Polysemy Mocks

Overview

polysemy-mocks aims to provide a structure to write all mocks for polysemy and to generate those.

Example

{-# LANGUAGE DataKinds #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE FlexibleInstances #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE LambdaCase #-} {-# LANGUAGE MultiParamTypeClasses #-} {-# LANGUAGE RankNTypes #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE TypeApplications #-} {-# LANGUAGE TypeFamilies #-} {-# LANGUAGE TypeOperators #-} module TeletypeSpec where import Data.Kind import Polysemy import Polysemy.Internal (send) import Test.Hspec import Test.Polysemy.Mock import Test.Polysemy.Mock.TH (genMock) import Prelude hiding (read) data Teletype (m :: Type -> Type) a where Read :: Teletype m String Write :: String -> Teletype m () makeSem ''Teletype genMock ''Teletype program :: Member Teletype r => Sem r () program = do write "Name: " name <- read write $ "Hello " <> name spec :: Spec spec = describe "program" $ do it "greets" $ runM @IO . evalMock $ do mockReadReturns (pure "Akshay") mock @Teletype @IO program writes <- mockWriteCalls embed $ writes `shouldBe` ["Name: ", "Hello Akshay"]