Merge pull request #1549 from blairconrad/create-good-typed-arrays

Create properly-typed arrays
FakeItEasy · Dec 18, 2018 · c0a4099 · c0a4099
2 parents f2bef25 + 01a405b
commit c0a4099
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Showing 2 changed files with 33 additions and 2 deletions.
diff --git a/src/FakeItEasy/ExpressionExtensions.cs b/src/FakeItEasy/ExpressionExtensions.cs
@@ -1,5 +1,6 @@
 namespace FakeItEasy
 {
+    using System;
     using System.Linq.Expressions;
     using System.Reflection;
 
@@ -123,14 +124,16 @@ private static bool TryFastEvaluate(Expression expression, out object result)
 
                 case ExpressionType.NewArrayInit:
                     var newArrayExpression = (NewArrayExpression)expression;
-                    object[] arrayItems = new object[newArrayExpression.Expressions.Count];
+                    var arrayItems = Array.CreateInstance(newArrayExpression.Type.GetElementType(), newArrayExpression.Expressions.Count);
 
                     for (int i = 0; i < newArrayExpression.Expressions.Count; i++)
                     {
-                        if (!TryFastEvaluate(newArrayExpression.Expressions[i], out arrayItems[i]))
+                        if (!TryFastEvaluate(newArrayExpression.Expressions[i], out object item))
                         {
                             return false;
                         }
+
+                        arrayItems.SetValue(item, i);
                     }
 
                     result = arrayItems;

diff --git a/tests/FakeItEasy.Specs/ConfigurationSpecs.cs b/tests/FakeItEasy.Specs/ConfigurationSpecs.cs
@@ -21,6 +21,8 @@ public interface IFoo
             IFoo Bafoo();
 
             IFoo Bafoo(out int i);
+
+            IFoo Wrap(IFoo wrappee);
         }
 
         [SuppressMessage("Microsoft.Design", "CA1040:AvoidEmptyInterfaces", Justification = "It's just used for testing.")]
@@ -709,6 +711,21 @@ public static void CallsBaseMethodAndDoesNothing(BaseClass fake)
                 .x(() => exception.Should().BeAnExceptionOfType<ExpectationException>());
         }
 
+        [Scenario]
+        public static void NestedCallThatIncludesArrayConstruction(
+            IFoo fake,
+            Exception exception)
+        {
+            "Given a fake"
+                .x(() => fake = A.Fake<IFoo>());
+
+            "When I specify a call and create a non-object array in the call configuration"
+                .x(() => exception = Record.Exception(() => A.CallTo(() => fake.Wrap(Foo.BuildFromArray(new[] { 1, 2, 3 })))));
+
+            "Then it doesn't throw"
+                .x(() => exception.Should().BeNull());
+        }
+
         public class BaseClass
         {
             public bool WasCalled { get; private set; }
@@ -754,6 +771,12 @@ public sealed override int ReturnSomething()
 
         public class Foo : IFoo
         {
+            [SuppressMessage("Microsoft.Usage", "CA1801:ReviewUnusedParameters", MessageId = "integers", Justification = "Required for testing.")]
+            public static IFoo BuildFromArray(int[] integers)
+            {
+                return new Foo();
+            }
+
             public void Bar()
             {
                 throw new NotSupportedException();
@@ -778,6 +801,11 @@ public IFoo Bafoo(out int i)
             {
                 throw new NotSupportedException();
             }
+
+            public IFoo Wrap(IFoo wrappee)
+            {
+                throw new NotImplementedException();
+            }
         }
 
         public class FooFactory : DummyFactory<IFoo>