+Test of traversal overload

src/FSharpPlus/Control/Traversable.fs

@@ -33,87 +33,147 @@ type Traverse =
     static member inline InvokeOnInstance f (t: ^a) = (^a : (static member Traverse : _*_ -> 'R) t, f)
 
     static member inline Traverse (t: '``Traversable<'T>``  , f: 'T->'``Functor<'U>``, [<Optional>]_output: '``Functor<'Traversable<'U>>``, [<Optional>]_impl: Default4) =
-        let mapped = Map.Invoke f t : '``Traversable<'Functor<'U>>``
-        (^``Traversable<'T>`` : (static member Sequence : _ -> _) mapped) : '``Functor<'Traversable<'U>>``
-
-    static member inline Traverse (t: Id<_>, f, [<Optional>]_output: 'R, [<Optional>]_impl: Default3) = Map.Invoke Id.create (f (Id.run t))
+       #if TEST_TRACE
+       Traces.add "Traverse 'Traversable, 'T->Functor<'U>"
+       #endif
+       let mapped = Map.Invoke f t : '``Traversable<'Functor<'U>>``
+       (^``Traversable<'T>`` : (static member Sequence : _ -> _) mapped) : '``Functor<'Traversable<'U>>``
+
+    static member inline Traverse (t: Id<_>, f, [<Optional>]_output: 'R, [<Optional>]_impl: Default3) =
+       #if TEST_TRACE
+       Traces.add "Traverse Id"
+       #endif
+       Map.Invoke Id.create (f (Id.run t))
 
     static member inline Traverse (t: _ seq, f, [<Optional>]_output: 'R, [<Optional>]_impl: Default3) =
+       #if TEST_TRACE
+       Traces.add "Traverse seq"
+       #endif
        let cons x y = seq {yield x; yield! y}
        let cons_f x ys = Map.Invoke (cons: 'a->seq<_>->seq<_>) (f x) <*> ys
        Seq.foldBack cons_f t (result Seq.empty)
 
     static member inline Traverse (t: _ NonEmptySeq, f, [<Optional>]_output: 'R, [<Optional>]_impl: Default3) =
+       #if TEST_TRACE
+       Traces.add "Traverse NonEmptySeq"
+       #endif
        let cons x y = seq {yield x; yield! y}
        let cons_f x ys = Map.Invoke (cons: 'a->seq<_>->seq<_>) (f x) <*> ys
        Map.Invoke NonEmptySeq.ofSeq (Seq.foldBack cons_f t (result Seq.empty))
 
     static member inline Traverse (t: seq<'T>, f: 'T->'``Functor<'U>``, [<Optional>]_output: '``Functor<seq<'U>>``, [<Optional>]_impl: Default2) =
-        let mapped = Seq.map f t
-        Sequence.ForInfiniteSequences (mapped, IsLeftZero.Invoke, List.toSeq) : '``Functor<seq<'U>>``
+       #if TEST_TRACE
+       Traces.add "Traverse seq, 'T->Functor<'U>"
+       #endif
+       let mapped = Seq.map f t
+       Sequence.ForInfiniteSequences (mapped, IsLeftZero.Invoke, List.toSeq) : '``Functor<seq<'U>>``
 
     static member inline Traverse (t: NonEmptySeq<'T>, f: 'T->'``Functor<'U>``, [<Optional>]_output: '``Functor<NonEmptySeq<'U>>``, [<Optional>]_impl: Default2) =
-        let mapped = NonEmptySeq.map f t
-        Sequence.ForInfiniteSequences (mapped, IsLeftZero.Invoke, NonEmptySeq.ofList) : '``Functor<NonEmptySeq<'U>>``
-
-    static member inline Traverse (t: ^a   , f, [<Optional>]_output: 'R, [<Optional>]_impl: Default1) = Traverse.InvokeOnInstance f t : 'R
+       #if TEST_TRACE
+       Traces.add "Traverse NonEmptySeq, 'T->Functor<'U>"
+       #endif
+       let mapped = NonEmptySeq.map f t
+       Sequence.ForInfiniteSequences (mapped, IsLeftZero.Invoke, NonEmptySeq.ofList) : '``Functor<NonEmptySeq<'U>>``
+
+    static member inline Traverse (t: ^a   , f, [<Optional>]_output: 'R, [<Optional>]_impl: Default1) =
+       #if TEST_TRACE
+       Traces.add "Traverse ^a"
+       #endif
+       Traverse.InvokeOnInstance f t : 'R
     static member inline Traverse (_: ^a when ^a : null and ^a :struct, _, _: 'R   , _impl: Default1) = id
 
