Add race detector to go test flags

[hongchaodeng]

We are trying to add -race to go test in OAM related projects.
We haven't figured out how to do it in the crossplane build scripts. Creating this issue to gather help.

[hongchaodeng]

cc @jbw976 @hasheddan @negz

[jbw976]

Hi @hongchaodeng, there is a GO_TEST_FLAGS var defined in golang.mk that should help here. https://github.com/upbound/build/blob/master/makelib/golang.mk#L35

It looks like it's passed to the invocation of go test. So maybe around https://github.com/crossplane/oam-kubernetes-runtime/blob/master/Makefile#L44, you can add the following?

GO_TEST_FLAGS += -race

[wonderflow]

@jbw976 Hi, it seems the unit test don't support race flag https://github.com/upbound/build/blob/master/makelib/golang.mk#L174

-covermode must be "atomic", not "count", when -race is enabled

How can we fix this ?

\cc @hasheddan @negz

[negz]

I suggest opening a PR against upbound/build to make the covermode configurable. Count and atomic are similar, but count is faster when the race detector is not desired.

[wonderflow]

@negz I'm not very familiar with makefile shell, could you help add that PR on upbound/build, thanks!

[wonderflow]

I have tried to send a PR upbound/build#125 , please help review thanks @negz