.runtimeconfig.json], offset 0 (line 1, column 1): The document is empty.

[Evangelink]

Description

We are often getting some flakiness on our generated test assets during the execution with the following error:

A JSON parsing exception occurred in [C:\src\testfx\artifacts\tmp\Debug\testsuite\2b3xH\MSTestSdk\bin\Release\net9.0\MSTestSdk.runtimeconfig.json], offset 0 (line 1, column 1): The document is empty.
  Invalid runtimeconfig.json [C:\src\testfx\artifacts\tmp\Debug\testsuite\2b3xH\MSTestSdk\bin\Release\net9.0\MSTestSdk.runtimeconfig.json] [C:\src\testfx\artifacts\tmp\Debug\testsuite\2b3xH\MSTestSdk\bin\Release\net9.0\MSTestSdk.runtimeconfig.dev.json]
  
    at Microsoft.Testing.Platform.Acceptance.IntegrationTests.Helpers.AcceptanceAssert.AssertOutputContainsSummary(TestHostResult testHostResult, Int32 failed, Int32 passed, Int32 skipped, Nullable`1 aborted, Nullable`1 minimumNumberOfTests, String callerMemberName, String callerFilePath, Int32 callerLineNumber) in C:\src\testfx\test\IntegrationTests\Microsoft.Testing.Platform.Acceptance.IntegrationTests\Helpers\AcceptanceAssert.cs:125
    at MSTest.Acceptance.IntegrationTests.SdkTests.RunTests_With_CentralPackageManagement_Standalone(String multiTfm, BuildConfiguration buildConfiguration) in C:\src\testfx\test\IntegrationTests\MSTest.Acceptance.IntegrationTests\SdkTests.cs:144

Reproduction Steps

This is some transient failure but it's happening more and more often on our acceptance tests.

Expected behavior

No error

Actual behavior

Invalid runtimeconfig.json

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

[vitek-karas]

@Evangelink what is the code doing?
Is it in stdout/stderr of some process? If so, can you please turn on host tracing and collect the trace when this happens?

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[Evangelink]

@Evangelink what is the code doing?

For our acceptance tests, we generate test projects from strings, then build them dotnet build and finally we run the produced executable. At the stage where we run, we sometimes end up with this error (not only in CI also locally) but it's always pretty randomic and flaky.

Is it in stdout/stderr of some process

StdErr of the test process (using the new platform not VSTest)

If so, can you please turn on host tracing and collect the trace when this happens?

Given it's pretty randomic, I'll probably need to always enable the trace and rerun all acceptance tests in some loop until I have something. I'll try that.

[akoeplinger]

When the error happens can you try checking if the .json is indeed empty? This smells like antivirus scanner interfering with writing the file during dotnet build.