go/src/go/printer/gobuild.go

func (p *printer) fixGoBuildLines() { … }

// appendLines is like append(x, y...)
// but it avoids creating doubled blank lines,
// which would not be gofmt-standard output.
// It assumes that only whole blocks of lines are being appended,
// not line fragments.
func appendLines(x, y []byte) []byte { … }

func (p *printer) lineAt(start int) []byte { … }

func (p *printer) commentTextAt(start int) string { … }

func isNL(b byte) bool { … }