cmd/go: downloading dependencies stuck when git tag signature is enable with an interactive editor

[Fryuni]

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

$ go version
go version go1.21.1 linux/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
GO111MODULE=''
GOARCH='amd64'
GOBIN=''
GOCACHE='/home/lotus/.cache/go-build'
GOENV='/home/lotus/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/home/lotus/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/home/lotus/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/nix/store/pvvv2lmx9m8b2n0447mljrl5xmla8r3h-go-1.21.1/share/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/nix/store/pvvv2lmx9m8b2n0447mljrl5xmla8r3h-go-1.21.1/share/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.21.1'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/dev/null'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build1926203900=/tmp/go-build -gno-record-gcc-switches'

What did you do?

My terminal has EDITOR=nvim set. go mod download gets stuck once it calls git tag and git opens NeoVim in the background.

The solution was to do EDITOR= go mod download. Maybe the EDITOR variable should be cleared when calling git.

What did you expect to see?

The command should complete

What did you see instead?

Nothing, the program is stuck. Inspecting the process tree, I see this:

[seankhliao]

Do you have other git config that interacts with the git tag command?
I also have EDITOR=nvim and this doesn't happen

[Fryuni]

The only one I have that affects git tag is tag.gpgsign=true, but that is non-interactive.
Removing that line doesn't fix the problem.

My config:

> git config --list
alias.wt=worktree
alias.wta=worktree add
alias.wtl=worktree list
alias.wtp=worktree prune
commit.gpgsign=true
core.excludesfile=/nix/store/mxxll2rqij72zfxbkh1vcs0607zjp8w9-gitignore
core.pager=/nix/store/48v25c5y058n4ql5d6lnj11givcfwbrd-delta-0.16.5/bin/delta
delta.features=side-by-side line-numbers
delta.delta.navigate=true
gpg.program=/nix/store/rl8h6j7mn8zsmxvfm9qwcnb63f41pimh-gnupg-2.4.1/bin/gpg2
init.defaultbranch=main
tag.gpgsign=true
url.ssh://git@github.com/.insteadof=https://github.com/
url.ssh://git@gitlab.com/.insteadof=https://gitlab.com/
user.email=luiz@lferraz.com
user.name=Luiz Ferraz
user.signingkey=2B568731DB2447EC

[bcmills]

I'm wondering why cmd/go is even running git tag at all — that seems like a weird command to run and maybe we can just not. 😅

I think it's coming from here:
https://cs.opensource.google/go/go/+/master:src/cmd/go/internal/modfetch/codehost/git.go;l=508-514;drc=d0c72c23dcb5afc80918686f18c14c870eacbd1c

It seems to me that if we know that the server has a tag ref, we should just fetch the server's refs instead of trying to recreate the tag ourselves, so that we don't (say) create a plain tag for what is an annotated tag upstream.
So perhaps instead of running git tag as a one-off we should just call r.fetchRefsLocked(ctx).

[bcmills]

@Fryuni, want to send a CL with that approach? (https://go.dev/doc/contribute)

I expect that the only tricky part will be writing a regression test — see mod_download_git_decorate_full.txt and mod_download_git_bareRepository.txt for examples of existing regression tests for bad interactions with user git configs.

[Fryuni]

I'll try it. Look out for the smoke in case something goes wrong 😄

[aaqaishtyaq]

Hey @Fryuni, Have you started working on this or can I help?

[Fryuni]

I haven't started anything on this. Its on my queue for Thursday (holiday here), but feel free to tackle it if you are interested :)

[quantonganh]

@Fryuni Could you please provide me with a minimal reproducible example?