# When GOPROXY=off, fetching modules not matched by GONOPROXY fails.
env GONOPROXY=*/fortune
env GOPROXY=off
! go get golang.org/x/text
stderr '^go: golang.org/x/text: module lookup disabled by GOPROXY=off$'

# GONOPROXY bypasses proxy
[!net:rsc.io] skip
[!git] skip
env GOPRIVATE=none
env GONOPROXY='*/fortune'
! go get rsc.io/fortune # does not exist in real world, only on test proxy

env GO111MODULE=on
env sumdb=$GOSUMDB
env proxy=$GOPROXY
env GOPROXY GONOPROXY GOSUMDB GONOSUMDB

# rejected proxy fails verification
cp go.mod.orig go.mod
rm go.sum
env GOPROXY=$proxy/sumdb-503
! go get rsc.io/quote
stderr 503

# fetch through working proxy is OK
cp go.mod.orig go.mod
rm go.sum
env GOPROXY=$proxy
go get rsc.io/quote

# repeated fetch works entirely from cache, does not consult sumdb
cp go.mod.orig go.mod

	GOARCH
	GOARM
	GOARM64
	GOBIN
	GOCACHE
	GOCACHEPROG
	GOENV
	GOEXE
	GOEXPERIMENT
	GOFLAGS
	GOGCCFLAGS
	GOHOSTARCH
	GOHOSTOS
	GOINSECURE
	GOMIPS
	GOMIPS64
	GOMODCACHE
	GONOPROXY
	GONOSUMDB
	GOOS
	GOPATH
	GOPPC64
	GOPRIVATE
	GOPROXY
	GORISCV64
	GOROOT
	GOSUMDB
	GOTMPDIR
	GOTOOLCHAIN
	GOTOOLDIR
	GOVCS
	GOWASM
	GOWORK
	GO_EXTLINK_ENABLED
	PKG_CONFIG

        GOEXE=""
        GOEXPERIMENT=""
        GOFLAGS=""
        GOHOSTARCH="arm64"
        GOHOSTOS="darwin"
        GOINSECURE=""
        GOMODCACHE="/Users/gopher/go/pkg/mod"
        GONOPROXY=""
        GONOSUMDB=""
        GOOS="darwin"
        GOPATH="/Users/gopher/go"
        GOPRIVATE=""
        GOPROXY="https://proxy.golang.org,direct"
        GOROOT="/usr/local/go"
        GOSUMDB="sum.golang.org"

env GO111MODULE=on
env sumdb=$GOSUMDB
env proxy=$GOPROXY
env GOPROXY GONOPROXY GOSUMDB GONOSUMDB
env dbname=localhost.localdev/sumdb

# disagreeing with the sumdb produces security errors
# (this also populates tiles on the sumdb server).
cp go.mod.orig go.mod
env GOSUMDB=$sumdb' '$proxy/sumdb-wrong
! go get rsc.io/quote
stderr 'go: rsc.io/quote@v1.5.2: verifying module: checksum mismatch'
stderr 'downloaded: h1:3fEy'

var (
	errProxyOff       = notExistErrorf("module lookup disabled by GOPROXY=off")
	errNoproxy  error = notExistErrorf("disabled by GOPRIVATE/GONOPROXY")
	errUseProxy error = notExistErrorf("path does not match GOPRIVATE/GONOPROXY")
)

func lookupDirect(ctx context.Context, path string) (Repo, error) {
	security := web.SecureOnly

	if module.MatchPrefixPatterns(cfg.GOINSECURE, path) {

env GO111MODULE=on
env sumdb=$GOSUMDB
env proxy=$GOPROXY
env GOPROXY GONOPROXY GOSUMDB GONOSUMDB

# basic fetch (through proxy) works
cp go.mod.orig go.mod
go get rsc.io/fortune@v1.0.0 # note: must use test proxy, does not exist in real world
rm $GOPATH/pkg/mod/cache/download/sumdb # rm sumdb cache but NOT package download cache
rm go.sum

# can fetch by explicit URL
cp go.mod.orig go.mod
env GOSUMDB=$sumdb' '$proxy/sumdb-direct

	// equivalent to os.ErrNotFound, which is true for 404 and 410 responses.
	fallBackOnError bool
}

func proxyList() ([]proxySpec, error) {
	proxyOnce.Do(func() {
		if cfg.GONOPROXY != "" && cfg.GOPROXY != "direct" {
			proxyOnce.list = append(proxyOnce.list, proxySpec{url: "noproxy"})
		}

		goproxy := cfg.GOPROXY
		for goproxy != "" {
			var url string
			fallBackOnError := false

	GOPROXY, GOPROXYChanged     = EnvOrAndChanged("GOPROXY", "")
	GOSUMDB, GOSUMDBChanged     = EnvOrAndChanged("GOSUMDB", "")
	GOPRIVATE                   = Getenv("GOPRIVATE")
	GONOPROXY, GONOPROXYChanged = EnvOrAndChanged("GONOPROXY", GOPRIVATE)
	GONOSUMDB, GONOSUMDBChanged = EnvOrAndChanged("GONOSUMDB", GOPRIVATE)
	GOINSECURE                  = Getenv("GOINSECURE")
	GOVCS                       = Getenv("GOVCS")
)

		{Name: "GOHOSTOS", Value: runtime.GOOS},
		{Name: "GOINSECURE", Value: cfg.GOINSECURE},
		{Name: "GOMODCACHE", Value: cfg.GOMODCACHE, Changed: cfg.GOMODCACHEChanged},
		{Name: "GONOPROXY", Value: cfg.GONOPROXY, Changed: cfg.GONOPROXYChanged},
		{Name: "GONOSUMDB", Value: cfg.GONOSUMDB, Changed: cfg.GONOSUMDBChanged},
		{Name: "GOOS", Value: cfg.Goos, Changed: cfg.Goos != runtime.GOOS},