        if(number == 2) {
            return "2"
        }
        return "1"
    }
}