McpServerStartsSuccessfullyViaStdio unit test fails randomly

[vladascibulskis]

Another test that fails randomly:

Assert.IsNotNull failed. 'value' expression: 'response'. Should receive a response from MCP server.
at Microsoft.VisualStudio.TestTools.UnitTesting.Assert.IsNotNull(Object value, String message, String valueExpression)
at Verifiable.Tests.ToolTests.McpServerTests.McpServerStartsSuccessfullyViaStdio() (file:///Users/vladascibulskis/Verifiable/test/Verifiable.Tests/ToolTests/McpServerTests.cs#L299,0)
at Verifiable.Tests.ToolTests.McpServerTests.McpServerStartsSuccessfullyViaStdio() (file:///Users/vladascibulskis/Verifiable/test/Verifiable.Tests/ToolTests/McpServerTests.cs#L315,0)
at Microsoft.VisualStudio.TestPlatform.MSTest.TestAdapter.Execution.TestMethodInfo.ExecuteInternalAsync(Object[] arguments, CancellationTokenSource timeoutTokenSource)

I believe it happens when test hits this 5s timeout:
using var cts = CancellationTokenSource.CreateLinkedTokenSource(TestContext.CancellationToken); cts.CancelAfter(TimeSpan.FromSeconds(5)); string? response = await VerifiableCliTestHelpers.ReadLineWithTimeoutAsync(process.StandardOutput, cts.Token);

It happens only when I run the whole test suite. This test take ±5s+ and usually succeeds, but fails if it takes 7s+
If I run only this test it executes in half a second and I couldn't make it fail.
It is quite strange why single test is executing so much faster compared to when it's part of the whole suite. Is it because tests are running in parallel and multiple tests are starting same executable process?

[veikkoeeva]

Oh, sorry, @vladascibulskis, I didn't notice this. May I ask you try again? I had written some not so good code on MCP tests initially as I was just pushing it out of the gate for other purposes. I think I've fixed this (and few other similar).