Added exception tests for AsyncVal

xperiandri · xperiandri · commit 95e2ca2c0948 · 2023-11-06T02:49:51.000+04:00
diff --git a/src/FSharp.Data.GraphQL.Shared/AsyncVal.fs b/src/FSharp.Data.GraphQL.Shared/AsyncVal.fs
@@ -2,6 +2,8 @@ namespace FSharp.Data.GraphQL
 
 open System
 open System.Collections.Generic
+open System.Linq
+open System.Threading.Tasks
 
 #nowarn "25"
 
@@ -15,185 +17,210 @@ type AsyncVal<'T> =
     | Async of asynchronous : Async<'T>
     | Failure of exn : Exception
 
-    static member Zero = Value(Unchecked.defaultof<'T>)
+    static member Zero = Value (Unchecked.defaultof<'T>)
     override x.ToString () =
         match x with
-        | Value v -> "AsyncVal(" + v.ToString() + ")"
+        | Value v -> "AsyncVal(" + v.ToString () + ")"
         | Async _ -> "AsyncVal(Async<>)"
         | Failure f -> "AsyncVal(Failure:" + f.Message + ")"
 
 [<RequireQualifiedAccess>]
 module AsyncVal =
 
     /// Returns true if AsyncVal wraps an Async computation, otherwise false.
-    let inline isAsync (x: AsyncVal<'T>) = match x with | Async _ -> true | _ -> false
+    let inline isAsync (x : AsyncVal<'T>) = match x with | Async _ -> true | _ -> false
 
     /// Returns true if AsyncVal contains immediate result, otherwise false.
-    let inline isSync (x: AsyncVal<'T>) = match x with | Value _ -> true | _ -> false
+    let inline isSync (x : AsyncVal<'T>) = match x with | Value _ -> true | _ -> false
 
     /// Returns true if the AsyncVal failed, otherwise false
-    let inline isFailure (x: AsyncVal<'T>) = match x with | Failure _ -> true | _ -> false
+    let inline isFailure (x : AsyncVal<'T>) = match x with | Failure _ -> true | _ -> false
 
     /// Returns value wrapped by current AsyncVal. If it's part of Async computation,
     /// it's executed synchronously and then value is returned.
     /// If the asyncVal failed, then the exception that caused the failure is raised
-    let get (x: AsyncVal<'T>) =
+    let get (x : AsyncVal<'T>) =
         match x with
         | Value v -> v
         | Async a -> a |> Async.RunSynchronously
-        | Failure f -> f.Reraise()
+        | Failure f -> f.Reraise ()
 
     /// Create new AsyncVal from Async computation.
-    let inline ofAsync (a: Async<'T>) = Async(a)
+    let inline ofAsync (a : Async<'T>) = Async (a)
 
     /// Returns an AsyncVal wrapper around provided Async computation.
-    let inline wrap (v: 'T) = Value(v)
+    let inline wrap (v : 'T) = Value (v)
 
     /// Converts AsyncVal to Async computation.
-    let toAsync (x: AsyncVal<'T>) =
+    let toAsync (x : AsyncVal<'T>) =
         match x with
         | Value v -> async.Return v
         | Async a -> a
-        | Failure f -> async.Return (f.Reraise())
+        | Failure f -> async.Return (f.Reraise ())
+
+    /// Converts AsyncVal to Async computation.
+    let toTask (x : AsyncVal<'T>) =
+        match x with
+        | Value v -> Task.FromResult (v)
+        | Async a -> Async.StartAsTask (a)
+        | Failure f -> Task.FromException<'T> (f)
 
     /// Returns an empty AsyncVal with immediatelly executed value.
     let inline empty<'T> : AsyncVal<'T> = AsyncVal<'T>.Zero
 
     /// Maps content of AsyncVal using provided mapping function, returning new
     /// AsyncVal as the result.
-    let map (fn: 'T -> 'U) (x: AsyncVal<'T>) =
+    let map (fn : 'T -> 'U) (x : AsyncVal<'T>) =
         match x with
-        | Value v -> Value(fn v)
+        | Value v -> Value (fn v)
         | Async a ->
-            Async(async {
+            Async ( async {
                 let! result = a
                 return fn result
             })
-        | Failure f -> Failure(f)
+        | Failure f -> Failure (f)
 
