Revert "Make quickcheck-classes usage optional (again)"

This reverts commit 22fdeeb.

tests/Properties/Stack.hs

@@ -1,9 +1,5 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE ScopedTypeVariables #-}
-
-#ifdef VERSION_quickcheck_classes
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
-#endif
 
 module Properties.Stack where
 
@@ -15,13 +11,11 @@ import qualified XMonad.StackSet as S (filter)
 
 import Data.Maybe
 
-#ifdef VERSION_quickcheck_classes
 import Data.Proxy
 import Test.QuickCheck.Classes (
     Laws (lawsTypeclass, lawsProperties), Proxy1 (Proxy1),
     foldableLaws, traversableLaws,
     )
-#endif
 
 
 -- The list returned by index should be the same length as the actual
@@ -65,7 +59,6 @@ prop_differentiate xs =
     where _ = xs :: [Int]
 
 
-#ifdef VERSION_quickcheck_classes
 -- Check type class laws of 'Data.Foldable.Foldable' and 'Data.Traversable.Traversable'.
 newtype TestStack a = TestStack (Stack a)
     deriving (Eq, Read, Show, Foldable, Functor)
@@ -82,6 +75,3 @@ prop_laws_Stack = format (foldableLaws p) <> format (traversableLaws p)
     p = Proxy :: Proxy TestStack
     format laws = [ ("Stack: " <> lawsTypeclass laws <> ": " <> name, prop)
                   | (name, prop) <- lawsProperties laws ]
-#else
-prop_laws_Stack = []
-#endif

xmonad.cabal

@@ -54,8 +54,6 @@ flag pedantic
   default:     False
   manual:      True
 
-flag quickcheck-classes
-
 library
   exposed-modules: XMonad
                    XMonad.Config
@@ -125,15 +123,12 @@ test-suite properties
   hs-source-dirs: tests
   build-depends:  base
                 , QuickCheck >= 2
+                , quickcheck-classes >= 0.4.3
                 , X11
                 , containers
                 , xmonad
   default-language: Haskell2010
 
-  if flag(quickcheck-classes)
-    -- quickcheck-classes or its deps conflict with template-haskell in GHC 9.10 as of 2024-05-13
-    build-depends: quickcheck-classes >= 0.4.3
-
   if impl(ghc > 9.8)
     ghc-options:   -Wno-x-partial