     #if !FABLE_COMPILER
     static member Traverse (t: 't seq, f: 't->Async<'u>, [<Optional>]_output: Async<seq<'u>>, [<Optional>]_impl: Traverse) : Async<seq<_>> = async {
-        let! ct = Async.CancellationToken
-        return seq {
-            use enum = t.GetEnumerator ()
-            while enum.MoveNext() do
-                yield Async.RunSynchronously (f enum.Current, cancellationToken = ct) }}
+       #if TEST_TRACE
+       Traces.add "Traverse 't seq, 't->Async<'u>"
+       #endif
+
+       let! ct = Async.CancellationToken
+       return seq {
+           use enum = t.GetEnumerator ()
+           while enum.MoveNext() do
+               yield Async.RunSynchronously (f enum.Current, cancellationToken = ct) }}
     #endif
 
     #if !FABLE_COMPILER
     static member Traverse (t: 't NonEmptySeq, f: 't->Async<'u>, [<Optional>]_output: Async<NonEmptySeq<'u>>, [<Optional>]_impl: Traverse) : Async<NonEmptySeq<_>> = async {
-        let! ct = Async.CancellationToken
-        return seq {
-            use enum = t.GetEnumerator ()
-            while enum.MoveNext() do
-                yield Async.RunSynchronously (f enum.Current, cancellationToken = ct) } |> NonEmptySeq.unsafeOfSeq }
+       #if TEST_TRACE
+       Traces.add "Traverse 't NonEmptySeq, 't->Async<'u>"
+       #endif
+
+       let! ct = Async.CancellationToken
+       return seq {
+           use enum = t.GetEnumerator ()
+           while enum.MoveNext() do
+               yield Async.RunSynchronously (f enum.Current, cancellationToken = ct) } |> NonEmptySeq.unsafeOfSeq }
     #endif
 
-    static member        Traverse (t: Id<'t>   , f: 't->option<'u>, [<Optional>]_output: option<Id<'u>>, [<Optional>]_impl: Traverse) = Option.map Id.create (f (Id.run t))
-    static member inline Traverse (t: option<_>, f, [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R = match t with Some x -> Map.Invoke Some (f x) | _ -> result None
-    static member inline Traverse (t: voption<_>, f, [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R = match t with ValueSome x -> Map.Invoke ValueSome (f x) | _ -> result ValueNone
+    static member        Traverse (t: Id<'t>   , f: 't->option<'u>, [<Optional>]_output: option<Id<'u>>, [<Optional>]_impl: Traverse) =
+       #if TEST_TRACE
+       Traces.add "Traverse Id, 't->option<'u>"
+       #endif
+       Option.map Id.create (f (Id.run t))
+    static member inline Traverse (t: option<_>, f, [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R =
+       #if TEST_TRACE
+       Traces.add "Traverse option"
+       #endif
+       match t with Some x -> Map.Invoke Some (f x) | _ -> result None
+    static member inline Traverse (t: voption<_>, f, [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R =
+       #if TEST_TRACE
+       Traces.add "Traverse voption"
+       #endif
+       match t with ValueSome x -> Map.Invoke ValueSome (f x) | _ -> result ValueNone
 
     static member inline Traverse (t:Map<_,_>  , f, [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R =
-        let insert_f m k v = Map.Invoke (Map.add k) v <*> m        
-        Map.fold insert_f (result Map.empty) (Map.mapValues f t)
+       #if TEST_TRACE
+       Traces.add "Traverse Map"
+       #endif
+       let insert_f m k v = Map.Invoke (Map.add k) v <*> m        
+       Map.fold insert_f (result Map.empty) (Map.mapValues f t)
 
     static member inline Traverse (t: Result<'T,'Error>, f: 'T->'``Functor<'U>``, [<Optional>]_output: '``Functor<Result<'U,'Error>>``, [<Optional>]_impl: Traverse) : '``Functor<Result<'U,'Error>>`` =
-        match t with
-        | Ok a    -> Map.Invoke Result<'U,'Error>.Ok (f a)
-        | Error e -> Return.Invoke (Result<'U,'Error>.Error e)
+       #if TEST_TRACE
+       Traces.add "Traverse Result, 'T->Functor<'U>"
+       #endif
+       match t with
+       | Ok a    -> Map.Invoke Result<'U,'Error>.Ok (f a)
+       | Error e -> Return.Invoke (Result<'U,'Error>.Error e)
 
     static member inline Traverse (t: Choice<'T,'Error>, f: 'T->'``Functor<'U>``, [<Optional>]_output: '``Functor<Choice<'U,'Error>>``, [<Optional>]_impl: Traverse) : '``Functor<Choice<'U,'Error>>`` =
-        match t with
-        | Choice1Of2 a -> Map.Invoke Choice<'U,'Error>.Choice1Of2 (f a)
-        | Choice2Of2 e -> Return.Invoke (Choice<'U,'Error>.Choice2Of2 e)
+       #if TEST_TRACE
+       Traces.add "Traverse Choice, 'T->Functor<'U>"
+       #endif
+       match t with
+       | Choice1Of2 a -> Map.Invoke Choice<'U,'Error>.Choice1Of2 (f a)
+       | Choice2Of2 e -> Return.Invoke (Choice<'U,'Error>.Choice2Of2 e)
 
