[short] skip
[gccgo] skip # gccgo has no cover tool

go test -coverpkg=coverdot/a,coverdot/b coverdot/b
! stderr '[^0-9]0\.0%'
! stdout '[^0-9]0\.0%'

-- go.mod --
module coverdot

go 1.16
-- a/a.go --
package a

func F() {}
-- b/b.go --
package b

import . "coverdot/a"

func G() { F() }
-- b/b_test.go --
package b

import "testing"

func TestG(t *testing.T) {
	G()
}