cmd/go: go test -race -coverpkg=all AST-parser is broken

[xaionaro]

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

$ go version
go version go1.20.4 linux/amd64

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="/home/xaionaro/.cache/go-build"
GOENV="/home/xaionaro/.config/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/home/xaionaro/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/xaionaro/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/xaionaro/.gimme/versions/go1.20.4.linux.amd64"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/xaionaro/.gimme/versions/go1.20.4.linux.amd64/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="go1.20.4"
GCCGO="gccgo"
GOAMD64="v1"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/xaionaro/go/src/github.com/linuxboot/contest/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-build143176400=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Just run:

cd /tmp
git clone https://github.com/leodido/go-urn
cd go-urn
go test -race -coverpkg=all ./

What did you expect to see?

ok  	github.com/leodido/go-urn	0.049s	coverage: 7.8% of statements in all

What did you see instead?

../../../../pkg/mod/github.com/leodido/[email protected]/urn.go:86:2: syntax error: unexpected var after top level declaration

[xaionaro]

The problem is not reproducible in Go1.18.

[seankhliao]

fixed on tip.

[cristaloleg]

Fixed in #58370