 
     /// Applies rescue fn in case when contained Async value throws an exception.
-    let rescue path (fn: FieldPath -> exn -> IGQLError list) (x: AsyncVal<'t>) =
+    let rescue path (fn : FieldPath -> exn -> IGQLError list) (x : AsyncVal<'t>) =
         match x with
-        | Value v -> Value(Ok v)
+        | Value v -> Value (Ok v)
         | Async a ->
-            Async(async {
+            Async (async {
                 try
                     let! v = a
                     return Ok v
-                with e -> return fn path e |> Error
+                with e ->
+                    return fn path e |> Error
             })
-        | Failure f -> Value(fn path f |> Error)
+        | Failure f -> Value (fn path f |> Error)
         |> map (Result.mapError (List.map (GQLProblemDetails.OfFieldExecutionError (path |> List.rev))))
 
 
     /// Folds content of AsyncVal over provided initial state zero using provided fn.
     /// Returns new AsyncVal as a result.
-    let fold (fn: 'State -> 'T -> 'State) (zero: 'State) (x: AsyncVal<'T>) : AsyncVal<'State> =
+    let fold (fn : 'State -> 'T -> 'State) (zero : 'State) (x : AsyncVal<'T>) : AsyncVal<'State> =
         match x with
-        | Value v -> Value(fn zero v)
+        | Value v -> Value (fn zero v)
         | Async a ->
-            Async(async{
+            Async (async {
                 let! res = a
                 return fn zero res
             })
-        | Failure f -> Failure(f)
+        | Failure f -> Failure (f)
 
 
     /// Binds AsyncVal using binder function to produce new AsyncVal.
-    let bind (binder: 'T -> AsyncVal<'U>) (x: AsyncVal<'T>) : AsyncVal<'U> =
+    let bind (binder : 'T -> AsyncVal<'U>) (x : AsyncVal<'T>) : AsyncVal<'U> =
         match x with
         | Value v -> binder v
         | Async a ->
-            Async(async{
+            Async (async {
                 let! value = a
                 let bound = binder value
                 match bound with
                 | Value v -> return v
                 | Async a -> return! a
-                | Failure f -> return f.Reraise()
+                | Failure f -> return f.Reraise ()
             })
-        | Failure f -> Failure(f)
+        | Failure f -> Failure (f)
 
     /// Converts array of AsyncVals into AsyncVal with array results.
     /// In case when are non-immediate values in provided array, they are
     /// executed asynchronously, one by one with regard to their order in array.
     /// Returned array maintain order of values.
     /// If the array contains a Failure, then the entire array will not resolve
-    let collectSequential (values: AsyncVal<'T> []) : AsyncVal<'T []> =
+    let collectSequential (values : AsyncVal<'T>[]) : AsyncVal<'T[]> =
         if values.Length = 0 then Value [||]
         elif values |> Array.exists isAsync then
-            Async(async {
+            Async (async {
                 let results = Array.zeroCreate values.Length
+                let exceptions = ResizeArray values.Length
                 for i = 0 to values.Length - 1 do
                     let v = values.[i]
                     match v with
                     | Value v -> results.[i] <- v
                     | Async a ->
                         let! r = a
                         results.[i] <- r
-                    | Failure f ->
-                        results.[i] <- f.Reraise()
-                return results })
-        else Value (values |> Array.map (fun (Value v) -> v))
+                    | Failure f -> exceptions.Add f
+                match exceptions.Count with
+                | 0 -> return results
+                | 1 -> return exceptions.First().Reraise ()
+                | _ -> return AggregateException exceptions |> raise
+            })
+        else
+            let exceptions =
+                values
+                |> Array.choose (function
+                    | Failure f -> Some f
+                    | _ -> None)
+            match exceptions.Length with
+            | 0 -> Value (values |> Array.map (fun (Value v) -> v))
+            | 1 -> Failure (exceptions.First ())
+            | _ -> Failure (AggregateException exceptions)
 
     /// Converts array of AsyncVals into AsyncVal with array results.
     /// In case when are non-immediate values in provided array, they are
     /// executed all in parallel, in unordered fashion. Order of values
     /// inside returned array is maintained.
     /// If the array contains a Failure, then the entire array will not resolve
-    let collectParallel (values: AsyncVal<'T> []) : AsyncVal<'T []> =
+    let collectParallel (values : AsyncVal<'T>[]) : AsyncVal<'T[]> =
         if values.Length = 0 then Value [||]
         else
-            let indexes = List<_>(0)
-            let continuations = List<_>(0)
+            let indexes = List<_> (0)
+            let continuations = List<_> (0)
             let results = Array.zeroCreate values.Length
+            let exceptions = ResizeArray values.Length
             for i = 0 to values.Length - 1 do
                 let value = values.[i]
                 match value with
                 | Value v -> results.[i] <- v
                 | Async a ->
                     indexes.Add i
                     continuations.Add a
-                | Failure f ->
-                    results.[i] <- f.Reraise()
-            if indexes.Count = 0
-            then Value(results)
-            else Async(async {
-                let! vals = continuations |> Async.Parallel
-                for i = 0 to indexes.Count - 1 do
-                    results.[indexes.[i]] <- vals.[i]
-                return results })
+                | Failure f -> exceptions.Add f
+            match exceptions.Count with
+            | 1 -> AsyncVal.Failure (exceptions.First ())
+            | count when count > 1 -> AsyncVal.Failure (AggregateException exceptions)
+            | _ ->
+                if indexes.Count = 0 then Value (results)
+                else Async (async {
+                    let! vals = continuations |> Async.Parallel
+                    for i = 0 to indexes.Count - 1 do
+                        results.[indexes.[i]] <- vals.[i]
+                    return results
+                })
 
