x/tools/gopls: inaccurate diagnostics after switching branches

[rohan-rayaraddi]

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.

  • 1.17.6

• Run gopls -v version to get version of Gopls from the VS Code integrated terminal.

  • gopls v0.8.2

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

  • 1.66.0

• Check your installed extensions to get the version of the VS Code Go extension

  • v0.32.0

• Run Ctrl+Shift+P (Cmd+Shift+P on Mac OS) > Go: Locate Configured Go Tools command.

  • Checking configured tools....
    GOBIN: undefined
    toolsGopath:
    gopath: /Users/rohan.rayaraddi/go
    GOROOT: /usr/local/go
    PATH: /usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/go/bin:/Users/rohan.rayaraddi/bin:/Users/rohan.rayaraddi/go/bin

  go: /usr/local/go/bin/go: go version go1.17.6 darwin/amd64

  go-outline: /Users/rohan.rayaraddi/go/bin/go-outline (version: unknown - )
  gotests: /Users/rohan.rayaraddi/go/bin/gotests (version: unknown - )
  gomodifytags: /Users/rohan.rayaraddi/go/bin/gomodifytags (version: unknown - )
  impl: /Users/rohan.rayaraddi/go/bin/impl (version: unknown - )
  goplay: /Users/rohan.rayaraddi/go/bin/goplay (version: unknown - )
  dlv: /Users/rohan.rayaraddi/go/bin/dlv (version: unknown - )
  staticcheck: /Users/rohan.rayaraddi/go/bin/staticcheck (version: unknown - )
  gopls: /Users/rohan.rayaraddi/go/bin/gopls (version: unknown - )

go env
Workspace Folder (nutanix-era-cloud-service): /Users/rohan.rayaraddi/nutanix-era-cloud-service
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/rohan.rayaraddi/Library/Caches/go-build"
GOENV="/Users/rohan.rayaraddi/Library/Application Support/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="/Users/rohan.rayaraddi/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/rohan.rayaraddi/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GOVCS=""
GOVERSION="go1.17.6"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/dev/null"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/9d/z94gzxxn5nl209kz5ylyp0s40000gp/T/go-build977718275=/tmp/go-build -gno-record-gcc-switches -fno-common"

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.

Describe the bug

Say file f1 has a struct MyStruct on branch main. f1 was renamed to f2 in branch feature and then you checkout main branch, main shows an error than Mystruct is declared twice in f1 and f2, when infact f2 does not exist in the main branch

Steps to reproduce the behavior:

described above
microsoft/vscode#147326

Screenshots or recordings

If applicable, add screenshots or recordings to help explain your problem.

[findleyr]

Hi, I'm not sure this is a bug. I only reproduce this issue when the file is open in the editor. For example, see the gif below:

The reason this causes a type-checking error is that gopls sees f1.go on disk, but also sees f2.go in the open buffer. VS Code indicates that f2.go has been deleted on disk by striking out the tab name, and the diagnostic goes away if I close the tab.

@rohan-rayaraddi is that consistent with what you observe? If so, what did you expect to happen?

[rohan-rayaraddi]

Hi, I believe this is true. But the type checker marks the error in both f1 and f2. I have not tried closing f2 explicitly before changing the branch. I notice the issue in file f1 but don't explicitly navigate to f2 to close it. Ideally, since f2 is not in the branch, the type checker should not be able to find it in its current scope.
I see in other editors like intellij, that it maintains a list of files open per branch, and when you switch the branch it opens or closes relevant files.

[findleyr]

Ideally, since f2 is not in the branch, the type checker should not be able to find it in its current scope.

gopls does not know about branches (nor should it), and so does not differentiate between a file created by switching branches and a file created by running a script. Fundamentally the editor is telling gopls that f2 is open, and so gopls must compute diagnostics assuming f2 still exists.

So this sounds like an editor feature to me (not gopls or vscode-go related). I thought that perhaps vs code supports this feature, and it looks like it might?
https://stackoverflow.com/questions/61298899/how-to-configure-vs-code-to-automatically-close-deleted-files-when-switching-bra

Closing this issue as there's nothing we can do on our end.