env GO111MODULE=on

# downgrade sampler should downgrade quote
go get rsc.io/sampler@v1.0.0
go list -m all
stdout 'rsc.io/quote v1.4.0'
stdout 'rsc.io/sampler v1.0.0'

# downgrade sampler away should downgrade quote further
go get rsc.io/sampler@none
go list -m all
stdout 'rsc.io/quote v1.3.0'

# downgrade should report inconsistencies and not change go.mod
go get rsc.io/quote@v1.5.1
go list -m all
stdout 'rsc.io/quote v1.5.1'
stdout 'rsc.io/sampler v1.3.0'
! go get rsc.io/sampler@v1.0.0 rsc.io/quote@v1.5.2 golang.org/x/text@none
stderr 'go get: inconsistent versions:\n\trsc.io/quote@v1.5.2 requires golang.org/x/text@v0.0.0-20170915032832-14c0d48ead0c \(not golang.org/x/text@none\), rsc.io/sampler@v1.3.0 \(not rsc.io/sampler@v1.0.0\)'
go list -m all
stdout 'rsc.io/quote v1.5.1'
stdout 'rsc.io/sampler v1.3.0'

# go get -u args should limit upgrades
cp go.mod.empty go.mod
go get -u rsc.io/quote@v1.4.0 rsc.io/sampler@v1.0.0
go list -m all
stdout 'rsc.io/quote v1.4.0'
stdout 'rsc.io/sampler v1.0.0'
! stdout golang.org/x/text

-- go.mod --
module x
require rsc.io/quote v1.5.1
-- go.mod.empty --
module x
-- x.go --
package x