Add test

test/NuGet.Core.Tests/NuGet.Protocol.Tests/Plugins/PluginFactoryTests.cs

@@ -2,8 +2,11 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.IO;
+using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
+using NuGet.Test.Utility;
 using Xunit;
 
 namespace NuGet.Protocol.Plugins.Tests
@@ -135,6 +138,100 @@ public async Task GetOrCreateAsync_ThrowsIfDisposed()
             Assert.Equal(nameof(PluginFactory), exception.ObjectName);
         }
 
+        [PlatformFact(Platform.Windows)]
+        public async Task GetOrCreateNetPluginAsync_CreatesPluginAndSendsHandshakeRequest()
+        {
+            using TestDirectory testDirectory = TestDirectory.Create();
+            string pluginPath = Path.Combine(testDirectory.Path, "nuget-plugin-batFile.bat");
+
+            string outputFilePath = Path.Combine(testDirectory.Path, "output.txt");
+            File.WriteAllText(outputFilePath, "");
+
+            // Create the .bat file that simulates a plugin
+            // Simply waits for a json request that looks like`{"RequestId":"ff52f0ae-28c9-4a19-957d-78db5b68f3f2","Type":"Request","Method":"Handshake","Payload":{"ProtocolVersion":"2.0.0","MinimumProtocolVersion":"1.0.0"}} `
+            // and sends it back with the type changed to `Response`
+            string batFileContent = $@"
+@echo off
+setlocal enabledelayedexpansion
+
+set outputFile={outputFilePath}
+
+:: Clear the output file initially (if it exists)
+echo. > %outputFile%
+
+:: Initialize the counter for '}}' characters
+set closingBraceCount=0
+
+:loop
+
+:: Read from stdin (standard input)
+set /p input=""""
+
+:: Count occurrences of '}}' in the input
+for /l %%i in (0,1,1023) do (
+    if ""!input:~%%i,1!""==""}}"" (
+        set /a closingBraceCount+=1
+    )
+)
+
+:: Write the input to the output file
+echo !input! >> %outputFile%
+
+:: If '}}' has appeared twice (even across multiple inputs), process the output file
+if !closingBraceCount! geq 2 (
+    goto processOutput
+)
+
+:: Go back to the loop to accept more input
+goto loop
+
+:processOutput
+
+for /f ""delims="" %%a in (%outputFile%) do (
+    set ""singleLine=!singleLine! %%a""
+)
+
+:: Perform string replacement (""Request"" -> ""Response"") in the single line
+set modifiedLine=!singleLine:""Type"":""Request""=""Type"":""Response""!
+
+echo !modifiedLine!
+";
+            File.WriteAllText(pluginPath, batFileContent);
+
+            var args = PluginConstants.PluginArguments;
+            var reqHandler = new RequestHandlers();
+            var options = ConnectionOptions.CreateDefault();
+
+            var pluginFactory = new PluginFactory(Timeout.InfiniteTimeSpan);
+
+            // Act
+            var plugin = Assert.ThrowsAsync<PluginException>(() => pluginFactory.GetOrCreateNetToolsPluginAsync(pluginPath, args, reqHandler, options, CancellationToken.None));
+            await Task.Delay(10);
+
+            // Assert
+            Assert.NotNull(plugin);
+            string jsonOutput = File.ReadAllText(outputFilePath);
+            var jsonDocument = JsonDocument.Parse(jsonOutput);
+            var rootElement = jsonDocument.RootElement;
+            if (rootElement.TryGetProperty("Method", out JsonElement methodElement))
+            {
+                Assert.Equal("Handshake", methodElement.GetString());
+            }
+            else
+            {
+                Assert.Fail("The Method property was not found in the JSON output.");
+            }
+
+            if (rootElement.TryGetProperty("Type", out JsonElement typeElement))
+            {
+                Assert.Equal("Request", typeElement.GetString());
+            }
+            else
+            {
+                Assert.Fail("The Type property was not found in the JSON output.");
+            }
+        }
+
         [Fact]
         public async Task CreateFromCurrentProcessAsync_ThrowsForNullRequestHandlers()
         {