1
0
Files

34 lines
1.2 KiB
Haskell

module Main where
import Test.Hspec
import Data.Queue
main :: IO ()
main = hspec $ do
describe "empty" $ do
it "returns an empty queue" $ do
(empty :: Queue Int) `shouldBe` (Queue [] [])
describe "push" $ do
it "puts an element into an empty queue" $ do
(push 5 empty) `shouldBe` (Queue [5] [])
describe "pop" $ do
it "takes the only element from the queue" $ do
(pop (Queue [5] [])) `shouldBe` (Just (5, Queue [] []))
it "returns nothing if the queue is empty" $ do
(pop ((Queue [] [])::Queue Int)) `shouldBe` Nothing
it "takes elements in the FIFO order" $ do
let queue = push 3 (push 5 empty)
in pop queue `shouldBe` Just (5, Queue [] [3])
describe "isEmpty" $ do
it "tells when the queue is empty" $ do
(isEmpty (empty :: Queue Int)) `shouldBe` True
it "tells when the enqueue part isn't empty" $ do
let queue = push 3 empty
in isEmpty queue `shouldBe` False
it "tells when the dequeue part isn't empty" $ do
let queue = fmap snd (pop $ push 3 (push 5 empty))
in fmap isEmpty queue `shouldBe` Just False