diff options
Diffstat (limited to 'internal/config/print.go')
| -rw-r--r-- | internal/config/print.go | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/internal/config/print.go b/internal/config/print.go index 5c3d467..a2244d0 100644 --- a/internal/config/print.go +++ b/internal/config/print.go @@ -3,6 +3,7 @@ package config import ( + "fmt" "strings" "krino/internal/sexp" @@ -59,12 +60,17 @@ func PrintExclude(x *Exclude) string { // Splice replaces the bytes of the form between start and end - a form's // Pos and End - with text, and returns the new file contents. Every other -// byte of src, comments and layout included, is kept exactly. -func Splice(src []byte, start, end sexp.Pos, text string) []byte { +// byte of src, comments and layout included, is kept exactly. Offsets that +// do not belong to src - a form parsed from text that has since changed - +// are an error, not a panic (plan 13 review F6). +func Splice(src []byte, start, end sexp.Pos, text string) ([]byte, error) { + if start.Offset < 0 || end.Offset < start.Offset || end.Offset > len(src) { + return nil, fmt.Errorf("config: splice %d:%d is not inside %d bytes", start.Offset, end.Offset, len(src)) + } out := make([]byte, 0, len(src)-(end.Offset-start.Offset)+len(text)) out = append(out, src[:start.Offset]...) out = append(out, text...) - return append(out, src[end.Offset:]...) + return append(out, src[end.Offset:]...), nil } // printAction renders one action form. |