Fix: NewGRF string interpolation did not process all string parameters, if certain string control codes were present.

String control codes with inline data may contain null characters, in particular plural/gender/case choice lists.

src/newgrf_text.cpp

@@ -764,6 +764,40 @@ static void ProcessNewGRFStringControlCode(char32_t scc, const char *&str, TextR
 	 * After this call, a new call is made with `modify_parameters` set to false when the string is finally formatted. */
 	switch (scc) {
 		default: return;
+
+		case SCC_PLURAL_LIST:
+			++str; // plural form
+			[[fallthrough]];
+		case SCC_GENDER_LIST: {
+			++str; // offset
+			/* plural and gender choices cannot contain any string commands, so just skip the whole thing */
+			uint num = static_cast<uint8_t>(*str++);
+			uint total_len = 0;
+			for (uint i = 0; i != num; i++) {
+				total_len += static_cast<uint8_t>(*str++);
+			}
+			str += total_len;
+			break;
+		}
+
+		case SCC_SWITCH_CASE: {
+			/* skip all cases and continue with default case */
+			uint num = static_cast<uint8_t>(*str++);
+			for (uint i = 0; i != num; i++) {
+				str += 3 + (static_cast<uint8_t>(str[1]) << 8) + static_cast<uint8_t>(str[2]);
+			}
+			break;
+		}
+
+		case SCC_GENDER_INDEX:
+		case SCC_SET_CASE:
+			++str;
+			break;
+
+		case SCC_ARG_INDEX:
+			NOT_REACHED();
+			break;
+
 		case SCC_NEWGRF_PRINT_BYTE_SIGNED:      params.emplace_back(stack.PopSignedByte());    break;
 		case SCC_NEWGRF_PRINT_QWORD_CURRENCY:   params.emplace_back(stack.PopSignedQWord());   break;