String cleanupSource(String source) {
if (source.isEmpty()) {
return source.concat("\n");
}
int lastChIdx = source.length() - 1;
if (source.charAt(lastChIdx) != '\n') {
// Append a newline at the end
source = source.concat("\n");
} else {
// Remove all newlines at the end but one
while (lastChIdx >= 1) {
Character ch1 = source.charAt(lastChIdx);
if (ch1 == '\n' || Character.isWhitespace(ch1)) {
source = source.substring(0, lastChIdx--);
} else {
break;
}
}
source = source.concat("\n");
}
return source;
}
