Ensure Returns(InvocationFunc) doesn't throw TargetInvocationException

CHANGELOG.md

@@ -15,6 +15,7 @@ The format is loosely based on [Keep a Changelog](http://keepachangelog.com/en/1
 * `AmbiguousMatchException` raised when interface has property indexer besides property in VB. (@mujdatdinc, #1129)
 * Interface default methods are ignored (@hahn-kev, #972)
 * Callback validation too strict when setting up a task's `.Result` property (@stakx, #1132)
+* `setup.Returns(InvocationFunc)` wraps thrown exceptions in `TargetInvocationException` (@stakx, #1141)
 
 
 ## 4.16.0 (2021-01-16)

src/Moq/MethodCall.cs

@@ -247,7 +247,7 @@ public void SetReturnComputedValueBehavior(Delegate valueFactory)
  }
  else if (IsInvocationFunc(valueFactory))
  {
- this.returnOrThrow = new ReturnComputedValue(invocation => valueFactory.DynamicInvoke(invocation));
+ this.returnOrThrow = new ReturnComputedValue(invocation => valueFactory.InvokePreserveStack(new object[] { invocation }));
  }
  else
  {

tests/Moq.Tests/CallbacksFixture.cs

@@ -516,6 +516,19 @@ public void CallbackWithMultipleArgumentIndexerSetterWithoutAny()
  Assert.Equal(2, result);
  }
 
+ [Fact]
+ public void Type_of_exception_thrown_from_InvocationFunc_callback_should_be_preserved()
+ {
+ var mock = new Mock<IFoo>();
+ mock.Setup(m => m.Submit("good", "bad")).Returns(new InvocationFunc(invocation =>
+ {
+ throw new Exception("very bad"); // this used to be erroneously wrapped as a `TargetInvocationException`
+ }));
+
+ var ex = Assert.Throws<Exception>(() => mock.Object.Submit("good", "bad"));
+ Assert.Equal("very bad", ex.Message);
+ }
+
  public interface IInterface
  {
  void Method(Derived b);