Follow up to fixing async symbol support

Changing signature of ISourceInformationProvider to work with MethodInfo
instead.

Also cleaning up some little issues in unit tests and adding a few
[NotNull]s that were needed.

src/Microsoft.Dnx.TestAdapter/ISourceInformationProvider.cs

@@ -1,10 +1,13 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System.Reflection;
+using Microsoft.Framework.Internal;
+
 namespace Microsoft.Dnx.TestAdapter
 {
     public interface ISourceInformationProvider
     {
-        SourceInformation GetSourceInformation(string className, string methodName);
+        SourceInformation GetSourceInformation([NotNull] MethodInfo method);
     }
 }

src/Microsoft.Dnx.TestAdapter/ITestDiscoverySink.cs

@@ -1,10 +1,12 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using Microsoft.Framework.Internal;
+
 namespace Microsoft.Dnx.TestAdapter
 {
     public interface ITestDiscoverySink
     {
-        void SendTest(Test test);
+        void SendTest([NotNull] Test test);
     }
 }

src/Microsoft.Dnx.TestAdapter/ITestExecutionSink.cs

@@ -1,12 +1,14 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using Microsoft.Framework.Internal;
+
 namespace Microsoft.Dnx.TestAdapter
 {
     public interface ITestExecutionSink
     {
-        void RecordStart(Test test);
+        void RecordStart([NotNull] Test test);
 
-        void RecordResult(TestResult testResult);
+        void RecordResult([NotNull] TestResult testResult);
     }
 }

src/Microsoft.Dnx.TestHost/TestAdapter/SourceInformationProvider.cs

@@ -35,7 +35,7 @@ public SourceInformationProvider(
             _logger = logger;
         }
 
-        public SourceInformation GetSourceInformation(string className, string methodName)
+        public SourceInformation GetSourceInformation(MethodInfo method)
         {
             if (!EnsureInitialized())
             {
@@ -57,12 +57,10 @@ public SourceInformation GetSourceInformation(string className, string methodNam
             // Note that this doesn't deal gracefully with overloaded methods. Symbol APIs don't provide
             // a way to match overloads. We'd really need MetadataTokens to do this correctly (missing in
             // CoreCLR).
-            var method = ResolveBestMethodInfo(className, methodName);
-            if (method != null)
-            {
-                className = method.DeclaringType.FullName;
-                methodName = method.Name;
-            }
+            method = ResolveBestMethodInfo(method);
+
+            var className = method.DeclaringType.FullName;
+            var methodName = method.Name;
 
             // The DIA code doesn't include a + for nested classes, just a dot.
             var symbolId = FindMethodSymbolId(className.Replace('+', '.'), methodName);
@@ -83,22 +81,10 @@ public SourceInformation GetSourceInformation(string className, string methodNam
             }
         }
 
-        private MethodInfo ResolveBestMethodInfo(string className, string methodName)
+        private MethodInfo ResolveBestMethodInfo(MethodInfo method)
         {
             Debug.Assert(_isInitialized == true);
 
-            var @class = _assembly.GetType(className);
-            if (@class == null)
-            {
-                return null;
-            }
-
-            var method = @class.GetMethods().Where(m => m.Name == methodName).FirstOrDefault();
-            if (method == null)
-            {
-                return null;
-            }
-
             // If a method has a StateMachineAttribute, then all of the user code will show up 
             // in the symbols associated with the compiler-generated code. So, we need to look
             // for the 'MoveNext' on the generated type and resolve symbols for that.

test/Microsoft.Dnx.TestHost.Tests/TestHostTest.cs

@@ -53,15 +53,14 @@ public async Task ListTest()
             var fullMessageDiagnostics = string.Format("Full output: \n{0}", string.Join("\n", host.Output));
             var testOutput = host.Output.Where(message => message.MessageType != "Log");
 
-            Assert.True(10 == testOutput.Count(), "Output count is not 8. \n" + fullMessageDiagnostics);
+            Assert.True(10 == testOutput.Count(), "Number of messages is not right. \n" + fullMessageDiagnostics);
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.True_is_true"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest1(x: 1)"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest1(x: 2)"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest1(x: 3)"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest2(x: 1, s: \"Hi\")"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest2(x: 2, s: \"Hi\")"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest2(x: 3, s: \"Hi\")"));
-            Assert.Single(host.Output, m => TestFound(m, "SampleTest.TheoryTest2(x: 3, s: \"Hi\")"));
             Assert.Single(host.Output, m => TestFound(m, "SampleTest.SampleAsyncTest"));
             Assert.Single(host.Output, m => TestFound(m, "DerivedTest.ThisGetsInherited"));
             Assert.Equal("TestDiscovery.Response", host.Output[host.Output.Count - 1].MessageType);