x/tools/gopls: Wrong completion for int * time.Duration

[tebeka]

What version of Go, VS Code & VS Code Go extension are you using?

Version Information

• Run go version to get version of Go from the VS Code integrated terminal.
  • go version go1.20.1 linux/amd64
• Run gopls -v version to get version of Gopls from the VS Code integrated terminal.

Build info
----------
golang.org/x/tools/gopls v0.11.0
    golang.org/x/tools/[email protected] h1:/nvKHdTtePQmrv9XN3gIUN9MOdUrKzO/dcqgbG6x8EY=
    github.com/BurntSushi/[email protected] h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
    github.com/google/[email protected] h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
    github.com/sergi/[email protected] h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0=
    golang.org/x/[email protected] h1:QfTh0HpN6hlw6D3vu8DAwC8pBIwikq0AI1evdm+FksE=
    golang.org/x/exp/[email protected] h1:fl8k2zg28yA23264d82M4dp+YlJ3ngDcpuB1bewkQi4=
    golang.org/x/[email protected] h1:LapD9S96VoQRhi/GrNTqeBJFrUjs5UHCAtTlgwA5oZA=
    golang.org/x/[email protected] h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
    golang.org/x/[email protected] h1:ljd4t30dBnAvMZaQCevtY0xLLD0A+bRZXbgLMLU1F/A=
    golang.org/x/[email protected] h1:BrVqGRd7+k1DiOgtnFvAkoQEWQvBc25ouMJM6429SFg=
    golang.org/x/[email protected] h1:7/HkGkN/2ktghBCSRRgp31wAww4syfsW52tj7yirjWk=
    golang.org/x/[email protected] h1:qptQiQwEpETwDiz85LKtChqif9xhVkAm8Nhxs0xnTww=
    honnef.co/go/[email protected] h1:oDx7VAwstgpYpb3wv0oxiZlxY+foCpRAwY7Vk6XpAgA=
    mvdan.cc/[email protected] h1:JVf4NN1mIpHogBj7ABpgOyZc65/UUOkKQFkoURsz4MM=
    mvdan.cc/xurls/[email protected] h1:tzxjVAj+wSBmDcF6zBB7/myTy3gX9xvi8Tyr28AuQgc=
go: go1.20.1

• Run code -v or code-insiders -v to get version of VS Code or VS Code Insiders.

1.76.0
92da9481c0904c6adfe372c12da3b7748d74bdcb
x64

• Check your installed extensions to get the version of the VS Code Go extension
  • v0.38.0
• Run Ctrl+Shift+P (Cmd+Shift+P on Mac OS) > Go: Locate Configured Go Tools command.

Checking configured tools....
GOBIN: undefined
toolsGopath: 
gopath: /home/miki/go
GOROOT: /home/miki/sdk/go1.20.1
PATH: /home/miki/bin:/home/miki/.local/bin:/home/miki/.venv/bin:/home/miki/sdk/go/bin:/home/miki/go/bin:/home/miki/.poetry/bin:/home/miki/.cargo/bin:/home/miki/.local/share/gem/ruby/3.0.0/bin:/home/miki/.local/bin:/opt/google-cloud-sdk/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/lib/jvm/default/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl:/var/lib/snapd/snap/bin:/home/miki/.fzf/bin

	go:	/home/miki/sdk/go/bin/go: go version go1.20.1 linux/amd64

	gotests:	/home/miki/go/bin/gotests	(version: v1.6.0 built with go: go1.20)
	gomodifytags:	/home/miki/go/bin/gomodifytags	(version: v1.16.0 built with go: go1.20.1)
	impl:	/home/miki/go/bin/impl	(version: v1.2.1-0.20221223162334-b4ecb144baaf built with go: go1.20.1)
	goplay:	/home/miki/go/bin/goplay	(version: v1.0.0 built with go: go1.20)
	dlv:	/home/miki/go/bin/dlv	(version: v1.20.1 built with go: go1.20.1)
	staticcheck:	/home/miki/go/bin/staticcheck	(version: v0.4.2 built with go: go1.20.1)
	gopls:	/home/miki/go/bin/gopls	(version: v0.11.0 built with go: go1.20.1)

go env
Workspace Folder (cache): /home/miki/work/lil/go-optimize/playground/cache
	GO111MODULE=""
	GOARCH="amd64"
	GOBIN=""
	GOCACHE="/home/miki/.cache/go-build"
	GOENV="/home/miki/.config/go/env"
	GOEXE=""
	GOEXPERIMENT=""
	GOFLAGS=""
	GOHOSTARCH="amd64"
	GOHOSTOS="linux"
	GOINSECURE=""
	GOMODCACHE="/home/miki/go/pkg/mod"
	GONOPROXY=""
	GONOSUMDB=""
	GOOS="linux"
	GOPATH="/home/miki/go"
	GOPRIVATE=""
	GOPROXY="https://proxy.golang.org,direct"
	GOROOT="/home/miki/sdk/go1.20.1"
	GOSUMDB="sum.golang.org"
	GOTMPDIR=""
	GOTOOLDIR="/home/miki/sdk/go1.20.1/pkg/tool/linux_amd64"
	GOVCS=""
	GOVERSION="go1.20.1"
	GCCGO="gccgo"
	GOAMD64="v1"
	AR="ar"
	CC="gcc"
	CXX="g++"
	CGO_ENABLED="1"
	GOMOD="/home/miki/work/lil/go-optimize/playground/go.mod"
	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 -fdebug-prefix-map=/tmp/go-build2080536578=/tmp/go-build -gno-record-gcc-switches"

Share the Go related settings you have added/edited

Run Preferences: Open Settings (JSON) command to open your settings.json file.
Share all the settings with the go. or ["go"] or gopls prefixes.

	"go.toolsManagement.autoUpdate": true,

Describe the bug

A clear and concise description of what the bug.
A clear and concise description of what you expected to happen.

When I have the following code:

n := 3
time.Sleep(n * time.Millisecond

And hit ENTER, the generated code is

n := 3
time.Sleep(n * int(time.Millisecond))

Which is wrong since time.Sleep expects a time.Duration.
The right code should be:

n := 3
time.Sleep(time.Duration(n) * time.Millisecond)

Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. See error

See above.

Screenshots or recordings

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[hyangah]

Thanks for the report. @tebeka
Wonder if this can be generalized beyond time.Duration. When we see two possible type conversions, decide the winner based on how the expression output is used. Transferring to the gopls issue tracker.

[muirdm]

The issue here is that n is of type int, which influences the expected type of time.Millisecond. If you accepted the completion for n initially, it would have inserted time.Duration(n), which would have kept things on the right track.

Perhaps special cases like this could be detected and completed as you suggest, but it doesn't seem possible in general.

[tebeka]

If you accepted the completion for n initially, it would have inserted time.Duration(n),

What does "accepted the completion for n initially" mean?

[muirdm]

What does "accepted the completion for n initially" mean?

It makes more sense with a longer variable like “fooBar := 3”. If you complete time.Sleep(foo it would insert fooBar wrapped in a type conversion.

[findleyr]

Thanks Muir -- I meant to comment the same.

I think this is working as intended.