Bluffalo allows you to do real mocking and stubbing in Swift.

What does it do?

It generates a fake subclass, from a Swift class or protocol, and allows you to stub and inspect which methods were called on the fake.

Limitations

Because this relies on subclassing, this will not work for stubs.
Properties cannot be stubbed yet.

Installing

$ brew install https://raw.githubusercontent.com/Nordstrom/bluffalo/master/Bluffalo.rb

Usage

Generating a fake

bluffalo -f path/to/Cat.swift -o path/to/FakeCat.swift -m MyContainingModule

Using a fake

Let's say we have the following class:

class Cat {
  func numberOfLives() -> Int {
    return 9
  }

  func meow(numberOfTimes: Int) {
    while i < numberOfTimes {
      print("Meow")
    }
  }
}

Stubbing Values

let fakeCat = FakeCat()
print( fakeCat.numberOfLives() ) // prints 9
fakeCat.stub(.numberOfLives()).andReturn(4)
print( fakeCat.numberOfLives() ) // prints 4

Mocking

let fakeCat = FakeCat()
let numberOfLives = fakeCat.numberOfLives()
fakeCat.meow(numberOfTimes: 5)

print( fakeCat.didCall(method: .numberOfLives()) ) // prints true
print( fakeCat.matchingMethods(.numberOfLives()) ) // prints 1

// Arguments matter
print( fakeCat.didCall(method: .meow(numberOfTimes: 5)) ) // prints true
print( fakeCat.didCall(method: .meow(numberOfTimes: 4)) ) // prints false

blladnar/bluffalo