Keep only one '\0' in NIF strings (bug #6473)

CHANGELOG.md

@@ -87,6 +87,7 @@
     Bug #6429: Wyrmhaven: Can't add AI packages to player
     Bug #6433: Items bound to Quick Keys sometimes do not appear until the Quick Key menu is opened
     Bug #6451: Weapon summoned from Cast When Used item will have the name "None"
+    Bug #6473: Strings from NIF should be parsed only to first null terminator
     Feature #890: OpenMW-CS: Column filtering
     Feature #1465: "Reset" argument for AI functions
     Feature #2554: Modifying an object triggers the instances table to scroll to the corresponding record

components/nif/nifstream.hpp

@@ -149,6 +149,9 @@ public:
         inp->read(str.data(), length);
         if (inp->bad())
             throw std::runtime_error("Failed to read sized string of " + std::to_string(length) + " chars");
+        size_t end = str.find('\0');
+        if (end != std::string::npos)
+            str.erase(end);
         return str;
     }
     ///Read in a string of the length specified in the file