Fix bug in Property.recheck where the result is always Failed #408

Author: TysonMN

CHANGELOG.md

@@ -1,3 +1,7 @@
+## Version TBD
+
+- Fix bug in `Property.recheck` where the result is always `Failed`. ([#415][415], [@TysonMN][TysonMN])
+
 ## Version 0.12.1 (2021-12-31)
 
 - Add `Tree.apply`. Change `Gen.apply` from monadic to applicative. Revert runtime optimization of `Gen.integral`. ([#398][398], [@TysonMN][TysonMN])
@@ -192,6 +196,8 @@
 [porges]:
   https://github.com/porges
 
+[415]:
+  https://github.com/hedgehogqa/fsharp-hedgehog/pull/415
 [401]:
   https://github.com/hedgehogqa/fsharp-hedgehog/pull/401
 [400]:

src/Hedgehog/Property.fs

@@ -163,11 +163,15 @@ module Property =
         let rec skipPassedChild children shrinkPath =
             match children, shrinkPath with
             | _, [] ->
-                Failed {
-                    Shrinks = 0<shrinks>
-                    Journal = root.Value |> fst
-                    RecheckInfo = None
-                }
+                let journal, outcome = root.Value
+                match outcome with
+                | Failure ->
+                    { Shrinks = 0<shrinks>
+                      Journal = journal
+                      RecheckInfo = None }
+                    |> Failed
+                | Success _ -> OK
+                | Discard -> failwith "Unexpected 'Discard' result when rechecking. This should never happen."
             | [], _ -> failwith "The shrink path lead to a dead end. This should never happen."
             | _ :: childrenTail, ShrinkOutcome.Pass :: shrinkPathTail -> skipPassedChild  childrenTail shrinkPathTail
             | childrenHead :: _, ShrinkOutcome.Fail :: shrinkPathTail -> followShrinkPath childrenHead shrinkPathTail