sanitzeForEncoding method
Sanitizes the source
by removing/replacing any values that can't show up.
Implementation
@override
String sanitzeForEncoding(String source) {
for (var i = 0; i < source.length; i++) {
if (charMap.containsKey(source[i])) {
continue;
}
final value = mapInvalidCharacter(source[i]);
source = source.replaceRange(i, i + 1, value);
i += value.length - 1;
}
return source;
}