Tidy up

horizon-spec.cabal

@@ -35,15 +35,8 @@ library
   ghc-options: -Weverything -Wno-all-missed-specialisations -Wno-implicit-prelude -Wno-missing-safe-haskell-mode -Wno-prepositive-qualified-module -Wno-safe -Wno-unsafe
   build-depends:
       base >=4.7 && <5
-    , Cabal-syntax
-    , cabal2nix
-    , containers
     , dhall
-    , directory
-    , language-nix
-    , lens
     , path
     , path-dhall-instance
-    , pretty
     , text
   default-language: Haskell2010

src/Horizon/Spec.hs

 {-# LANGUAGE DeriveAnyClass    #-}
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TemplateHaskell   #-}
-
 module Horizon.Spec where
 
-import           Cabal2nix                                      (Options (..),
-                                                                 cabal2nix')
-import           Control.Lens                                   ((#))
-import           Control.Monad                                  (forM_, unless,
-                                                                 (>=>))
-import           Data.Kind                                      (Type)
-import           Data.Map                                       (Map, keys,
-                                                                 toList)
-import           Data.Text                                      (Text)
-import qualified Data.Text                                      as T
-import           Dhall                                          (FromDhall,
-                                                                 Generic,
-                                                                 ToDhall, auto,
-                                                                 input)
-import           Distribution.Compiler                          (buildCompilerId)
-import           Distribution.Nixpkgs.Fetch                     (FetchSubmodules (FetchSubmodules))
-import           Distribution.Nixpkgs.Haskell.Derivation        (Derivation)
-import           Distribution.Nixpkgs.Haskell.PackageSourceSpec (HpackUse (NoHpack))
-import           Distribution.System                            (buildPlatform)
-import           Language.Nix.Binding                           (binding)
-import           Language.Nix.Identifier                        (ident)
-import           Language.Nix.Path                              (path)
-import           Path                                           (Dir, File,
-                                                                 Path, Rel,
-                                                                 mkRelDir,
-                                                                 mkRelFile,
-                                                                 parseRelFile,
-                                                                 toFilePath,
-                                                                 (</>))
-import           Path.Dhall                                     ()
-import           System.Directory                               (createDirectoryIfMissing,
-                                                                 doesFileExist)
-import           System.IO                                      (IOMode (WriteMode),
-                                                                 hPutStrLn,
-                                                                 withFile)
-import           Text.PrettyPrint.HughesPJClass                 (prettyShow,
-                                                                 render)
+import Data.Kind  (Type)
+import Data.Text  (Text)
+import Dhall      (FromDhall, Generic, ToDhall)
+import Path       (Dir, Path, Rel)
+import Path.Dhall ()
 
 
 type Url :: Type
@@ -105,5 +70,3 @@ newtype Revision where
   MkRevision :: { fromRevision :: Text } -> Revision
   deriving stock (Show, Eq, Generic)
   deriving newtype (FromDhall, ToDhall)
-
-