Fix dotnet test detection for dlls (#51309)

Author: Youssef1313

src/Cli/dotnet/Commands/Test/VSTest/TestCommand.cs

@@ -46,7 +46,7 @@ public static int Run(ParseResult parseResult)
 
         // Fix for https://github.com/Microsoft/vstest/issues/1453
         // Run dll/exe directly using the VSTestForwardingApp
-        if (ContainsBuiltTestSources(args))
+        if (ContainsBuiltTestSources(parseResult))
         {
             return ForwardToVSTestConsole(parseResult, args, settings, testSessionCorrelationId);
         }
@@ -295,18 +295,14 @@ internal static int RunArtifactPostProcessingIfNeeded(string testSessionCorrelat
         }
     }
 
-    private static bool ContainsBuiltTestSources(string[] args)
+    private static bool ContainsBuiltTestSources(ParseResult parseResult)
     {
-        for (int i = 0; i < args.Length; i++)
+        for (int i = 0; i < parseResult.UnmatchedTokens.Count; i++)
         {
-            string arg = args[i];
-            if (arg.EndsWith(".dll", StringComparison.OrdinalIgnoreCase) || arg.EndsWith(".exe", StringComparison.OrdinalIgnoreCase))
+            string arg = parseResult.UnmatchedTokens[i];
+            if (!arg.StartsWith("-") &&
+                (arg.EndsWith(".dll", StringComparison.OrdinalIgnoreCase) || arg.EndsWith(".exe", StringComparison.OrdinalIgnoreCase)))
             {
-                var previousArg = i > 0 ? args[i - 1] : null;
-                if (previousArg != null &&  CommonOptions.PropertiesOption.Aliases.Contains(previousArg))
-                {
-                    return false;
-                }
                 return true;
             }
         }

test/dotnet.Tests/CommandTests/Test/GivenDotnetTestBuildsAndRunsTestfromCsproj.cs

@@ -836,6 +836,28 @@ public void PropertiesEndingWithDotDllShouldNotFail(string property)
             result.ExitCode.Should().Be(1);
         }
 
+        [Fact]
+        public void DistributedLoggerEndingWithDotDllShouldBePassedToMSBuild()
+        {
+            var testProjectDirectory = CopyAndRestoreVSTestDotNetCoreTestApp([]);
+
+            CommandResult result = new DotnetTestCommand(Log, disableNewOutput: true)
+                                        .WithWorkingDirectory(testProjectDirectory)
+                                        .Execute(ConsoleLoggerOutputNormal.Concat(["-dl:my.dll"]));
+
+            if (!TestContext.IsLocalized())
+            {
+                // This ensures that this was passed to MSBuild and not vstest.console.
+                result.StdOut.Should().Contain("error MSB1021: Cannot create an instance of the logger my.dll.");
+            }
+            else
+            {
+                result.StdOut.Should().Contain("MSB1021");
+            }
+
+            result.ExitCode.Should().Be(1);
+        }
+
         private string CopyAndRestoreVSTestDotNetCoreTestApp(object[] parameters, [CallerMemberName] string callingMethod = "")
         {
             // Copy VSTestCore project in output directory of project dotnet-vstest.Tests