Fix type checking and FRED help for containers in special argument lists (#4486)

Author: jg18

code/parse/sexp.cpp

@@ -2125,6 +2125,12 @@ int check_sexp_syntax(int node, int return_type, int recursive, int *bad_node, i
 
 		} else if (Sexp_nodes[node].subtype == SEXP_ATOM_CONTAINER_DATA) {
 			// this is an instance of "Replace Container Data"
+
+			// can't be used in special argument list
+			if (type == OPF_ANYTHING || type == OPF_DATA_OR_STR_CONTAINER) {
+				return SEXP_CHECK_TYPE_MISMATCH;
+			}
+
 			const int modifier_node = Sexp_nodes[node].first;
 			if (modifier_node == -1) {
 				return SEXP_CHECK_MISSING_CONTAINER_MODIFIER;
@@ -11029,6 +11035,13 @@ void sexp_change_argument_validity(int n, bool invalidate)
 		// first we must check if the arg_handler marks a selection. At the moment random-of is the only one that does this
 		arg_n = CDR(arg_handler);
 		while (invalidate && (arg_n != -1)) {
+			Assertion(Sexp_nodes[arg_n].subtype != SEXP_ATOM_CONTAINER_NAME,
+				"Attempt to use invalidate-argument with container %s. Please report!",
+				Sexp_nodes[arg_n].text);
+			Assertion(Sexp_nodes[arg_n].subtype != SEXP_ATOM_CONTAINER_DATA,
+				"Attempt to use invalidate-argument with data from container %s. Please report!",
+				Sexp_nodes[arg_n].text);
+
 			if (Sexp_nodes[arg_n].flags & SNF_ARGUMENT_SELECT) {
 				// now check if the selected argument matches the one we want to invalidate
 				if (!strcmp(CTEXT(n), CTEXT(arg_n))) {
@@ -11047,6 +11060,13 @@ void sexp_change_argument_validity(int n, bool invalidate)
 			arg_n = CDR(arg_handler);
 			while (arg_n != -1)
 			{
+				Assertion(Sexp_nodes[arg_n].subtype != SEXP_ATOM_CONTAINER_NAME,
+					"Attempt to change argument validity of container %s. Please report!",
+					Sexp_nodes[arg_n].text);
+				Assertion(Sexp_nodes[arg_n].subtype != SEXP_ATOM_CONTAINER_DATA,
+					"Attempt to change argument validity of data from container %s. Please report!",
+					Sexp_nodes[arg_n].text);
+
 				// match?
 				if (!strcmp(CTEXT(n), CTEXT(arg_n)))
 				{
@@ -33892,27 +33912,31 @@ SCP_vector<sexp_help_struct> Sexp_help = {
 	// Goober5000
 	{ OP_INVALIDATE_ARGUMENT, "Invalidate-argument (Conditional operator)\r\n"
 		"\tRemoves an argument from future consideration as a " SEXP_ARGUMENT_STRING " special data item.\r\n"
-		"\tFor argument-related SEXPs that accept containers as arguments, the retrieved arguments can't be individually invalidated.\r\n\r\n"
+		"\tFor argument-related SEXPs that accept containers as arguments, the retrieved arguments can't be individually invalidated.\r\n"
+		"\tAdditionally, you can't invalidate individual container arguments.\r\n\r\n"
 		"Takes 1 or more arguments...\r\n"
 		"\tAll:\tThe argument to remove from the preceding argument list." },
 
 	// Karajorma
 	{ OP_VALIDATE_ARGUMENT, "Validate-argument (Conditional operator)\r\n"
 		"\tRestores an argument for future consideration as a " SEXP_ARGUMENT_STRING " special data item.\r\n"
 		"\tIf the argument hasn't been previously invalidated, it will do nothing.\r\n"
-		"\tFor argument-related SEXPs that accept containers as arguments, the retrieved arguments can't be individually validated.\r\n\r\n"
+		"\tFor argument-related SEXPs that accept containers as arguments, the retrieved arguments can't be individually validated.\r\n"
+		"\tAdditionally, you can't validate individual container arguments.\r\n\r\n"
 		"Takes 1 or more arguments...\r\n"
 		"\tAll:\tThe argument to restore to the preceding argument list." },
 
 	// Karajorma
 	{ OP_INVALIDATE_ALL_ARGUMENTS, "Invalidate-all-arguments (Conditional operator)\r\n"
 		"\tRemoves all argument from future consideration as " SEXP_ARGUMENT_STRING " special data items.\r\n"
+		"\tFor argument-related SEXPs that accept containers as arguments, container arguments will also be invalidated, but they can't be indvidiually validated.\r\n\r\n"
 		"Takes no arguments." },
 
 	// Karajorma
 	{ OP_VALIDATE_ALL_ARGUMENTS, "Validate-all-arguments (Conditional operator)\r\n"
 		"\tRestores all arguments for future consideration as " SEXP_ARGUMENT_STRING " special data items.\r\n"
 		"\tIf the argument hasn't been previously invalidated, it will do nothing.\r\n"
+		"\tFor argument-related SEXPs that accept containers as arguments, container arguments will also be validated, but they can't be indvidiually invalidated.\r\n\r\n"
 		"Takes no arguments." },
 
 	// Goober5000 - added wing capability