     /// Converts array of AsyncVals of arrays into AsyncVal with array results
     /// by calling collectParallel and then appending the results.
-    let appendParallel (values: AsyncVal<'T []> []) : AsyncVal<'T []> =
+    let appendParallel (values : AsyncVal<'T[]>[]) : AsyncVal<'T[]> =
         values
         |> collectParallel
         |> map (Array.fold Array.append Array.empty)
 
     /// Converts array of AsyncVals of arrays into AsyncVal with array results
     /// by calling collectSequential and then appending the results.
-    let appendSequential (values: AsyncVal<'T []> []) : AsyncVal<'T []> =
+    let appendSequential (values : AsyncVal<'T[]>[]) : AsyncVal<'T[]> =
         values
         |> collectSequential
         |> map (Array.fold Array.append Array.empty)
 
 type AsyncValBuilder () =
     member _.Zero () = AsyncVal.empty
     member _.Return v = AsyncVal.wrap v
-    member _.ReturnFrom (v: AsyncVal<_>) = v
-    member _.ReturnFrom (a: Async<_>) = AsyncVal.ofAsync a
-    member _.Bind (v: AsyncVal<'T>, binder: 'T -> AsyncVal<'U>) =
-        AsyncVal.bind binder v
-    member _.Bind (a: Async<'T>, binder: 'T -> AsyncVal<'U>) =
-        Async(async {
+    member _.ReturnFrom (v : AsyncVal<_>) = v
+    member _.ReturnFrom (a : Async<_>) = AsyncVal.ofAsync a
+    member _.Bind (v : AsyncVal<'T>, binder : 'T -> AsyncVal<'U>) = AsyncVal.bind binder v
+    member _.Bind (a : Async<'T>, binder : 'T -> AsyncVal<'U>) =
+        Async (async {
             let! value = a
             let bound = binder value
             match bound with
             | Value v -> return v
             | Async a -> return! a
-            | Failure f -> return f.Reraise() })
+            | Failure f -> return f.Reraise ()
+        })
 
 
 [<AutoOpen>]
@@ -203,21 +230,21 @@ module AsyncExtensions =
     let asyncVal = AsyncValBuilder ()
 
     /// Active pattern used for checking if AsyncVal contains immediate value.
-    let (|Immediate|_|) (x: AsyncVal<'T>) = match x with | Value v -> Some v | _ -> None
+    let (|Immediate|_|) (x : AsyncVal<'T>) = match x with | Value v -> Some v | _ -> None
 
     /// Active patter used for checking if AsyncVal wraps an Async computation.
-    let (|Async|_|) (x: AsyncVal<'T>) = match x with | Async a -> Some a | _ -> None
+    let (|Async|_|) (x : AsyncVal<'T>) = match x with | Async a -> Some a | _ -> None
 
     type Microsoft.FSharp.Control.AsyncBuilder with
 
-        member _.ReturnFrom (v: AsyncVal<'T>) =
+        member _.ReturnFrom (v : AsyncVal<'T>) =
             match v with
             | Value v -> async.Return v
             | Async a -> async.ReturnFrom a
             | Failure f -> async.Return (raise f)
 
-        member _.Bind (v: AsyncVal<'T>, binder) =
+        member _.Bind (v : AsyncVal<'T>, binder) =
             match v with
-            | Value v -> async.Bind(async.Return v, binder)
-            | Async a -> async.Bind(a, binder)
-            | Failure f -> async.Bind(async.Return (raise f), binder)
+            | Value v -> async.Bind (async.Return v, binder)
+            | Async a -> async.Bind (a, binder)
+            | Failure f -> async.Bind (async.Return (raise f), binder)
diff --git a/tests/FSharp.Data.GraphQL.Tests/Helpers and Extensions/AsyncValTests.fs b/tests/FSharp.Data.GraphQL.Tests/Helpers and Extensions/AsyncValTests.fs
@@ -4,6 +4,7 @@
 module FSharp.Data.GraphQL.Tests.AsyncValTests
 
 open System
+open System.Threading.Tasks
 open FSharp.Data.GraphQL
 open Xunit
 
@@ -41,6 +42,17 @@ let ``AsyncVal computation allows to bind async computations`` () =
     AsyncVal.isSync v |> equals false
     v |> AsyncVal.get |> equals 1
 
