Allow go get -u to upgrade replacements

[andig]

What version of Go are you using (go version)?

$ go version
go version go1.12.7 darwin/amd64

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
❯ go env
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/andig/Library/Caches/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/andig/htdocs/go"
GOPROXY="https://proxy.golang.org"
GORACE=""
GOROOT="/usr/local/opt/go/libexec"
GOTMPDIR=""
GOTOOLDIR="/usr/local/opt/go/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/Users/andig/htdocs/mbmd/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/w5/_c0nb6n90fn96tzw04dtc6240000gn/T/go-build121491140=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

I'm using a module replacement:

replace github.com/crabmusket/gosunspec => github.com/andig/gosunspec v0.0.0-20190802074646-9596f4c956e3

Doing

go get -u github.com/andig/gosunspec@rollup

does not update the replacement I have in go.mod to the latest commit available. Instead, it adds it as new requirements.

What did you expect to see?

It would be nice if the replacements allowed upgrading too. Currently it doesn't, instead it adds the module to the required modules and I manually need copy the commit across to the replacement line plus remove the added module.

Granted this is probably not too common but would be nice.

[shivi28]

@andig Do you have require github.com/crabmusket/gosunspec in your go.mod file. Please check this #29299 PR for reference. It might be useful for you.

[andig]

Do you have require github.com/crabmusket/gosunspec in your go.mod file

Yes, I do (https://github.com/volkszaehler/mbmd/blob/master/go.mod#L4).

I've read both #29299 and #26241 now, it seems they are about not having to write the actual require when using replace.
Neither seems to mention the missing upgrade behaviour of go get -u with replace?

[bcmills]

Duplicate of #32721