Function StrMakeValid

src/string.cpp:119–148

 */
template <class Builder>
static void StrMakeValid(Builder &builder, StringConsumer &consumer, StringValidationSettings settings)
{
	/* Assume the ABSOLUTE WORST to be in str as it comes from the outside. */
	while (consumer.AnyBytesLeft()) {
		auto c = consumer.TryReadUtf8();
		if (!c.has_value()) {
			/* Maybe the next byte is still a valid character? */
			consumer.Skip(1);
			continue;
		}
		if (*c == 0) break;

		if ((IsPrintable(*c) && (*c < SCC_SPRITE_START || *c > SCC_SPRITE_END)) ||
				(settings.Test(StringValidationSetting::AllowControlCode) && IsSccEncodedCode(*c)) ||
				(settings.Test(StringValidationSetting::AllowNewline) && *c == '\n')) {
			builder.PutUtf8(*c);
		} else if (settings.Test(StringValidationSetting::AllowNewline) && *c == '\r' && consumer.PeekCharIf('\n')) {
			/* Skip \r, if followed by \n */
			/* continue */
		} else if (settings.Test(StringValidationSetting::ReplaceTabCrNlWithSpace) && (*c == '\r' || *c == '\n' || *c == '\t')) {
			/* Replace the tab, carriage return or newline with a space. */
			builder.PutChar(' ');
		} else if (settings.Test(StringValidationSetting::ReplaceWithQuestionMark)) {
			/* Replace the undesirable character with a question mark */
			builder.PutChar('?');
		}
	}

	/* String termination, if needed, is left to the caller of this function. */
}

/**
 * Scans the string for invalid characters and replaces them with a