This test verifies the fix for golang/go#44813: extraction failure when there
are blank identifiers.

-- go.mod --
module mod.test/extract

go 1.18

-- p.go --
package extract

import "fmt"

func main() {
	x := []rune{} //@codeaction("x", end, "refactor.extract.function", ext)
	s := "HELLO"
	for _, c := range s {
		x = append(x, c)
	} //@loc(end, "}")
	fmt.Printf("%x\n", x)
}

-- @ext/p.go --
package extract

import "fmt"

func main() {
	//@codeaction("x", end, "refactor.extract.function", ext)
	x := newFunction() //@loc(end, "}")
	fmt.Printf("%x\n", x)
}

func newFunction() []rune {
	x := []rune{}
	s := "HELLO"
	for _, c := range s {
		x = append(x, c)
	}
	return x
}