Move the Arbitrary instance for Patch into semantic-diff proper.

bench/Main.hs

@@ -13,6 +13,7 @@ import Data.Text.Arbitrary ()
 import Data.These
 import Diff
 import Patch
+import Patch.Arbitrary ()
 import Prologue
 import Syntax
 import Term.Arbitrary
@@ -79,11 +80,3 @@ instance (Eq leaf, Eq annotation, Arbitrary leaf, Arbitrary annotation) => Arbit
         Fixed f -> Fixed <$> (List.subsequences f >>= recursivelyShrink)
         Keyed k -> Keyed . Map.fromList <$> (List.subsequences (Map.toList k) >>= recursivelyShrink)
     Pure patch -> ArbitraryDiff . Pure <$> shrink patch
-
-instance Arbitrary a => Arbitrary (Patch a) where
-  arbitrary = oneof [
-    Insert <$> arbitrary,
-    Delete <$> arbitrary,
-    Replace <$> arbitrary <*> arbitrary ]
-
-  shrink patch = traverse shrink patch

semantic-diff.cabal

@@ -27,6 +27,7 @@ library
                      , Operation
                      , Parser
                      , Patch
+                     , Patch.Arbitrary
                      , Range
                      , Renderer
                      , Renderer.JSON

src/Patch/Arbitrary.hs

@@ -0,0 +1,14 @@
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+module Patch.Arbitrary where
+
+import Patch
+import Prologue
+import Test.QuickCheck
+
+instance Arbitrary a => Arbitrary (Patch a) where
+  arbitrary = oneof [
+    Insert <$> arbitrary,
+    Delete <$> arbitrary,
+    Replace <$> arbitrary <*> arbitrary ]
+
+  shrink patch = traverse shrink patch

test/ArbitraryTerm.hs

@@ -7,7 +7,6 @@ import Data.Functor.Both
 import Data.Text.Arbitrary ()
 import Data.These
 import Info
-import Patch
 import Prologue hiding (fst, snd)
 import Range
 import Source hiding ((++))
@@ -33,12 +32,6 @@ instance Arbitrary a => Arbitrary (Join These a) where
   arbitrary = Join <$> arbitrary
   shrink (Join a) = Join <$> shrink a
 
-instance Arbitrary a => Arbitrary (Patch a) where
-  arbitrary = oneof [
-    Insert <$> arbitrary,
-    Delete <$> arbitrary,
-    Replace <$> arbitrary <*> arbitrary ]
-
 instance Arbitrary a => Arbitrary (Source a) where
   arbitrary = Source.fromList <$> arbitrary