Merge from master.

Author: kurtschelfthout

FsCheck Release Notes.md

@@ -6,6 +6,8 @@
 
 * Add a few missing `Prop.ForAll` overloads.
 
+* Includes changes in 2.16.4.
+
 
 ### 3.0.0-beta1 - 5 September 2021
 
@@ -67,6 +69,12 @@
 
 * Simplify sampling data: Gen.sample et al.
 
+### 2.16.4 - 8 January 2022
+
+* Fixed display issue affecting custom F# exceptions.
+
+* `Prop.throws` now fails the test if an unexpected exception is thrown.
+
 ### 2.16.3 - 4 September 2021
 
 * Allow configuration in FsCheck.Xunit.PropertiesAttribute to affect properties on nested types or modules. PropertiesAttribute on the closest enclosing type takes precedence.

docs/QuickStart.fsx

@@ -14,7 +14,7 @@ with existing test frameworks like NUnit, xUnit.NET or MsTest.
 
 First install FsCheck, open an fsx file and start with:*)
 
-#r "FsCheck"
+#r "nuget:FsCheck"
 
 open FsCheck
 

src/FsCheck/FSharp.Prop.fs

@@ -24,7 +24,15 @@ module Prop =
     ///and a failure otherwise.
     [<CompiledName("Throws")>]
     let throws<'Exception, 'Testable when 'Exception :> exn> (p : Lazy<'Testable>) = 
-       property <| try ignore p.Value; Res.failedFalse with :? 'Exception -> Res.passed
+       try 
+           ignore p.Value
+           Res.failedException (exn "Expected exception, none was thrown") 
+       with 
+           | :? 'Exception -> 
+               Res.passed
+           | e ->
+               Res.failedException e
+       |> property
 
     let private stamp str = 
         let add res = 

src/FsCheck/Runner.fs

@@ -522,7 +522,7 @@ module Runner =
                     name data.NumberOfTests (pluralize data.NumberOfTests) (data.Stamps |> stampsToString)
         | TestResult.Failed (data, originalArgs, args, Outcome.Failed exc, originalSeed, lastSeed, lastSize) -> 
             onFailureToString name data originalArgs args originalSeed lastSeed lastSize
-            + sprintf "with exception:%s%O%s" newline exc newline
+            + sprintf "with exception:%s%A%s" newline exc newline
         | TestResult.Failed (data, originalArgs, args, _, originalSeed, lastSeed, lastSize) -> 
             onFailureToString name data originalArgs args originalSeed lastSeed lastSize
         | TestResult.Exhausted data -> 

tests/FsCheck.Test/Property.fs

@@ -142,10 +142,17 @@ module Property =
             override __.OnFinished(_,testResult) = 
                 result <- Some testResult
 
+    let private checkResult (prop:Property) =
+        let resultRunner = GetResultRunner()
+        let config = Config.Quick.WithRunner(resultRunner).WithMaxTest(2)
+        Check.One(config, prop)
+        resultRunner.Result
+
     [<Property>]
     let DSL() = 
         Prop.forAll (Arb.fromGen symPropGen) (fun symprop ->
             let expected = determineResult symprop
+            let actual = checkResult (toProperty symprop)
             let resultRunner = GetResultRunner()
             let config = Config.Quick.WithRunner(resultRunner).WithMaxTest(2)
             Check.One(config,toProperty symprop)
@@ -196,3 +203,18 @@ module Property =
                 | TestResult.Passed _ -> false
                 | TestResult.Failed _ -> true
                 | TestResult.Exhausted _ -> false @>
+
+    [<Fact>]
+    let ``throws should fail on unexpected exception``() =
+        let test() =
+            (lazy invalidOp "boom")
+            |> Prop.throws<ArgumentException, _>
+            |> Prop.label "Expected ArgumentException"
+        let actual = checkResult (Prop.ofTestable test)
+        match actual with
+        | TestResult.Failed (td,_,_,Outcome.Failed e,_,_,_) when (e :? InvalidOperationException) -> 
+            if not (td.Labels.Contains("Expected ArgumentException")) then
+                failwith "Expected label to be applied"
+        | t -> failwithf "Expected failing test with exception, got %A" t
+
+