# Test support for go mod edit -toolchain to set toolchain to use

env GOTOOLCHAIN=local
env GO111MODULE=on

! grep toolchain go.mod
go mod edit -toolchain=go1.9
grep 'toolchain go1.9' go.mod

go mod edit -toolchain=default
grep 'toolchain default' go.mod

go mod edit -toolchain=none
! grep toolchain go.mod

-- go.mod --
module m

# go get should update the go and toolchain lines in go.work
env TESTGO_VERSION=go1.21
env TESTGO_VERSION_SWITCH=switch
env GOTOOLCHAIN=auto
cp go.mod.new go.mod
cp go.work.new go.work
go get rsc.io/needgo121 rsc.io/needgo122 rsc.io/needgo123 rsc.io/needall
stderr '^go: rsc.io/needall@v0.0.1 requires go >= 1.23; switching to go1.23.9$'
stderr '^go: added rsc.io/needall v0.0.1'
grep 'go 1.23$' go.mod
grep 'go 1.23$' go.work
grep 'toolchain go1.23.9' go.mod

	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

env GOTOOLCHAIN=auto
env TESTGO_VERSION=go1.21.1

# Basic switch should work.
env TESTGO_VERSION_SWITCH=switch
go version
stdout go1.21.99

# Toolchain target mismatch should be detected.
env TESTGO_VERSION_SWITCH=mismatch
! go version
stderr '^go: toolchain go1.21.1 invoked to provide go1.21.99$'

# Toolchain loop should be detected.
env TESTGO_VERSION_SWITCH=loop
! go version

# Go should refuse to build code that is too new according to go.mod.

# go.mod too new
env GOTOOLCHAIN=local
! go build .
stderr '^go: go.mod requires go >= 1.99999 \(running go 1\..+\)$'

# go.mod referenced from go.work too new
cp go.work.old go.work
! go build .
stderr '^go: module . listed in go.work file requires go >= 1.99999, but go.work lists go 1.10; to update it:\n\tgo work use$'

! go work sync

	}

	// If we're asking about "go" (not "toolchain"), pretend to have
	// all earlier Go versions available without network access:
	// we will provide those ourselves, at least in GOTOOLCHAIN=auto mode.
	if r.path == "go" && gover.Compare(v, gover.Local()) <= 0 {
		return &RevInfo{Version: prefix + v}, nil
	}

	// Similarly, if we're asking about *exactly* the current toolchain,