cmd/go: work use does nothing when not in workspace root

[seankhliao]

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

$ go version
go version go1.18beta2 linux/amd64
go version devel go1.18-5fd8c9b5c5 Sat Jan 29 03:53:30 2022 +0000 linux/amd64

Does this issue reproduce with the latest release?

prerelease

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

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/arccy/.cache/go-build"
GOENV="/home/arccy/.config/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/home/arccy/.data/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/arccy/.data/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/arccy/sdk/gotip"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/arccy/sdk/gotip/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="devel go1.18-5fd8c9b5c5 Sat Jan 29 03:53:30 2022 +0000"
GCCGO="gccgo"
GOAMD64="v1"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/arccy/tmp/testrepo-771/go.mod"
GOWORK="/home/arccy/tmp/testrepo-771/go.work"
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-build4285625585=/tmp/go-build -gno-record-gcc-switches"

What did you do?

$ mkdir example && cd example               
$ go mod init example                               
$ go work init       
$ mkdir bar && cd bar        
$ go mod init example/bar       
$ go work use . 
$ cat ../go.work
go 1.18

What did you expect to see?

Either use bar added to go.work or an error

What did you see instead?

no entry added, no error reported

cc @bcmills @matloob

[gopherbot]

Change https://golang.org/cl/382240 mentions this issue: cmd/go: fix relative-path normalization in go.work files

[bcmills]

Thanks for the report! go work use is new in 1.18 and this is a pretty severe bug in it, so marking as release-blocker (and I've just mailed out what I believe is the fix).