toml.scanner: make end_of_text, at, next and peek return u32 (#13998)

vlib/toml/scanner/scanner.v

@@ -10,7 +10,7 @@ import toml.util
 
 pub const (
 	digit_extras = [`_`, `.`, `x`, `o`, `b`, `e`, `E`]
-	end_of_text  = -1
+	end_of_text  = math.max_u32
 )
 
 // Scanner contains the necessary fields for the state of the scan process.
@@ -263,7 +263,7 @@ pub fn (s &Scanner) remaining() int {
 // next returns the next character code from the input text.
 // next returns `end_of_text` if it can't reach the next character.
 [direct_array_access; inline]
-pub fn (mut s Scanner) next() int {
+pub fn (mut s Scanner) next() u32 {
 	if s.pos < s.text.len {
 		opos := s.pos
 		s.pos++
@@ -299,7 +299,7 @@ pub fn (mut s Scanner) skip_n(n int) {
 // at returns `end_of_text` if it can't get the current character.
 // unlike `next()`, `at()` does not change the state of the scanner.
 [direct_array_access; inline]
-pub fn (s &Scanner) at() int {
+pub fn (s &Scanner) at() u32 {
 	if s.pos < s.text.len {
 		return s.text[s.pos]
 	}
@@ -315,7 +315,7 @@ fn (s Scanner) at_crlf() bool {
 // peek returns the character code from the input text at position + `n`.
 // peek returns `end_of_text` if it can't peek `n` characters ahead.
 [direct_array_access; inline]
-pub fn (s &Scanner) peek(n int) int {
+pub fn (s &Scanner) peek(n int) u32 {
 	if s.pos + n < s.text.len {
 		// Allow peeking back - needed for spaces between date and time in RFC 3339 format :/
 		if n - 1 < 0 && s.pos + n - 1 >= 0 {

vlib/toml/scanner/scanner_test.v

@@ -25,9 +25,9 @@ fn test_next() {
 	assert s.next() == `a`
 	assert s.next() == `b`
 	assert s.next() == `c`
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
 }
 
 fn test_skip() {
@@ -35,14 +35,14 @@ fn test_skip() {
 	assert s.next() == `a`
 	s.skip()
 	assert s.next() == `c`
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
 }
 
 fn test_skip_n() {
 	mut s := scanner.new_scanner(input: scan_input) or { panic(err) }
 	s.skip_n(2)
 	assert s.next() == `c`
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
 }
 
 fn test_at() {
@@ -54,7 +54,7 @@ fn test_at() {
 	assert s.next() == `a`
 	assert s.next() == `b`
 	assert s.next() == `c`
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
 }
 
 fn test_peek() {
@@ -62,13 +62,13 @@ fn test_peek() {
 	assert s.peek(0) == `a`
 	assert s.peek(1) == `b`
 	assert s.peek(2) == `c`
-	assert s.peek(3) == -1
+	assert s.peek(3) == scanner.end_of_text
-	assert s.peek(4) == -1
+	assert s.peek(4) == scanner.end_of_text
 	//
 	assert s.next() == `a`
 	assert s.next() == `b`
 	assert s.next() == `c`
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
 }
 
 fn test_reset() {
@@ -76,7 +76,7 @@ fn test_reset() {
 	assert s.next() == `a`
 	s.next()
 	s.next()
-	assert s.next() == -1
+	assert s.next() == scanner.end_of_text
 	s.reset()
 	assert s.next() == `a`
 }