+[<Fact>]
+let ``AsyncVal computation allows to bind async computations preserving exception stack trace`` () : Task = task {
+    let! ex = throwsAsyncVal<Exception>(
+            asyncVal {
+                let! value = async { return failwith "test" }
+                return value
+            }
+        )
+    ex.StackTrace |> String.IsNullOrEmpty |> Assert.False
+}
+
 [<Fact>]
 let ``AsyncVal computation allows to bind another AsyncVal`` () =
     let v = asyncVal {
@@ -88,6 +100,28 @@ let ``AsyncVal sequential collection resolves all values in order of execution``
     v |> AsyncVal.get |> equals [| 1; 2; 3; 4 |]
     flag |> equals "b"
 
+[<Fact>]
+let ``AsyncVal sequential collection preserves exception stack trace for a single exception`` () = task {
+    let a = async { return failwith "test" }
+    let array = [| AsyncVal.wrap 1; AsyncVal.ofAsync a; AsyncVal.wrap 3 |]
+    let! ex = throwsAsyncVal<Exception>(array |> AsyncVal.collectSequential |> AsyncVal.map ignore)
+    ex.StackTrace |> String.IsNullOrEmpty |> Assert.False
+}
+
+[<Fact>]
+let ``AsyncVal sequential collection collects all exceptions into AggregareException`` () = task {
+    let ex1 = Exception "test1"
+    let ex2 = Exception "test2"
+    let array = [| AsyncVal.wrap 1; AsyncVal.Failure ex1; AsyncVal.wrap 3; AsyncVal.Failure ex2 |]
+    //let a = async { return failwith "test" }
+    //let b = async { return failwith "test" }
+    //let array = [| AsyncVal.wrap 1; AsyncVal.ofAsync a; AsyncVal.wrap 3; AsyncVal.ofAsync b |]
+    let! ex = throwsAsyncVal<AggregateException>(array |> AsyncVal.collectSequential |> AsyncVal.map ignore)
+    ex.InnerExceptions |> Seq.length |> equals 2
+    ex.InnerExceptions[0] |> equals ex1
+    ex.InnerExceptions[1] |> equals ex2
+}
+
 [<Fact>]
 let ``AsyncVal parallel collection resolves all values with no order of execution`` () =
     let mutable flag = "none"
@@ -103,3 +137,25 @@ let ``AsyncVal parallel collection resolves all values with no order of executio
     let v = array |> AsyncVal.collectParallel
     v |> AsyncVal.get |> equals [| 1; 2; 3; 4 |]
     flag |> equals "a"
+
+[<Fact>]
+let ``AsyncVal parallel collection preserves exception stack trace for a single exception`` () = task {
+    let a = async { return failwith "test" }
+    let array = [| AsyncVal.wrap 1; AsyncVal.ofAsync a; AsyncVal.wrap 3 |]
+    let! ex = throwsAsyncVal<Exception>(array |> AsyncVal.collectParallel |> AsyncVal.map ignore)
+    ex.StackTrace |> String.IsNullOrEmpty |> Assert.False
+}
+
+[<Fact>]
+let ``AsyncVal parallel collection collects all exceptions into AggregareException`` () = task {
+    let ex1 = Exception "test1"
+    let ex2 = Exception "test2"
+    let array = [| AsyncVal.wrap 1; AsyncVal.Failure ex1; AsyncVal.wrap 3; AsyncVal.Failure ex2 |]
+    //let a = async { return failwith "test" }
+    //let b = async { return failwith "test" }
+    //let array = [| AsyncVal.wrap 1; AsyncVal.ofAsync a; AsyncVal.wrap 3; AsyncVal.ofAsync b |]
+    let! ex = throwsAsyncVal<AggregateException>(array |> AsyncVal.collectParallel |> AsyncVal.map ignore)
+    ex.InnerExceptions |> Seq.length |> equals 2
+    ex.InnerExceptions[0] |> equals ex1
+    ex.InnerExceptions[1] |> equals ex2
+}
diff --git a/tests/FSharp.Data.GraphQL.Tests/Helpers.fs b/tests/FSharp.Data.GraphQL.Tests/Helpers.fs
