! go mod tidy
stderr '^go: warning: ignoring go.mod in \$GOPATH'
stderr '^go: go.mod file not found in current directory or any parent directory; see ''go help modules'''

go env
stdout 'GOPATH='
stderr '^go: warning: ignoring go.mod in \$GOPATH'

-- $GOPATH/go.mod --
module bug

	os.Exit(testMain(m))
}

func testMain(m *testing.M) int {
	GOPATH, err := os.MkdirTemp("", "cgolife")
	if err != nil {
		log.Panic(err)
	}
	defer os.RemoveAll(GOPATH)
	os.Setenv("GOPATH", GOPATH)

	// Copy testdata into GOPATH/src/cgolife, along with a go.mod file
	// declaring the same path.
	modRoot := filepath.Join(GOPATH, "src", "cgolife")
	if err := cgotest.OverlayDir(modRoot, "testdata"); err != nil {

# go env GOMOD should not trigger a toolchain download
cd $GOPATH/mod
go env GOMOD
stdout mod[/\\]go.mod
! stderr 'go: toolchain go1.500 invoked to provide go1.700'

# go env GOWORK should not trigger a toolchain download
cd $GOPATH/work
go env GOWORK
stdout work[/\\]go.work
! stderr 'go: toolchain go1.500 invoked to provide go1.700'

-- $GOPATH/mod/go.mod --
module example.com

go 1.700

# Verifies golang.org/issue/51589

# download the modules first
env GO111MODULE=on
env GOPATH=$WORK/gopath
cd $WORK/x
go mod tidy

# Use download cache as file:/// proxy.
[GOOS:windows] env GOPROXY=file:///$WORK/gopath/pkg/mod/cache/download
[!GOOS:windows] env GOPROXY=file://$WORK/gopath/pkg/mod/cache/download
rm $WORK/gopath/pkg/mod/cache/download/golang.org/x/text/
go mod tidy -e

exists $GOPATH/pkg/sumdb
! exists $WORK/modcache/sumdb
exists $WORK/modcache/cache/download/sumdb

# Test that the default GOMODCACHE is $GOPATH[0]/pkg/mod
env GOMODCACHE=
go env GOMODCACHE
stdout $GOPATH[/\\]pkg[/\\]mod
go get rsc.io/quote@v1.0.0
exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.0.0.info

stderr 'checksum mismatch'
! exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.1.0.zip

# With good go.sum, sync works.
rm go.sum
cp go.sum.good go.sum
go mod tidy
exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.1.0.zip
exists $GOPATH/pkg/mod/rsc.io/quote@v1.1.0/quote.go

# go.sum should have the new checksum for go.mod
grep '^rsc.io/quote v1.1.0/go.mod ' go.sum

# verify should work
go mod verify

go list -f '{{.Dir}}' example.com/q
stdout $GOPATH[\\/]src[\\/]vendor[\\/]example.com[\\/]q
go list -f '{{.Dir}}' example.com/b
stdout $GOPATH[\\/]src[\\/]vendor[\\/]example.com[\\/]b
go list -f '{{.Dir}}' example.com/w
stdout $GOPATH[\\/]src[\\/]vendor[\\/]example.com[\\/]w
go list -f '{{.Dir}}' example.com/z
stdout $GOPATH[\\/]src[\\/]vendor[\\/]example.com[\\/]z

cmp $GOPATH/src/vendor/example.com/q/q.go q1_1_0/q.go

package t

-- $GOPATH/src/github.com/rsc/go-get-issue-11864/tx/tx_test.go --
package tx_test

import _ "vendor.org/p"
import _ "vendor.org/p1"
import "testing"

func TestNop(t *testing.T) {}

-- $GOPATH/src/github.com/rsc/go-get-issue-11864/tx/tx.go --
package tx

-- $GOPATH/src/github.com/rsc/go-get-issue-11864/vendor/vendor.org/p1/p1.go --
package p1 // import "vendor.org/p1"

# GO111MODULE=off
env GO111MODULE=off
! exec $WORK/testimport$GOEXE gobuild.example.com/x/y/z/w .

# GO111MODULE=auto in GOPATH/src
env GO111MODULE=auto
exec $WORK/testimport$GOEXE gobuild.example.com/x/y/z/w .

# GO111MODULE=auto outside GOPATH/src
cd $GOPATH/other
env GO111MODULE=auto
exec $WORK/testimport$GOEXE other/x/y/z/w .
stdout w2.go

! exec $WORK/testimport$GOEXE gobuild.example.com/x/y/z/w .

# Test overlays that affect go.mod files

# The go.mod file can exist only in the overlay.
cd $WORK/gopath/src/no-go-mod
go list -overlay overlay.json .
stdout example.com/simple

# Check content of overlaid go.mod is used.
cd $WORK/gopath/src/overlay-go-mod
go list -overlay overlay.json .
stdout use.this/module/name

# Check content of overlaid go.mod in a replacement module is used.
# The go.mod in the replacement module is missing a requirement