Don't replace unchanged 1.12->1.13 translations with hard text

Also add the remaining unchanged keys to the file
Fixes #3284

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_13to1_12_2/data/MappingData.java

@@ -94,37 +94,38 @@ public class MappingData extends MappingDataBase {
             }
         }
 
-        Map<String, String> translateData = GsonUtil.getGson().fromJson(
+        Map<String, String> translationMappingData = GsonUtil.getGson().fromJson(
                 new InputStreamReader(MappingData.class.getClassLoader().getResourceAsStream("assets/viaversion/data/mapping-lang-1.12-1.13.json")),
                 new TypeToken<Map<String, String>>() {
                 }.getType());
-        try {
-            String[] lines;
-            try (Reader reader = new InputStreamReader(MappingData.class.getClassLoader()
-                    .getResourceAsStream("assets/viaversion/data/en_US.properties"), StandardCharsets.UTF_8)) {
-                lines = CharStreams.toString(reader).split("\n");
-            }
-            for (String line : lines) {
-                if (line.isEmpty()) {
-                    continue;
-                }
 
-                String[] keyAndTranslation = line.split("=", 2);
+        String[] unmappedTranslationLines;
-                if (keyAndTranslation.length != 2) {
+        try (Reader reader = new InputStreamReader(MappingData.class.getClassLoader()
-                    continue;
+                .getResourceAsStream("assets/viaversion/data/en_US.properties"), StandardCharsets.UTF_8)) {
-                }
+            unmappedTranslationLines = CharStreams.toString(reader).split("\n");
-
-                String key = keyAndTranslation[0];
-                String translation = keyAndTranslation[1].replaceAll("%(\\d\\$)?d", "%$1s").trim();
-                mojangTranslation.put(key, translation);
-
-                String dataValue = translateData.get(key);
-                if (dataValue != null) {
-                    translateMapping.put(key, dataValue);
-                }
-            }
         } catch (IOException e) {
-            e.printStackTrace();
+            throw new RuntimeException(e);
+        }
+
+        for (String line : unmappedTranslationLines) {
+            if (line.isEmpty()) {
+                continue;
+            }
+
+            String[] keyAndTranslation = line.split("=", 2);
+            if (keyAndTranslation.length != 2) {
+                continue;
+            }
+
+            String key = keyAndTranslation[0];
+            String translation = keyAndTranslation[1].replaceAll("%(\\d\\$)?d", "%$1s").trim();
+            mojangTranslation.put(key, translation);
+
+            // Null values in the file mean the key did not change AND the translation has the same amount of placeholders still
+            if (translationMappingData.containsKey(key)) {
+                String mappedKey = translationMappingData.get(key);
+                translateMapping.put(key, mappedKey != null ? mappedKey : key);
+            }
         }
     }
 

common/src/main/resources/assets/viaversion/data/mapping-lang-1.12-1.13.json

@@ -2752,5 +2752,70 @@
   "advancements.story.smelt_iron.title": null,
   "advancements.story.smelt_iron.description": null,
   "advancements.story.upgrade_tools.title": null,
-  "advancements.story.upgrade_tools.description": null
+  "selectWorld.edit.openFolder": null,
+  "selectWorld.edit.save": null,
+  "selectWorld.versionWarning": null,
+  "selectWorld.versionJoinButton": null,
+  "selectWorld.allowCommands.info": null,
+  "multiplayer.downloadingTerrain": null,
+  "multiplayer.disconnect.banned": null,
+  "multiplayer.disconnect.ip_banned": null,
+  "multiplayer.disconnect.kicked": null,
+  "disconnect.loginFailed": null,
+  "disconnect.loginFailedInfo": null,
+  "options.narrator.off": null,
+  "key.mouse.left": null,
+  "key.mouse.middle": null,
+  "key.mouse.right": null,
+  "structure_block.size_failure": null,
+  "death.attack.hotFloor": null,
+  "commands.setidletimeout.success": null,
+  "commands.summon.failed": null,
+  "commands.setblock.failed": null,
+  "commands.fill.success": null,
+  "commands.fill.failed": null,
+  "commands.clone.success": null,
+  "commands.clone.failed": null,
+  "commands.time.query": null,
+  "commands.op.success": null,
+  "commands.deop.success": null,
+  "commands.banip.invalid": null,
+  "commands.save.enabled": null,
+  "commands.save.disabled": null,
+  "commands.save.success": null,
+  "commands.advancement.criterionNotFound": null,
+  "commands.reload.success": null,
+  "commands.scoreboard.objectives.add.success": null,
+  "commands.scoreboard.objectives.remove.success": null,
+  "commands.scoreboard.objectives.list.empty": null,
+  "commands.scoreboard.players.list.empty": null,
+  "commands.defaultgamemode.success": null,
+  "commands.difficulty.success": null,
+  "commands.setworldspawn.success": null,
+  "commands.worldborder.center.success": null,
+  "commands.locate.success": null,
+  "subtitles.entity.generic.small_fall": null,
+  "subtitles.entity.llama.angry": null,
+  "subtitles.item.armor.equip": null,
+  "subtitles.item.armor.equip_elytra": null,
+  "debug.reload_chunks.help": null,
+  "debug.show_hitboxes.help": null,
+  "debug.clear_chat.help": null,
+  "debug.cycle_renderdistance.help": null,
+  "debug.chunk_boundaries.help": null,
+  "debug.advanced_tooltips.help": null,
+  "debug.creative_spectator.help": null,
+  "debug.pause_focus.help": null,
+  "debug.help.help": null,
+  "debug.reload_resourcepacks.help": null,
+  "advancements.adventure.sleep_in_bed.title": null,
+  "advancements.adventure.sniper_duel.title": null,
+  "advancements.adventure.sniper_duel.description": null,
+  "advancements.end.elytra.description": null,
+  "advancements.end.respawn_dragon.description": null,
+  "advancements.nether.get_wither_skull.description": null,
+  "advancements.nether.fast_travel.description": null,
+  "advancements.nether.uneasy_alliance.description": null,
+  "advancements.story.cure_zombie_villager.description": null,
+  "advancements.story.follow_ender_eye.description": null
 }