Adding filtering support at discovery (#271)

* Filter support at discovery

* removing unnecessary line

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

@@ -7,6 +7,7 @@ namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter
     using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Discovery;
     using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Helpers;
     using Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.ObjectModel;
+    using Microsoft.VisualStudio.TestPlatform.ObjectModel;
     using Microsoft.VisualStudio.TestPlatform.ObjectModel.Adapter;
     using Microsoft.VisualStudio.TestPlatform.ObjectModel.Logging;
 
@@ -17,24 +18,30 @@ internal class UnitTestDiscoverer
         internal UnitTestDiscoverer()
         {
             this.assemblyEnumeratorWrapper = new AssemblyEnumeratorWrapper();
+            this.TestMethodFilter = new TestMethodFilter();
         }
 
+        /// <summary>
+        /// Gets or sets method filter for filtering tests
+        /// </summary>
+        private TestMethodFilter TestMethodFilter { get; set; }
+
         /// <summary>
         /// Discovers the tests available from the provided sources.
         /// </summary>
         /// <param name="sources"> The sources. </param>
         /// <param name="logger"> The logger. </param>
         /// <param name="discoverySink"> The discovery Sink. </param>
-        /// <param name="runSettings"> The run settings. </param>
+        /// <param name="discoveryContext"> The discovery context. </param>
         internal void DiscoverTests(
             IEnumerable<string> sources,
             IMessageLogger logger,
             ITestCaseDiscoverySink discoverySink,
-            IRunSettings runSettings)
+            IDiscoveryContext discoveryContext)
         {
             foreach (var source in sources)
             {
-                this.DiscoverTestsInSource(source, logger, discoverySink, runSettings);
+                this.DiscoverTestsInSource(source, logger, discoverySink, discoveryContext);
             }
         }
 
@@ -44,16 +51,16 @@ internal void DiscoverTests(
         /// <param name="source"> The source. </param>
         /// <param name="logger"> The logger. </param>
         /// <param name="discoverySink"> The discovery Sink. </param>
-        /// <param name="runSettings"> The run settings. </param>
+        /// <param name="discoveryContext"> The discovery context. </param>
         internal virtual void DiscoverTestsInSource(
             string source,
             IMessageLogger logger,
             ITestCaseDiscoverySink discoverySink,
-            IRunSettings runSettings)
+            IDiscoveryContext discoveryContext)
         {
             ICollection<string> warnings;
 
-            var testElements = this.assemblyEnumeratorWrapper.GetTests(source, runSettings, out warnings);
+            var testElements = this.assemblyEnumeratorWrapper.GetTests(source, discoveryContext?.RunSettings, out warnings);
 
             // log the warnings
             foreach (var warning in warnings)
@@ -76,10 +83,10 @@ internal virtual void DiscoverTestsInSource(
                 testElements.Count,
                 source);
 
-            this.SendTestCases(source, testElements, discoverySink);
+            this.SendTestCases(source, testElements, discoverySink, discoveryContext, logger);
         }
 
-        internal void SendTestCases(string source, IEnumerable<UnitTestElement> testElements, ITestCaseDiscoverySink discoverySink)
+        internal void SendTestCases(string source, IEnumerable<UnitTestElement> testElements, ITestCaseDiscoverySink discoverySink, IDiscoveryContext discoveryContext, IMessageLogger logger)
         {
             var shouldCollectSourceInformation = MSTestSettings.RunConfigurationSettings.CollectSourceInformation;
 
@@ -91,11 +98,25 @@ internal void SendTestCases(string source, IEnumerable<UnitTestElement> testElem
                     navigationSessions.Add(source, PlatformServiceProvider.Instance.FileOperations.CreateNavigationSession(source));
                 }
 
+                // Get filter expression and skip discovery in case filter expression has parsing error.
+                bool filterHasError = false;
+                ITestCaseFilterExpression filterExpression = this.TestMethodFilter.GetFilterExpression(discoveryContext, logger, out filterHasError);
+                if (filterHasError)
+                {
+                    return;
+                }
+
                 foreach (var testElement in testElements)
                 {
-                    object testNavigationSession;
                     var testCase = testElement.ToTestCase();
 
+                    // Filter tests based on test case filters
+                    if (filterExpression != null && filterExpression.MatchTestCase(testCase, (p) => this.TestMethodFilter.PropertyValueProvider(testCase, p)) == false)
+                    {
+                        continue;
+                    }
+
+                    object testNavigationSession;
                     if (shouldCollectSourceInformation)
                     {
                         string testSource = testElement.TestMethod.DeclaringAssemblyName ?? source;

src/Adapter/MSTest.CoreAdapter/Execution/TestExecutionManager.cs

@@ -98,7 +98,7 @@ public void RunTests(IEnumerable<string> sources, IRunContext runContext, IFrame
                 var logger = (IMessageLogger)frameworkHandle;
 
                 // discover the tests
-                this.GetUnitTestDiscoverer().DiscoverTestsInSource(source, logger, discoverySink, runContext?.RunSettings);
+                this.GetUnitTestDiscoverer().DiscoverTestsInSource(source, logger, discoverySink, runContext);
                 tests.AddRange(discoverySink.Tests);
 
                 // Clear discoverSinksTests so that it just stores test for one source at one point of time

src/Adapter/MSTest.CoreAdapter/MSTest.CoreAdapter.csproj

@@ -50,7 +50,7 @@
     <Compile Include="Execution\TestAssemblyInfo.cs" />
     <Compile Include="Execution\TestClassInfo.cs" />
     <Compile Include="ObjectModel\TestFailedException.cs" />
-    <Compile Include="Execution\TestMethodFilter.cs" />
+    <Compile Include="TestMethodFilter.cs" />
     <Compile Include="Execution\TestMethodRunner.cs" />
     <Compile Include="Execution\TypeCache.cs" />
     <Compile Include="Execution\UnitTestRunner.cs" />

src/Adapter/MSTest.CoreAdapter/MSTestDiscoverer.cs

@@ -54,7 +54,7 @@ public void DiscoverTests(
                 return;
             }
 
-            new UnitTestDiscoverer().DiscoverTests(sources, logger, discoverySink, discoveryContext?.RunSettings);
+            new UnitTestDiscoverer().DiscoverTests(sources, logger, discoverySink, discoveryContext);
         }
 
         /// <summary>

src/Adapter/MSTest.CoreAdapter/Execution/TestMethodFilter.cs → src/Adapter/MSTest.CoreAdapter/TestMethodFilter.cs

@@ -1,16 +1,16 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution
+namespace Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter
 {
     using System;
     using System.Collections.Generic;
     using System.Diagnostics;
     using System.Linq;
+    using System.Reflection;
     using Microsoft.VisualStudio.TestPlatform.ObjectModel;
     using Microsoft.VisualStudio.TestPlatform.ObjectModel.Adapter;
     using Microsoft.VisualStudio.TestPlatform.ObjectModel.Logging;
-    using Constants = Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Constants;
 
     internal class TestMethodFilter
     {
@@ -34,24 +34,24 @@ internal TestMethodFilter()
         /// <summary>
         /// Returns ITestCaseFilterExpression for TestProperties supported by adapter.
         /// </summary>
-        /// <param name="runContext">The current context of the run.</param>
-        /// <param name="testExecutionRecorder">Handler to report test messages/start/end and results.</param>
+        /// <param name="context">The current context of the run.</param>
+        /// <param name="logger">Handler to report test messages/start/end and results.</param>
         /// <param name="filterHasError">Indicates that the filter is unsupported/has an error.</param>
         /// <returns>A filter expression.</returns>
-        internal ITestCaseFilterExpression GetFilterExpression(IRunContext runContext, IMessageLogger testExecutionRecorder, out bool filterHasError)
+        internal ITestCaseFilterExpression GetFilterExpression(IDiscoveryContext context, IMessageLogger logger, out bool filterHasError)
         {
             filterHasError = false;
             ITestCaseFilterExpression filter = null;
-            if (runContext != null)
+            if (context != null)
             {
                 try
                 {
-                    filter = runContext.GetTestCaseFilter(this.supportedProperties.Keys, this.PropertyProvider);
+                    filter = (context is IRunContext) ? this.GetTestCaseFilterFromRunContext(context as IRunContext) : this.GetTestCaseFilterFromDiscoveryContext(context);
                 }
                 catch (TestPlatformFormatException ex)
                 {
                     filterHasError = true;
-                    testExecutionRecorder.SendMessage(TestMessageLevel.Error, ex.Message);
+                    logger.SendMessage(TestMessageLevel.Error, ex.Message);
                 }
             }
 
@@ -95,5 +95,34 @@ internal object PropertyValueProvider(TestCase currentTest, string propertyName)
 
             return null;
         }
+
+        /// <summary>
+        /// Gets filter expression from run context.
+        /// </summary>
+        /// <param name="context">Run context</param>
+        /// <returns>Filter expression.</returns>
+        private ITestCaseFilterExpression GetTestCaseFilterFromRunContext(IRunContext context)
+        {
+            return context.GetTestCaseFilter(this.supportedProperties.Keys, this.PropertyProvider);
+        }
+
+        /// <summary>
+        /// Gets filter expression from discovery context.
+        /// </summary>
+        /// <param name="context">Discovery context</param>
+        /// <returns>Filter expression.</returns>
+        private ITestCaseFilterExpression GetTestCaseFilterFromDiscoveryContext(IDiscoveryContext context)
+        {
+            try
+            {
+                // GetTestCaseFilter is present in DiscoveryContext but not in IDiscoveryContext interface.
+                MethodInfo methodGetTestCaseFilter = context.GetType().GetRuntimeMethod("GetTestCaseFilter", new[] { typeof(IEnumerable<string>), typeof(Func<string, TestProperty>) });
+                return (ITestCaseFilterExpression)methodGetTestCaseFilter?.Invoke(context, new object[] { this.supportedProperties.Keys, (Func<string, TestProperty>)this.PropertyProvider });
+            }
+            catch (TargetInvocationException ex)
+            {
+                throw ex.InnerException;
+            }
+        }
     }
 }