Fixed issue microsoft#437 - Removed discover warnings

Author: Carlos Parra

src/Adapter/MSTest.CoreAdapter/Discovery/TypeValidator.cs

@@ -43,10 +43,15 @@ internal virtual bool IsValidTestClass(Type type, ICollection<string> warnings)
                     (this.reflectHelper.IsAttributeDefined(type, typeof(TestClassAttribute), false) ||
                     this.reflectHelper.HasAttributeDerivedFrom(type, typeof(TestClassAttribute), false)))
             {
-                var isPublic = type.GetTypeInfo().IsPublic || (type.GetTypeInfo().IsNested && type.GetTypeInfo().IsNestedPublic);
-
                 // non-public class
-                if (!isPublic)
+                if (type.GetTypeInfo().IsNotPublic ||
+                    (type.GetTypeInfo().IsNested && type.GetTypeInfo().IsNestedPrivate))
+                {
+                    return false;
+                }
+
+                // nested non-public class
+                if (type.GetTypeInfo().IsNested && !type.GetTypeInfo().IsNestedPublic)
                 {
                     var warning = string.Format(CultureInfo.CurrentCulture, Resource.UTA_ErrorNonPublicTestClass, type.FullName);
                     warnings.Add(warning);

test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Discovery/TypeValidatorTests.cs

@@ -80,12 +80,12 @@ public void IsValidTestClassShouldReturnFalseForNonPublicTestClasses()
         }
 
         [TestMethod]
-        public void IsValidTestClassShouldReportWarningForNonPublicTestClasses()
+        public void IsValidTestClassShouldNotReportWarningForNonPublicTestClasses()
         {
             this.SetupTestClass();
             this.typeValidator.IsValidTestClass(typeof(InternalTestClass), this.warnings);
-            Assert.AreEqual(1, this.warnings.Count);
-            CollectionAssert.Contains(this.warnings, string.Format(Resource.UTA_ErrorNonPublicTestClass, typeof(InternalTestClass).FullName));
+            Assert.AreEqual(0, this.warnings.Count);
+            CollectionAssert.DoesNotContain(this.warnings, string.Format(Resource.UTA_ErrorNonPublicTestClass, typeof(InternalTestClass).FullName));
         }
 
         [TestMethod]