The keyword reminder text box now tries to run the script to see if it contains errors

src/data/action/keyword.cpp

@@ -52,8 +52,10 @@ void AddKeywordAction::perform(bool to_undo) {
 
 // ----------------------------------------------------------------------------- : Changing keywords
 
-KeywordReminderTextValue::KeywordReminderTextValue(const TextFieldP& field, Keyword* keyword, bool editable)
+KeywordReminderTextValue::KeywordReminderTextValue(Set& set, const TextFieldP& field, Keyword* keyword, bool editable)
 	: KeywordTextValue(field, keyword, &keyword->reminder.getUnparsed(), editable)
+	, set(set)
+	, keyword(*keyword)
 {}
 
 void KeywordReminderTextValue::store() {
@@ -67,10 +69,12 @@ void KeywordReminderTextValue::store() {
 	vector<ScriptParseError> parse_errors;
 	ScriptP new_script = parse(new_value, nullptr, true, parse_errors);
 	if (parse_errors.empty()) {
-		// parsed okay, assign
-		errors.clear();
-		keyword.reminder.getScriptP()  = new_script;
-		keyword.reminder.getUnparsed() = new_value;
+		// parsed okay
+		if (checkScript(new_script)) {
+			// also runs okay, assign
+			keyword.reminder.getScriptP()  = new_script;
+			keyword.reminder.getUnparsed() = new_value;
+		}
 	} else {
 		// parse errors, report
 		errors = ScriptParseErrors(parse_errors).what();
@@ -172,6 +176,23 @@ void KeywordReminderTextValue::highlight(const String& code, const vector<Script
 	value = new_value;
 }
 
+bool KeywordReminderTextValue::checkScript(const ScriptP& script) {
+	Context& ctx = set.cards.empty() ? set.getContext() : set.getContext(set.cards.front());
+	size_t scope = ctx.openScope();
+	try {
+		for (size_t i = 0 ; i < keyword.parameters.size() ; ++i) {
+			String param = String(_("param")) << (int)(i+1);
+			ctx.setVariable(param, to_script(param));
+		}
+		script->eval(ctx);
+		errors.clear();
+	} catch (const Error& e) {
+		errors = e.what();
+	}
+	ctx.closeScope(scope);
+	return errors.empty();
+}
+
 // ----------------------------------------------------------------------------- : Changing keywords : mode
 
 ChangeKeywordModeAction::ChangeKeywordModeAction(Keyword& keyword, const String& new_mode)

src/data/action/keyword.hpp

@@ -70,9 +70,11 @@ class KeywordTextValue : public FakeTextValue {
 /// A FakeTextValue that is used to edit reminder text scripts
 class KeywordReminderTextValue : public KeywordTextValue {
   public:
-	KeywordReminderTextValue(const TextFieldP& field, Keyword* keyword, bool editable);
+	KeywordReminderTextValue(Set& set, const TextFieldP& field, Keyword* keyword, bool editable);
 	
 	String errors; ///< Errors in the script
+	Set&   set;    ///< Set this keyword is in (for script checking)
+	Keyword& keyword; ///< The keyword we are the reminder text of
 	
 	/// Try to compile the script
 	virtual void store();
@@ -81,6 +83,9 @@ class KeywordReminderTextValue : public KeywordTextValue {
 	
 	/// Syntax highlight, and store in value
 	void highlight(const String& code, const vector<ScriptParseError>& errors);
+	
+	/// Check the script for errors
+	bool checkScript(const ScriptP& script);
 };
 
 /// Changing the mode of a keyword

src/gui/set/keywords_panel.cpp

@@ -313,7 +313,7 @@ void KeywordsPanel::onKeywordSelect(KeywordSelectEvent& ev) {
 		keyword ->setValue(new_intrusive5<KeywordTextValue>        (keyword->getFieldP(),  &kw, &kw.keyword, !kw.fixed, true));
 		match   ->setValue(new_intrusive4<KeywordTextValue>        (match->getFieldP(),    &kw, &kw.match,   !kw.fixed));
 		rules   ->setValue(new_intrusive4<KeywordTextValue>        (rules->getFieldP(),    &kw, &kw.rules,   !kw.fixed));
-		intrusive_ptr<KeywordReminderTextValue> reminder_value(new KeywordReminderTextValue(reminder->getFieldP(), &kw,              !kw.fixed));
+		intrusive_ptr<KeywordReminderTextValue> reminder_value(new KeywordReminderTextValue(*set, reminder->getFieldP(), &kw, !kw.fixed));
 		reminder->setValue(reminder_value);
 		errors->SetLabel(reminder_value->errors);
 		add_param->Enable(!kw.fixed && !set->game->keyword_parameter_types.empty());