extract_function_range_integer.txtar

# Extract a named integer range and verify nonpositive bounds, typed values, and expression evaluation.
exec semedit refactor-extract-callable --file service.go --symbol visitRange --in-function Run --kind function --start-line 8 --end-line 10
stdout 'symbol: visitRange'
cmp service.go want/service.go
exec go test ./...

-- go.mod --
module example.com/extractrangeinteger

go 1.23
-- service.go --
package sample

type Count int

var visited []Count

func Run(limit Count) {
	for index := range limit + 1 {
		record(index)
	}
}

func record(value Count) { visited = append(visited, value) }
-- service_test.go --
package sample

import (
	"reflect"
	"testing"
)

func TestRunPreservesIntegerRangeSemantics(t *testing.T) {
	for _, test := range []struct {
		limit Count
		want  []Count
	}{
		{limit: -2, want: nil},
		{limit: -1, want: nil},
		{limit: 0, want: []Count{0}},
		{limit: 2, want: []Count{0, 1, 2}},
	} {
		visited = nil
		Run(test.limit)
		if !reflect.DeepEqual(visited, test.want) {
			t.Fatalf("Run(%d) visited = %v, want %v", test.limit, visited, test.want)
		}
	}
}
-- want/service.go --
package sample

type Count int

var visited []Count

func Run(limit Count) {
	visitRange(limit)
}

func visitRange(limit Count) {
	for index := range limit + 1 {
		record(index)
	}
}

func record(value Count) { visited = append(visited, value) }