Add net8 SSE fallback test and align coverage run

Author: ANcpLua

SWEN3.Paperless.RabbitMq.Tests/SWEN3.Paperless.RabbitMq.Tests.csproj

@@ -43,7 +43,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Content Include="xunit.v3.runner.json" CopyToOutputDirectory="PreserveNewest"/>
+    <Compile Include="Helpers\SseTestHelpers.cs" />
   </ItemGroup>
 
 </Project>

SWEN3.Paperless.RabbitMq.Tests/Unit/SseExtensionsFallbackTests.cs

@@ -0,0 +1,70 @@
+using System.Text;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.TestHost;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using SWEN3.Paperless.RabbitMq.Sse;
+
+namespace SWEN3.Paperless.RabbitMq.Tests.Unit;
+
+public class SseExtensionsFallbackTests
+{
+#if !NET10_0_OR_GREATER
+    [Fact]
+    public async Task MapSse_OnNet8_ShouldWriteCorrectSseFormat()
+    {
+        // Arrange
+        var hostBuilder = new WebHostBuilder()
+            .ConfigureServices(services =>
+            {
+                services.AddRouting();
+                services.AddSseStream<Messages.SseTestEvent>();
+            })
+            .Configure(app =>
+            {
+                app.UseRouting();
+                app.UseEndpoints(endpoints =>
+                {
+                    endpoints.MapSse<Messages.SseTestEvent>("/sse", 
+                        e => new { id = e.Id, msg = e.Message }, 
+                        e => "test-event");
+                });
+            });
+
+        using var server = new TestServer(hostBuilder);
+        var client = server.CreateClient();
+        var sseStream = server.Host.Services.GetRequiredService<ISseStream<Messages.SseTestEvent>>();
+
+        // Act
+        // Start the request
+        var responseTask = client.GetStreamAsync("/sse");
+        
+        // Give it a moment to connect
+        await Task.Delay(50);
+        
+        // Publish an event
+        sseStream.Publish(new Messages.SseTestEvent { Id = 1, Message = "Hello" });
+        
+        // Allow processing
+        await Task.Delay(50);
+
+        // Assert
+        var stream = await responseTask;
+        using var reader = new StreamReader(stream, Encoding.UTF8);
+        
+        // Read the stream. We expect:
+        // event: test-event\n
+        // data: {"id":1,"msg":"Hello"}\n
+        // \n
+        
+        var line1 = await reader.ReadLineAsync();
+        var line2 = await reader.ReadLineAsync();
+        var line3 = await reader.ReadLineAsync();
+
+        line1.Should().Be("event: test-event");
+        line2.Should().Be("data: {\"id\":1,\"msg\":\"Hello\"}");
+        line3.Should().BeEmpty(); // The double newline
+    }
+#endif
+}