scanner: make Scanner.peek_token more robust (p.peek_token(-999999) will return an EOF token, instead of garbage data)

spytheman · spytheman · commit fdbd40d806a1 · 2022-11-27T12:09:43.000+02:00
diff --git a/vlib/v/scanner/scanner.v b/vlib/v/scanner/scanner.v
@@ -605,7 +605,7 @@ pub fn (mut s Scanner) scan() token.Token {
 [direct_array_access; inline]
 pub fn (s &Scanner) peek_token(n int) token.Token {
 	idx := s.tidx + n
-	if idx >= s.all_tokens.len {
+	if idx >= s.all_tokens.len || idx < 0 {
 		return s.new_eof_token()
 	}
 	t := s.all_tokens[idx]

Original file line number	Diff line number	Diff line change
`@@ -605,7 +605,7 @@ pub fn (mut s Scanner) scan() token.Token {`
`605`	`605`	`[direct_array_access; inline]`
`606`	`606`	`pub fn (s &Scanner) peek_token(n int) token.Token {`
`607`	`607`	`idx := s.tidx + n`
`608`		`- if idx >= s.all_tokens.len {`
	`608`	`+ if idx >= s.all_tokens.len \|\| idx < 0 {`
`609`	`609`	`return s.new_eof_token()`
`610`	`610`	`}`
`611`	`611`	`t := s.all_tokens[idx]`