x/tools/gopls: InvalidRangeExpr when using GOEXPERIMENT=rangefunc on iter.Seq

[stephenafamo]

gopls version

golang.org/x/tools/gopls v0.15.0-pre.2 golang.org/x/tools/[email protected] h1:A48ndEGf3pvzJ0k22HneSU7msCaggzcpg56ELTEuapQ= github.com/BurntSushi/[email protected] h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak= github.com/google/[email protected] h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI= golang.org/x/exp/[email protected] h1:2O2DON6y3XMJiQRAS1UWU+54aec2uopH3x7MAiqGW6Y= golang.org/x/[email protected] h1:dGoOF9QVLYng8IHTm7BAyWqCqSheQ5pYWGhzW00YJr0= golang.org/x/[email protected] h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ= golang.org/x/[email protected] h1:Nr7eTQpQZ/ytesxDJpQgaf0t4sdLnnDtAbmtViTrSUo= golang.org/x/[email protected] h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ= golang.org/x/[email protected] h1:WL/PnseOKWuDtRbgfYKDpuAmMpy3OrX84rv7uQFZJK4= golang.org/x/[email protected] h1:KUas02EjQK5LTuIx1OylBQdKKZ9jeugs+HiqO5HormU= honnef.co/go/[email protected] h1:oFEHCKeID7to/3autwsWfnuv69j3NsfcXbvJKuIcep8= mvdan.cc/[email protected] h1:G3QvahNDmpD+Aek/bNOLrFR2XC6ZAdo62dZu65gmwGo= mvdan.cc/xurls/[email protected] h1:lyBNOm8Wo71UknhUs4QTFUNNMyxy2JEIaKKo0RWOh+8= go: go1.22.0

go env

GO111MODULE=''
GOARCH='arm64'
GOBIN=''
GOCACHE='/Users/stephen/Library/Caches/go-build'
GOENV='/Users/stephen/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMODCACHE='/Users/stephen/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Users/stephen/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/Users/stephen/go/pkg/mod/golang.org/[email protected]'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='go1.22.0+auto'
GOTOOLDIR='/Users/stephen/go/pkg/mod/golang.org/[email protected]/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='go1.22.0'
GCCGO='gccgo'
AR='ar'
CC='clang'
CXX='clang++'
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 -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/9d/1smj789x4r5bdjccy3tqss0c0000gn/T/go-build1153037537=/tmp/go-build -gno-record-gcc-switches -fno-common'

What did you do?

https://go.dev/play/p/rMbWTBEtveQ

What did you see happen?

gopls indicates an error even if it should be considered valid when GOEXPERIMENT=rangefunc is set

What did you expect to see?

No error shown

Editor and settings

Neovim with the following gopls configuration

            lspconfig.gopls.setup({
                capabilities = addCmpCapabilities(lspconfig.gopls.capabilities),
                settings = {
                    gopls = {
                        allowModfileModifications = false,
                        gofumpt = true,
                        codelenses = {
                            generate = true,
                            tidy = true,
                            upgrade_dependency = true,
                            vendor = true,
                        },
                        buildFlags = { "-tags", "goexperiment.rangefunc" },
                        directoryFilters = { "-**/node_modules", "-**/.git" },
                    },
                },
            })

Logs

No response

[findleyr]

It works for me.

In your go env output, I see GOEXPERIMENT=''. Are you sure you set GOEXPERIMENT in your environment?

I just did:

export GOEXPERIMENT=rangefunc
nvim main.go

I'm using coc.nvim, but wouldn't expect neovim native LSP to behave differently.

[stephenafamo]

When I try to set it as environment variables, I get

go: unknown GOEXPERIMENT rangefunc

I had previously tried to use the environment variable to add the configuration of gopls and got the same error, but I thought that was an issue with how I was setting up the configuration.

I have tried it again, but I run into the same error:

            lspconfig.gopls.setup({
                capabilities = addCmpCapabilities(lspconfig.gopls.capabilities),
                settings = {
                    gopls = {
                        allowModfileModifications = false,
                        gofumpt = true,
                        codelenses = {
                            generate = true,
                            tidy = true,
                            upgrade_dependency = true,
                            vendor = true,
                        },
                        buildFlags = { "-tags", "goexperiment.rangefunc" },
                        directoryFilters = { "-**/node_modules", "-**/.git" },
                        env = {
                            GOEXPERIMENT = "rangefunc",
                        },
                    },
                },
            })

[findleyr]

go: unknown GOEXPERIMENT rangefunc

Hmm, do you have multiple versions of go installed? Is it possible that the go your neovim sees is not go 1.22?

[stephenafamo]

So I updated my go binary (not just the toolchain) to go1.22 and got rid of the error:

go: unknown GOEXPERIMENT rangefunc

However, the InvalidRangeExpr error is still reported despite adding GOEXPERIMENT=rangefunc to everywhere I could:

• go env with go env -w GOEXPERIMENT=rangefunc
• The local project env with .envrc
• The gopls configuration as outlined above.

[findleyr]

Could you share gopls logs from a short session that demonstrates the problem? That would help us investigate why it isn't working in your session. https://github.com/golang/tools/blob/master/gopls/doc/troubleshooting.md#capture-logs

[stephenafamo]

My bad. I was using Mason on Neovim, which installs its own gopls which is at v14.2, when I force it to use my installed gopls v15.0-pre.3, I was able to get it to work, but only with a local env variable

• Setting go env with go env -w GOEXPERIMENT=rangefunc did not work
• Setting the go pls configurations (both env and buildFlags also did not work.

[RunThem]

@stephenafamo hi, did you solve this problem?

[alassek]

@RunThem The solution is to update gopls in Mason:

:MasonInstall gopls