Localized sorting

src/debug_menu.cpp

@@ -1235,16 +1235,16 @@ void debug()
                     if( elem == vproto_id( "custom" ) ) {
                         continue;
                     }
-                    veh_strings.emplace_back( elem->name, elem );
+                    veh_strings.emplace_back( _( elem->name ), elem );
                 }
-                std::sort( veh_strings.begin(), veh_strings.end() );
+                std::sort( veh_strings.begin(), veh_strings.end(), localized_compare );
                 uilist veh_menu;
                 veh_menu.text = _( "Choose vehicle to spawn" );
                 int menu_ind = 0;
                 for( auto &elem : veh_strings ) {
                     //~ Menu entry in vehicle wish menu: 1st string: displayed name, 2nd string: internal name of vehicle
                     veh_menu.addentry( menu_ind, true, MENU_AUTOASSIGN, _( "%1$s (%2$s)" ),
-                                       _( elem.first ), elem.second.c_str() );
+                                       elem.first, elem.second.c_str() );
                     ++menu_ind;
                 }
                 veh_menu.query();

src/translations.cpp

@@ -686,3 +686,8 @@ std::string operator+( const translation &lhs, const translation &rhs )
 {
     return lhs.translated() + rhs.translated();
 }
+
+bool localized_comparator::operator()( const std::string &l, const std::string &r ) const
+{
+    return std::locale()( l, r );
+}

src/translations.h

@@ -244,4 +244,33 @@ std::string operator+( const translation &lhs, const std::string &rhs );
 std::string operator+( const std::string &lhs, const translation &rhs );
 std::string operator+( const translation &lhs, const translation &rhs );
 
+// Localized comparison operator, intended for sorting strings when they should
+// be sorted according to the user's locale.
+//
+// For convenience, it also sorts pairs recursively, because a common
+// requirement is to sort some list of objects by their names, and this can be
+// achieved by sorting a list of pairs where the first element of the pair is
+// the translated name.
+struct localized_comparator {
+    template<typename T, typename U>
+    bool operator()( const std::pair<T, U> &l, const std::pair<T, U> &r ) const {
+        if( ( *this )( l.first, r.first ) ) {
+            return true;
+        }
+        if( ( *this )( r.first, l.first ) ) {
+            return false;
+        }
+        return ( *this )( l.second, r.second );
+    }
+
+    template<typename T>
+    bool operator()( const T &l, const T &r ) const {
+        return l < r;
+    }
+
+    bool operator()( const std::string &, const std::string & ) const;
+};
+
+constexpr localized_comparator localized_compare;
+
 #endif // CATA_SRC_TRANSLATIONS_H