cmd/go: go.mod has non-....v2 module path error in master

[aspacca]

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

go version devel +6bf2767cc8 Tue Jul 16 15:37:25 2019 +0000 linux/amd64
go version devel +b5df14c309 Wed Jul 17 12:57:52 2019 +0000 linux/amd64

Does this issue reproduce with the latest release?

No reproducible other than go tip
it seems introduced by 24a6ca0

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

go env Output

$ go env
GO111MODULE="auto"
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/travis/.cache/go-build"
GOENV="/home/travis/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/travis/gopath"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/travis/.gimme/versions/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/travis/.gimme/versions/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/travis/gopath/src/github.com/dutchcoders/transfer.sh/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 -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build599295724=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Run the CI pipeline on travis-ci for github.com/dutchcoders/transfer.sh
(see https://travis-ci.org/dutchcoders/transfer.sh/jobs/559620389 and https://travis-ci.org/dutchcoders/transfer.sh/jobs/559603532)

What did you expect to see?

go get -t -u -v ./... runs with no error

What did you see instead?

go get: upgrading gopkg.in/russross/blackfriday.v2@v2.0.1: gopkg.in/russross/blackfriday.v2@v2.0.1: invalid version: go.mod has non-....v2 module path "github.com/russross/blackfriday/v2" at revision v2.0.1

[FiloSottile]

/cc @bcmills @jayconrod

[bcmills]

It's unfortunate, but the error message there is not wrong.

A replace directive today means “replace the source code for module path/to/module/1 with the source code found at path/to/module/2”. It does not change the meaning of import statements, and therefore cannot reliably be used to fix incorrect import paths (see also #30831, which is similarly unfortunate).

The go.mod file in github.com/russross/blackfriday/v2 clearly declares its module path to be github.com/russross/blackfriday/v2, and if it had any internal imports you'd instead be running up against #26904.

That said, there may be something we can do for this case in the meantime.

[gopherbot]

Change https://golang.org/cl/186617 mentions this issue: cmd/go: suppress errors with '@upgrade' when the latest version is replaced

[aspacca]

yes, the message is not wrong and the module path in the go.mod of github.com/russross/blackfriday is wrong as well, and that's why I needed the replace directive in the first place

I opened the issue to point out how it's working on current release and you may or may not want to break the behaviour

[bcmills]

@aspacca, this should be fixed at head. Please let us know if you're still having trouble.

[aspacca]

@bcmills yes, build on head is now green. thank you very much, really appreciated
(ps: I will open an issue on github.com/russross/blackfriday to see if they are going to fix the go.mod on their side anyway)