x/tools/gopls: limited cross references when using with vscode on Go repo

[thanm]

What version of Go are you using (go version)?

$ go version
$ go version
go version go1.15.2 linux/amd64
$ gopls version
golang.org/x/tools/gopls v0.5.0
    golang.org/x/tools/gopls@v0.5.0 h1:XEmO9RylgmaXp33iGrWfCGopVYDGBmLy+KmsIsfIo8Y=

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/usr/local/google/home/thanm/.cache/go-build"
GOENV="/usr/local/google/home/thanm/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/tmp/gopath/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/tmp/gopath"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/tmp/go.repo"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/tmp/go.repo/pkg/tool/linux_amd64"
GCCGO="/ssd/gcc-trunk/cross/bin/gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/tmp/go.repo/src/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build118750431=/tmp/go-build -gno-record-gcc-switches"

What did you do?

I am trying to use vscode to develop the Go standard library, as described in https://github.com/golang/vscode-go/blob/master/docs/stdlib.md. While I am able to get vscode up and running, I can't seem to get the correct set of cross references for exported package symbols.

I've attached a small shell script that checks out and builds Go stdlib and gopls, then invokes vscode in the proper spot. In the vscode session, I navigate to /src/cmd/internal/goobj2/objfile.go, then select the symbol PkgIdxSelf on line 142, and then select "Find All References".

What did you expect to see?

A similar operation using "guru" returns this set:

/tmp/go.repo/src/cmd/internal/goobj2/objfile.go:143.2-143.11: references to const PkgIdxSelf untyped int
/tmp/go.repo/src/cmd/internal/goobj/readnew.go:63.15-63.24: case goobj2.PkgIdxSelf:
/tmp/go.repo/src/cmd/internal/goobj/readnew.go:131.33-131.42: if a.Sym().PkgIdx != goobj2.PkgIdxSelf {
/tmp/go.repo/src/cmd/internal/obj/objfile2.go:336.56-336.65: case goobj2.PkgIdxNone, goobj2.PkgIdxBuiltin, goobj2.PkgIdxSelf: // not an external indexed reference
/tmp/go.repo/src/cmd/internal/obj/objfile2.go:437.19-437.28: PkgIdx: goobj2.PkgIdxSelf,
/tmp/go.repo/src/cmd/internal/obj/objfile2.go:452.22-452.31: s.PkgIdx = goobj2.PkgIdxSelf
/tmp/go.repo/src/cmd/internal/obj/sym.go:197.22-197.31: s.PkgIdx = goobj2.PkgIdxSelf
/tmp/go.repo/src/cmd/link/internal/loader/loader.go:600.14-600.23: case goobj2.PkgIdxSelf:
/tmp/go.repo/src/cmd/compile/internal/gc/iexport.go:1002.27-1002.36: if lsym.PkgIdx > goobj2.PkgIdxSelf || (lsym.PkgIdx == goobj2.PkgIdxInvalid && !lsym.Indexed()) || s.Linkname != "" {

What did you see instead?

Only returns references in the source file (objfile.go).

vscode-xref-repro-shellscript.txt

[heschik]

The problem here is that cmd is actually a separate module from the normal standard library, so you need to use src/cmd as the workspace folder in VS Code. That is, change the lastish line of the shell script from code . to code cmd.

Sorry for the trouble. We are actively working on multi-module workspaces, which we're expecting will get this working automatically.

[thanm]

Thanks Heschi -- makes sense. Appreciate the help; I'll close out the bug.

[dr2chase]

Does .vscode need to be moved into src/cmd also?

[heschik]

Yes.

[dr2chase]

and lo, it worked. Thanks.