env GO111MODULE=off
[short] skip

# go clean -testcache
# should work (see golang.org/issue/29757).
cd x
go test x_test.go
go clean -testcache
go test x_test.go
! stdout 'cached'

# golang.org/issue/29100: 'go clean -testcache' should succeed
# if the cache directory doesn't exist at all.
# It should not write a testexpire.txt file, since there are no
# test results that need to be invalidated in the first place.
env GOCACHE=$WORK/nonexistent
go clean -testcache
! exists $WORK/nonexistent

-- x/x_test.go --
package x_test
import (
    "testing"
)
func TestMain(t *testing.T) {
}