module NicetiesSpec (spec) where

import Bruijn (toDeBruijn)
import Niceties (findKnown, replaceKnowns)
import Parser (Expr (Abstraction, Application, Variable))
import Test.Hspec

spec :: Spec
spec = do
  describe "can find knowns" $ do
    it "can find identity" $
      findKnown identity `shouldBe` Just "I"
  describe "replaceKnowns" $ do
    it "can replace identity" $
      replaceKnowns identity `shouldBe` Variable "I"
    it "can replace identity of identity" $
      replaceKnowns (Application identity identity) `shouldBe` Application (Variable "I") (Variable "I")
  where
    identity = toDeBruijn $ Abstraction "x" (Variable "x")