update: implement sized elements

Author: cstml

lambda-buffers-compiler/lambda-buffers-compiler.cabal

@@ -37,6 +37,7 @@ common common-language
     DeriveLift
     DeriveTraversable
     DerivingStrategies
+    DerivingVia
     DoAndIfThenElse
     DuplicateRecordFields
     EmptyCase
@@ -94,6 +95,7 @@ library
   build-depends:
     , containers                  >=0.6.5.1
     , freer-simple                >=1.2
+    , generic-arbitrary
     , generic-lens                >=2.2
     , lambda-buffers-compiler-pb  >=0.1.0.0
     , mtl                         >=2.2
@@ -116,6 +118,7 @@ library
     LambdaBuffers.Compiler.ProtoCompat
     LambdaBuffers.Compiler.ProtoCompat.Types
     LambdaBuffers.Compiler.TypeClassCheck
+    Orphan.Text
 
   hs-source-dirs:  src
 
@@ -145,8 +148,10 @@ test-suite tests
     , lambda-buffers-compiler
     , lambda-buffers-compiler-pb  >=0.1
     , proto-lens                  >=0.7
+    , QuickCheck                  >=2.14
     , tasty                       >=1.4
     , tasty-hunit                 >=0.10
+    , tasty-quickcheck            >=0.10
     , text                        >=1.2
 
   other-modules:

lambda-buffers-compiler/src/LambdaBuffers/Compiler/KindCheck/Type.hs

@@ -2,6 +2,7 @@ module LambdaBuffers.Compiler.KindCheck.Type (Type (Var, Abs, App)) where
 
 import LambdaBuffers.Compiler.KindCheck.Variable (Var)
 import Prettyprinter (Doc, Pretty (pretty), parens, (<+>))
+import Test.QuickCheck (Arbitrary, arbitrary, oneof, sized)
 
 data Type
   = Var Var
@@ -20,3 +21,15 @@ instance Pretty Type where
         Var a -> pretty a
         App t1 t2 -> parens $ show' t1 <+> show' t2
         Abs a t1 -> parens $ "λ" <> pretty a <> "." <> show' t1
+
+instance Arbitrary Type where
+  arbitrary = sized f
+    where
+      f n
+        | n <= 0 = Var <$> arbitrary
+        | otherwise =
+            oneof
+              [ Var <$> arbitrary
+              , App <$> f (n `div` 2) <*> f (n `div` 2)
+              , Abs <$> arbitrary <*> f (n - 1)
+              ]

lambda-buffers-compiler/src/LambdaBuffers/Compiler/KindCheck/Variable.hs

@@ -1,6 +1,7 @@
 module LambdaBuffers.Compiler.KindCheck.Variable (Atom, Var) where
 
 import Data.Text (Text)
+import Orphan.Text
 
 type Atom = Text
 type Var = Text