env GO111MODULE=on

# sync removes unused y, but everything else is used
go mod -sync -v
stderr '^unused y.1'
! stderr '^unused [^y]'

go list -m all
! stdout '^y'
stdout '^w.1 v1.2.0'
stdout '^z.1 v1.2.0'

-- go.mod --
module m

require (
	x.1 v1.0.0
	y.1 v1.0.0
	w.1 v1.2.0
)

replace x.1 v1.0.0 => ../x
replace y.1 v1.0.0 => ../y
replace z.1 v1.1.0 => ../z
replace z.1 v1.2.0 => ../z
replace w.1 => ../w

-- m.go --
package m

import _ "x.1"
import _ "z.1/sub"

-- w/go.mod --
module w

-- w/w.go --
package w

-- x/go.mod --
module x
require w.1 v1.1.0
require z.1 v1.1.0

-- x/x.go --
package x
import _ "w.1"

-- y/go.mod --
module y
require z.1 v1.2.0

-- z/go.mod --
module z

-- z/sub/sub.go --
package sub