IOException: The file 'obj\Debug\net35\annotated\System.Core.xml' already exists.

[jnm2]

error MSB4018: The "AnnotatorBuildTask" task failed unexpectedly.
System.IO.IOException: The file 'obj\Debug\net35\annotated\System.Core.xml' already exists.

at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.File.InternalCopy(String sourceFileName, String destFileName, Boolean overwrite, Boolean checkHost)
at System.IO.File.Copy(String sourceFileName, String destFileName)
at TunnelVisionLabs.ReferenceAssemblyAnnotator.AnnotatorBuildTask.Execute()
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
at Microsoft.Build.BackEnd.TaskBuilder.<ExecuteInstantiatedTask>d__26.MoveNext()

@sharwell If the file exists, would there ever be a reason that it would need to be updated? Rather than passing overwrite: true, maybe the IOException could be swallowed based on the error code (probably ERROR_FILE_EXISTS).

[jnm2]

Not sure why this repros every single time when building NUnit in VS (no successful builds) but works from the command line. There might be something more here.

[jnm2]

Ah, just figured it out. Repeated /t:Rebuild always works. Repeated /t:Build always crashes. Maybe the targets have incremental build problems.

[jnm2]

@sharwell I can't reopen but I think there is more work here.

[jnm2]

I'm consistently reproing this in CI with alpha.154 which I thought had the fix:

%userprofile%.nuget\packages\tunnelvisionlabs.referenceassemblyannotator\1.0.0-alpha.154\build\TunnelVisionLabs.ReferenceAssemblyAnnotator.targets(120,5): error MSB4018: The "AnnotatorBuildTask" task failed unexpectedly.

System.IO.IOException: The file 'obj\Release\annotated\System.Core.xml' already exists.

at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) 
at System.IO.File.InternalCopy(String sourceFileName, String destFileName, Boolean overwrite, Boolean checkHost) 
at System.IO.File.Copy(String sourceFileName, String destFileName) 
at TunnelVisionLabs.ReferenceAssemblyAnnotator.AnnotatorBuildTask.Execute() 
at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute() 
at Microsoft.Build.BackEnd.TaskBuilder.<ExecuteInstantiatedTask>d__26.MoveNext()