x/tools/gopls/internal/analysis/modernize: Suggests replacing code in the standard library which provides the modern implementation.

[renthraysk]

Go version

go version go1.24.1 linux/amd64

Output of go env in your module/workspace:

AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE=''
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/home/ren/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/home/ren/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build2397105502=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/dev/null'
GOMODCACHE='/home/ren/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/home/ren/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/home/ren/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.24.1'
GOWORK=''
PKG_CONFIG='pkg-config'

What did you do?

Open maps/maps.go from the standard library.

What did you see happen?

A suggestion to replace the implementation of maps.Copy() with a call to maps.Copy().

What did you expect to see?

No suggestion.

[gabyhelp]

Related Issues

• x/tools/gopls: modernize x/exp/maps.Clear for Go >= 1.21 #70717 (closed)
• x/tools/gopls/internal/analysis/modernize: Incorrect fix for map clone #72009 (closed)
• x/tools/gopls/internal/analysis/modernize: replacing non-equivalent code #73073 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[xieyuschen]

Hi @renthraysk , I think the modernize has supported this feature already. You can go install golang.org/x/tools/gopls/internal/analysis/modernize and then run modernize -fix <your-pkg> to fix this.

[renthraysk]

Not asking for a feature. It's a bug, modernize suggests changes to maps.Copy()'s implementation that would recurse forever.

[xieyuschen]

Not asking for a feature. It's a bug, modernize suggests changes to maps.Copy()'s implementation that would recurse forever.

Oh, sorry I understand it wrongly and you're talking about maps.Copy itself. I think we should reject these scenarios(maps.Insert and maps.Copy).

Updates: CL 653595 should already support it, but it hasn't been applied to latest yet.

[findleyr]

Closing as fixed (but not yet released).