Add some Pretty instances

and golden tests

test/Main.hs

@@ -0,0 +1,55 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE ExistentialQuantification #-}
+module Main (main) where
+
+import Language.QBE
+
+import Test.Tasty (TestTree, defaultMain, testGroup)
+import Test.Tasty.Silver (goldenVsAction)
+import System.FilePath ((</>), (<.>))
+import Prettyprinter (Pretty(pretty), layoutPretty, defaultLayoutOptions)
+import Prettyprinter.Render.Text (renderStrict)
+
+
+data P = forall a. Pretty a => P a
+instance Pretty P where
+  pretty (P x) = pretty x
+
+main :: IO ()
+main = defaultMain goldenTests
+
+goldenTests :: TestTree
+goldenTests = testGroup "golden tests"
+  [ t "ident"
+      [ P $ Ident @'AggregateTy "aggregateTy"
+      , P $ Ident @'Global "global"
+      , P $ Ident @'Temporary "temporary"
+      , P $ Ident @'Label "label"
+      ]
+  , t "type" ([Word, Long, Single, Double], [BaseTy Word, Byte, HalfWord])
+  , t "const"
+      [ CInt True 1
+      , CInt False 2
+      , CSingle 0.1
+      , CDouble (-0.2)
+      , CGlobal $ Ident "global"
+      ]
+  , t "linkage" (Export, Section "secName" Nothing, Section "secName" $ Just "flag1 flag2")
+  , t "typedef" $ Typedef (Ident "t") (Just 8)
+      [ (SubExtTy HalfWord, Just 16)
+      , (SubAggregateTy (Ident "t1"), Nothing)
+      ]
+  , t "opaque" $ Opaque (Ident "t") 8 16
+  , t "val" [ValConst (CInt False 0), ValTemporary $ Ident "temporary", ValGlobal $ Ident "global"]
+  , t "jmp" $ Jmp $ Ident "target"
+  , t "jnz" $ Jnz (ValConst $ CInt False 0) (Ident "target1") (Ident "target2")
+  , t "ret" $ Ret $ Just $ ValTemporary $ Ident "x"
+  ]
+  where
+    t name value = goldenVsAction
+      name
+      ("golden" </> name <.> "qbe")
+      (pure $ pretty value)
+      (renderStrict . layoutPretty defaultLayoutOptions)