Skip to content

x/tools/gopls: S1030 is misleading and should not be there #74575

Closed as not planned
@oakad

Description

@oakad

gopls version

Build info

golang.org/x/tools/gopls v0.19.1
golang.org/x/tools/gopls@v0.19.1 h1:Yodhp3rnpnag60lVZrYPYbGMxTlTCIAj/B2Rv7AKuhA=
github.com/BurntSushi/toml@v1.4.1-0.20240526193622-a339e1f7089c h1:pxW6RcqyfI9/kWtOwnv/G+AzdKuy2ZrqINhenH4HyNs=
github.com/fatih/camelcase@v1.0.0 h1:hxNvNX/xYBp0ovncs8WyWZrOrpBNub/JfaMvbURyft8=
github.com/fatih/gomodifytags@v1.17.1-0.20250423142747-f3939df9aa3c h1:dDSgAjoOMp8da3egfz0t2S+t8RGOpEmEXZubcGuc0Bg=
github.com/fatih/structtag@v1.2.0 h1:/OdNE99OxoI/PqaW/SuSK9uxxT3f/tcSZgon/ssNSx4=
github.com/google/go-cmp@v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
golang.org/x/exp/typeparams@v0.0.0-20250218142911-aa4b98e5adaa h1:Br3+0EZZohShrmVVc85znGpxw7Ca8hsUJlrdT/JQGw8=
golang.org/x/mod@v0.25.0 h1:n7a+ZbQKQA/Ysbyb0/6IbB1H/X41mKgbhfv7AfG/44w=
golang.org/x/sync@v0.15.0 h1:KWH3jNZsfyT6xfAfKiz6MRNmd46ByHDYaZ7KSkCtdW8=
golang.org/x/telemetry@v0.0.0-20250417124945-06ef541f3fa3 h1:RXY2+rSHXvxO2Y+gKrPjYVaEoGOqh3VEXFhnWAt1Irg=
golang.org/x/text@v0.26.0 h1:P42AVeLghgTYr4+xUnTRKDMqpar+PtX7KWuNQL21L8M=
golang.org/x/tools@v0.34.1-0.20250610205101-c26dd3ba555e h1:XnjOegqwH6kBJoae6InSGbIFPHcLtUT/Eq8HjrZKbmQ=
golang.org/x/vuln@v1.1.4 h1:Ju8QsuyhX3Hk8ma3CesTbO8vfJD9EvUBgHvkxHBzj0I=
honnef.co/go/tools@v0.7.0-0.dev.0.20250523013057-bbc2f4dd71ea h1:fj8r9irJSpolAGUdZBxJIRY3lLc4jH2Dt4lwnWyWwpw=
mvdan.cc/gofumpt@v0.7.0 h1:bg91ttqXmi9y2xawvkuMXyvAA/1ZGJqYAEGjXuP0JXU=
mvdan.cc/xurls/v2@v2.6.0 h1:3NTZpeTxYVWNSokW3MKeyVkz/j7uYXYiMtXRUfmjbgI=
go: go1.24.3

go env

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/oakad/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/home/oakad/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build466808813=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/home/oakad/go/pkg/mod'
GOOS='linux'
GOPATH='/home/oakad/go'
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/lib/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/home/oakad/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/lib/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.24.3'
GOWORK=''
PKG_CONFIG='pkg-config'

What did you do?

S1030 warning is misleading and either should not be there or Buffer.String() needs to be altered (though, the later is unlikely, so first option).

The Buffer.String method is implemented as following:

func (b *Buffer) String() string {
	if b == nil {
		// Special case, useful in debugging.
		return "<nil>"
	}
	return string(b.buf[b.off:])
}

However, in vast majority of practical applications of buffer content being converted to string (usually as a result of some encoding operation that took place) the user never expects to see the ostensibly helpful string "<nil>". If the buffer is empty, the expectation is always "", empty string.

A typical program logic usually goes as "some data in" -> "nothing was encoded for whatever reason" -> "outcome is empty string for which there's a check".

Also, compare with strings.Builder.String().

What did you see happen?

S1030 warning is raised when I use string(b.Bytes()).

What did you expect to see?

Don't expect to see S1030 warning. :-)

Editor and settings

No response

Logs

No response

Metadata

Metadata

Assignees

No one assigned

    Labels

    ToolProposalIssues describing a requested change to a Go tool or command-line program.ToolsThis label describes issues relating to any tools in the x/tools repository.goplsIssues related to the Go language server, gopls.

    Type

    No type

    Projects

    No projects

    Milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions