Adding repros for issues #26 and #31

Incorrectly resolving arg matchers with default args (#31)
Reentrant setting of return values (#26)
Cleaned up code tokens from previous documentation approach.

Source/NSubstitute.Acceptance.Specs/ParameterMatching.cs

@@ -1,4 +1,5 @@
-using NUnit.Framework;
+using NSubstitute.Exceptions;
+using NUnit.Framework;
 
 namespace NSubstitute.Acceptance.Specs
 {
@@ -106,6 +107,20 @@ public void Received_should_compare_elements_for_params_arguments()
             _something.DidNotReceive().WithParams(1, Arg.Is<string[]>(x => x.Length > 3));
         }
 
+        [Test]
+        [Pending]
+        public void Throw_with_ambiguous_arguments_when_given_an_arg_matcher_and_a_default_arg_value()
+        {
+            Assert.Throws<AmbiguousArgumentsException>(() =>
+               {
+                   _something.Add(0, Arg.Any<int>()).Returns(1);
+                   //Should not make it here, as it can't work out which arg the matcher refers to.
+                   //If it does this will throw an AssertionException rather than AmbiguousArgumentsException.
+                   Assert.That(_something.Add(0, 5), Is.EqualTo(1));
+               }
+                );
+        }
+
         [Test]
         [Pending]
         public void Resolve_setter_arg_matcher_with_more_specific_type_than_member_signature()

Source/NSubstitute.Acceptance.Specs/SimpleSubstituteExamples.cs

@@ -6,7 +6,6 @@ namespace NSubstitute.Acceptance.Specs
     [TestFixture]
     public class SimpleSubstituteExamples
     {
-        /* {CODE:Use_a_shiny_new_substitute} */
         [Test]
         public void Use_a_shiny_new_substitute()
         {
@@ -23,7 +22,6 @@ public void Tell_a_substitute_to_return_a_value()
             Assert.That(calculator.Add(1, 2), Is.EqualTo(3));
         }
 
-        /* {CODE:Return_different_values_for_different_arguments} */
         [Test]
         public void Return_different_values_for_different_arguments()
         {
@@ -45,7 +43,6 @@ public void Return_a_value_evaluated_at_runtime()
             Assert.That(calculator.Add(-1, -2), Is.EqualTo(-3));
         }
 
-        /* {CODE:Check_a_call_was_received} */
         [Test]
         public void Check_a_call_was_received()
         {

Source/NSubstitute.Acceptance.Specs/SubstituteTimingAndInteractions.cs

@@ -3,23 +3,49 @@
 
 namespace NSubstitute.Acceptance.Specs
 {
-    [TestFixture]
     public class SubstituteTimingAndInteractions
     {
-        [Test]
-        public void Update_a_property_on_a_substitute_while_it_is_raising_an_event()
+        public class When_updating_a_property_on_a_sub_from_an_event_handler
         {
-            var firstMate = Substitute.For<IICapn>();
-            firstMate.HoistTheMainSail += () => firstMate.IsMainSailHoisted = true;
+            public interface IICapn
+            {
+                event Action HoistTheMainSail;
+                bool IsMainSailHoisted { get; set; }
+            }
 
-            firstMate.HoistTheMainSail += Raise.Action();
-            Assert.That(firstMate.IsMainSailHoisted, Is.True);
-        }   
+            [Test]
+            public void Should_update_the_property_when_the_event_is_raised()
+            {
+                var firstMate = Substitute.For<IICapn>();
+                firstMate.HoistTheMainSail += () => firstMate.IsMainSailHoisted = true;
 
-        public interface IICapn
+                firstMate.HoistTheMainSail += Raise.Action();
+                Assert.That(firstMate.IsMainSailHoisted, Is.True);
+            }
+        }
+
+        public class When_setting_the_return_value_of_one_sub_within_the_call_to_set_a_return_on_another
         {
-            event Action HoistTheMainSail;
-            bool IsMainSailHoisted { get; set; }
+
+            public interface IWidget { string GetName(); }
+            public interface IWidgetFactory { IWidget CreateWidget(); }
+
+            [Test][Pending]
+            public void Should_set_both_calls_to_return_the_specified_values()
+            {
+                const string widgetName = "widget x";
+                var factory = Substitute.For<IWidgetFactory>();
+                factory.CreateWidget().Returns(CreateSubstituteForWidget(widgetName));
+
+                Assert.That(factory.CreateWidget().GetName(), Is.EqualTo(widgetName));
+            }
+
+            IWidget CreateSubstituteForWidget(string widgetName)
+            {
+                var widget = Substitute.For<IWidget>();
+                widget.GetName().Returns(widgetName);
+                return widget;
+            }
         }
     }
 }