Improve number parsing in JSON handling

Refactor number parsing to differentiate between integers and floats to match the behaviour of the stringify method.

Author: Chkoupinator

core/io/json.cpp

@@ -384,11 +384,26 @@ Error JSON::_get_token(const char32_t *p_str, int &index, int p_len, Token &r_to
 
 				if (p_str[index] == '-' || is_digit(p_str[index])) {
 					//a number
-					const char32_t *rptr;
-					double number = String::to_float(&p_str[index], &rptr);
-					index += (rptr - &p_str[index]);
-					r_token.type = TK_NUMBER;
-					r_token.value = number;
+					int sub_index = index;
+					while (is_digit(p_str[sub_index])) {
+						sub_index++;
+					}
+
+					if (p_str[sub_index] == 'e' || p_str[sub_index] == 'E' || p_str[sub_index] == '.') {
+						// float detected
+						const char32_t *rptr;
+						const double number = String::to_float(&p_str[index], &rptr);
+						index += (rptr - &p_str[index]);
+						r_token.type = TK_NUMBER;
+						r_token.value = number;
+					} else {
+						// int detected
+						--sub_index;
+						const int64_t number = String::to_int(&p_str[index], sub_index - index);
+						index = sub_index;
+						r_token.type = TK_NUMBER;
+						r_token.value = number;
+					}
 					return OK;
 
 				} else if (is_ascii_alphabet_char(p_str[index])) {