diff --git a/.hgignore b/.hgignore
--- a/.hgignore
+++ b/.hgignore
@@ -17,3 +17,4 @@ MonoPlay/bin/
 MonoPlay/obj/
 Implab.Test/Implab.Format.Test/bin/
 Implab.Test/Implab.Format.Test/obj/
+*.suo
diff --git a/Implab.Test/Implab.Test.csproj b/Implab.Test/Implab.Test.csproj
--- a/Implab.Test/Implab.Test.csproj
+++ b/Implab.Test/Implab.Test.csproj
@@ -62,8 +62,10 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="AsyncTests.cs" />
+    <Compile Include="CancelationTests.cs" />
     <Compile Include="PromiseHelper.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="RunnableComponentTests.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Implab\Implab.csproj">
diff --git a/Implab.Test/RunnableComponentTests.cs b/Implab.Test/RunnableComponentTests.cs
--- a/Implab.Test/RunnableComponentTests.cs
+++ b/Implab.Test/RunnableComponentTests.cs
@@ -9,7 +9,7 @@ using Implab.Components;
 using NUnit.Framework;
 using TestClassAttribute = NUnit.Framework.TestFixtureAttribute;
 using TestMethodAttribute = NUnit.Framework.TestAttribute;
-
+using AssertFailedException = NUnit.Framework.AssertionException;
 #else
 
 using Microsoft.VisualStudio.TestTools.UnitTesting;
@@ -23,8 +23,8 @@ namespace Implab.Test {
         static void ShouldThrow(Action action) {
             try {
                 action();
-                Assert.Fail();
-            } catch(AssertionException) {
+                Assert.Fail();
+            } catch (AssertFailedException) {
                 throw;
             } catch {
             }
@@ -131,7 +131,8 @@ namespace Implab.Test {
             p.Cancel();
             ShouldThrow(() => p.Join(1000));
             Assert.AreEqual(ExecutionState.Failed, comp.State);
-            Assert.IsInstanceOfType(typeof(OperationCanceledException), comp.LastError);
+
+            Assert.IsInstanceOfType(comp.LastError, typeof(OperationCanceledException));
 
             comp.Dispose();
         }
@@ -183,8 +184,8 @@ namespace Implab.Test {
             Assert.AreEqual(ExecutionState.Stopping, comp.State);
             p.Cancel();
             ShouldThrow(() => p.Join(1000));
-            Assert.AreEqual(ExecutionState.Failed, comp.State);
-            Assert.IsInstanceOfType(typeof(OperationCanceledException), comp.LastError);
+            Assert.AreEqual(ExecutionState.Failed, comp.State);
+            Assert.IsInstanceOfType(comp.LastError, typeof(OperationCanceledException));
 
             comp.Dispose();
         }