     static member inline Traverse (t:list<_>   ,f , [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R =
-        let rec loop acc = function
-            | [] -> acc
-            | x::xs -> 
-                let v = f x
-                loop (v::acc) xs
-        let cons_f x xs = Map.Invoke List.cons xs <*> x
-        List.fold cons_f (result []) (loop [] t)
+       #if TEST_TRACE
+       Traces.add "Traverse list"
+       #endif
+
+       let rec loop acc = function
+           | [] -> acc
+           | x::xs -> 
+               let v = f x
+               loop (v::acc) xs
+       let cons_f x xs = Map.Invoke List.cons xs <*> x
+       List.fold cons_f (result []) (loop [] t)
 
     static member inline Traverse (t:_ []      ,f , [<Optional>]_output: 'R, [<Optional>]_impl: Traverse) : 'R =
-        let cons x y = Array.append [|x|] y
-        let rec loop acc = function
-            | [||] -> acc
-            | xxs ->
-                let x, xs = Array.head xxs, Array.tail xxs
-                let v = f x
-                loop (cons v acc) xs
-        let cons_f x xs = Map.Invoke cons xs <*> x
-        Array.fold cons_f (result [||]) (loop [||] t)
+       #if TEST_TRACE
+       Traces.add "Traverse []"
+       #endif
+
+       let cons x y = Array.append [|x|] y
+       let rec loop acc = function
+           | [||] -> acc
+           | xxs ->
+               let x, xs = Array.head xxs, Array.tail xxs
+               let v = f x
+               loop (cons v acc) xs
+       let cons_f x xs = Map.Invoke cons xs <*> x
+       Array.fold cons_f (result [||]) (loop [||] t)
 
     static member inline Invoke (f: 'T->'``Functor<'U>``) (t: '``Traversable<'T>``) : '``Functor<'Traversable<'U>>`` =
         let inline call_3 (a: ^a, b: ^b, c: ^c, f) = ((^a or ^b or ^c) : (static member Traverse : _*_*_*_ -> _) b, f, c, a)

tests/FSharpPlus.Tests/FSharpPlus.Tests.fsproj

@@ -10,6 +10,7 @@
     <IsPackable>false</IsPackable>
     <Configurations>Debug;Release;Fable;Test</Configurations>
     <Platforms>AnyCPU</Platforms>
+    <DefineConstants Condition=" '$(Configuration)' == 'Test'">$(DefineConstants);TEST_TRACE</DefineConstants>
     <DefineConstants Condition=" '$(Configuration)' == 'Fable'">$(DefineConstants);FABLE_COMPILER</DefineConstants>
     <TargetFramework>net7.0</TargetFramework>
   </PropertyGroup>

tests/FSharpPlus.Tests/Traversals.fs

@@ -12,6 +12,9 @@ open Helpers
 open FSharpPlus.Math.Applicative
 open CSharpLib
 open System.Threading.Tasks
+#if TEST_TRACE
+open FSharpPlus.Internals
+#endif
 
 module Traversable =
 
@@ -251,9 +254,15 @@ module Traversable =
 
     [<Test>]
     let traverseTask () =
+        #if TEST_TRACE
+        Traces.reset()
+        #endif
         let a = traverse Task.FromResult [1;2]
         CollectionAssert.AreEqual ([1;2], a.Result)
         Assert.IsInstanceOf<Option<list<int>>> (Some a.Result)
+        #if TEST_TRACE
+        CollectionAssert.AreEqual (["Traverse list"], Traces.get())
+        #endif
         let b = map Task.FromResult [1;2] |> sequence
         CollectionAssert.AreEqual ([1;2], b.Result)
         Assert.IsInstanceOf<Option<list<int>>> (Some b.Result)
@@ -266,6 +275,9 @@ module Traversable =
 
     [<Test>]
     let traverseMap () =
+        #if TEST_TRACE
+        Traces.reset()
+        #endif
         let m = Map.ofList [("a", 1); ("b", 2); ("c", 3)]
         let r1 = traverse (fun i -> if i = 2 then None else Some i) m
         let r2 = traverse Some m
@@ -278,14 +290,23 @@ module Traversable =
                         Map.ofList [(1, 1); (2, 2)]; Map.ofList [(1, 1); (2, 2)]; Map.ofList [(1, 1); (2, 2)]]
         let actual = sequence m1
         CollectionAssert.AreEqual (expected, actual)
+        #if TEST_TRACE
+        CollectionAssert.AreEqual (["Traverse Map";"Traverse Map"], Traces.get())
+        #endif
 
     [<Test>]
     let traverseResults () =
+        #if TEST_TRACE
+        Traces.reset()
+        #endif
         let a = sequence (if true then Ok [1] else Error "no")
         let b = traverse id (if true then Ok [1] else Error "no")
         let expected: Result<int, string> list = [Ok 1]
         CollectionAssert.AreEqual (expected, a)
         CollectionAssert.AreEqual (expected, b)
+        #if TEST_TRACE
+        CollectionAssert.AreEqual (["Traverse Result";"Traverse Result"], Traces.get())
+        #endif
 
 
 module Bitraversable =