env GO111MODULE=on

# After 'go get', the go.sum file should contain the sum for the module.
go get rsc.io/quote@v1.5.0
grep 'rsc.io/quote v1.5.0' go.sum

# If we replace the module and run 'go mod tidy', we should get a sum for the replacement.
go mod edit -replace rsc.io/quote@v1.5.0=rsc.io/quote@v1.5.1
go mod tidy
grep 'rsc.io/quote v1.5.1' go.sum
cp go.sum go.sum.tidy

# 'go mod vendor' should preserve that sum, and should not need to add any new entries.
go mod vendor
grep 'rsc.io/quote v1.5.1' go.sum
cmp go.sum go.sum.tidy

-- go.mod --
module golang.org/issue/27868

require rsc.io/quote v1.5.0

-- main.go --
package main

import _ "rsc.io/quote"

func main() {}