Arbitrary (Dhall.Set.Set a): Add a shrink method

dhall-lang · Jul 15, 2019 · 2628ee6 · 2628ee6
1 parent ae9ad7d
commit 2628ee6
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/dhall/tests/Dhall/Test/QuickCheck.hs b/dhall/tests/Dhall/Test/QuickCheck.hs
@@ -61,6 +61,7 @@ instance Eq DeserialiseFailureWithEq where
 
 instance (Arbitrary a, Ord a) => Arbitrary (Set a) where
   arbitrary = Dhall.Set.fromList <$> arbitrary
+  shrink = map Dhall.Set.fromList . shrink . Dhall.Set.toList
 
 lift0 :: a -> Gen a
 lift0 = pure