From the testing docs:
"The package is built in a temporary directory so it does not interfere with the non-test installation."
So any code working with directories relative to the executable will not be present relative to Temp\go-build......
In other words, given the following:
.\helloplanet.go
.\planets\planetary.res
.\helloplanet_test.go
go test
Produces an exe in Temp\go-build... but it doesn't also re-create a planets\ subdir there, so any code in helloplanet.exe looking for planets\planetary.res of course won't find it.
How should one deal with this?