Merge pull request #1236 from ViaVersion/master

merge master into dev

bungee/src/main/java/us/myles/ViaVersion/bungee/handlers/BungeeServerHandler.java

@@ -1,6 +1,5 @@
 package us.myles.ViaVersion.bungee.handlers;
 
-import com.google.common.base.Joiner;
 import net.md_5.bungee.api.connection.ProxiedPlayer;
 import net.md_5.bungee.api.event.ServerConnectEvent;
 import net.md_5.bungee.api.event.ServerConnectedEvent;
@@ -29,8 +28,11 @@ import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
 import java.util.List;
+import java.util.Objects;
 import java.util.UUID;
+import java.util.stream.Collectors;
 
 public class BungeeServerHandler implements Listener {
     private static Method getHandshake;
@@ -152,23 +154,28 @@ public class BungeeServerHandler implements Listener {
                         String channel = plMsg.getTag();
                         int id1_13 = ProtocolVersion.v1_13.getId();
                         if (previousServerProtocol != -1) {
+                            String oldChannel = channel;
                             if (previousServerProtocol < id1_13 && protocolId >= id1_13) {
                                 channel = InventoryPackets.getNewPluginChannelId(channel);
-                                if (channel.equals("minecraft:register")) {
+                                if (channel == null) {
-                                    String[] channels = new String(plMsg.getData(), StandardCharsets.UTF_8).split("\0");
+                                    throw new RuntimeException(oldChannel + " found in relayMessages");
-                                    for (int i = 0; i < channels.length; i++) {
-                                        channels[i] = InventoryPackets.getNewPluginChannelId(channels[i]);
                                 }
-                                    plMsg.setData(Joiner.on('\0').join(channels).getBytes(StandardCharsets.UTF_8));
+                                if (channel.equals("minecraft:register")) {
+                                    plMsg.setData(Arrays.stream(new String(plMsg.getData(), StandardCharsets.UTF_8).split("\0"))
+                                            .map(InventoryPackets::getNewPluginChannelId)
+                                            .filter(Objects::nonNull)
+                                            .collect(Collectors.joining("\0")).getBytes(StandardCharsets.UTF_8));
                                 }
                             } else if (previousServerProtocol >= id1_13 && protocolId < id1_13) {
                                 channel = InventoryPackets.getOldPluginChannelId(channel);
-                                if (channel.equals("REGISTER")) {
+                                if (channel == null) {
-                                    String[] channels = new String(plMsg.getData(), StandardCharsets.UTF_8).split("\0");
+                                    throw new RuntimeException(oldChannel + " found in relayMessages");
-                                    for (int i = 0; i < channels.length; i++) {
-                                        channels[i] = InventoryPackets.getOldPluginChannelId(channels[i]);
                                 }
-                                    plMsg.setData(Joiner.on('\0').join(channels).getBytes(StandardCharsets.UTF_8));
+                                if (channel.equals("REGISTER")) {
+                                    plMsg.setData(Arrays.stream(new String(plMsg.getData(), StandardCharsets.UTF_8).split("\0"))
+                                            .map(InventoryPackets::getOldPluginChannelId)
+                                            .filter(Objects::nonNull)
+                                            .collect(Collectors.joining("\0")).getBytes(StandardCharsets.UTF_8));
                                 }
                             }
                         }

common/src/main/java/us/myles/ViaVersion/api/type/types/minecraft/NBTType.java

@@ -1,6 +1,7 @@
 package us.myles.ViaVersion.api.type.types.minecraft;
 
 import com.github.steveice10.opennbt.NBTIO;
+import com.github.steveice10.opennbt.tag.TagRegistry;
 import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import com.google.common.base.Preconditions;
 import io.netty.buffer.ByteBuf;
@@ -14,6 +15,13 @@ import java.io.DataOutput;
 import java.io.DataOutputStream;
 
 public class NBTType extends Type<CompoundTag> {
+    static {
+        // We don't need them
+        TagRegistry.unregister(60);
+        TagRegistry.unregister(61);
+        TagRegistry.unregister(65);
+    }
+
     public NBTType() {
         super(CompoundTag.class);
     }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/blockconnections/AbstractFenceConnectionHandler.java

@@ -4,6 +4,8 @@ import lombok.Getter;
 import us.myles.ViaVersion.api.data.UserConnection;
 import us.myles.ViaVersion.api.minecraft.BlockFace;
 import us.myles.ViaVersion.api.minecraft.Position;
+import us.myles.ViaVersion.api.protocol.ProtocolVersion;
+import us.myles.ViaVersion.protocols.base.ProtocolInfo;
 
 import java.util.HashMap;
 import java.util.HashSet;
@@ -47,10 +49,11 @@ public abstract class AbstractFenceConnectionHandler extends ConnectionHandler {
 
     protected byte getStates(UserConnection user, Position position, int blockState) {
         byte states = 0;
-        if (connects(BlockFace.EAST, getBlockData(user, position.getRelative(BlockFace.EAST)))) states |= 1;
+        boolean pre1_12 = user.get(ProtocolInfo.class).getServerProtocolVersion() < ProtocolVersion.v1_12.getId();
-        if (connects(BlockFace.NORTH, getBlockData(user, position.getRelative(BlockFace.NORTH)))) states |= 2;
+        if (connects(BlockFace.EAST, getBlockData(user, position.getRelative(BlockFace.EAST)), pre1_12)) states |= 1;
-        if (connects(BlockFace.SOUTH, getBlockData(user, position.getRelative(BlockFace.SOUTH)))) states |= 4;
+        if (connects(BlockFace.NORTH, getBlockData(user, position.getRelative(BlockFace.NORTH)), pre1_12)) states |= 2;
-        if (connects(BlockFace.WEST, getBlockData(user, position.getRelative(BlockFace.WEST)))) states |= 8;
+        if (connects(BlockFace.SOUTH, getBlockData(user, position.getRelative(BlockFace.SOUTH)), pre1_12)) states |= 4;
+        if (connects(BlockFace.WEST, getBlockData(user, position.getRelative(BlockFace.WEST)), pre1_12)) states |= 8;
         return states;
     }
 
@@ -65,7 +68,9 @@ public abstract class AbstractFenceConnectionHandler extends ConnectionHandler {
         return newBlockState == null ? blockState : newBlockState;
     }
 
-    protected boolean connects(BlockFace side, int blockState) {
+    protected boolean connects(BlockFace side, int blockState, boolean pre1_12) {
-        return blockStates.contains(blockState) || blockConnections != null && ConnectionData.blockConnectionData.containsKey(blockState) && ConnectionData.blockConnectionData.get(blockState).connectsTo(blockConnections, side.opposite());
+        return blockStates.contains(blockState) || blockConnections != null
+                && ConnectionData.blockConnectionData.containsKey(blockState)
+                && ConnectionData.blockConnectionData.get(blockState).connectsTo(blockConnections, side.opposite(), pre1_12);
     }
 }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/blockconnections/BlockData.java

@@ -6,14 +6,20 @@ import java.util.HashMap;
 import java.util.Map;
 
 public class BlockData {
-    private Map<String, Boolean[]> connectData = new HashMap<>();
+    private Map<String, boolean[]> connectData = new HashMap<>();
 
-    public void put(String key, Boolean[] booleans) {
+    public void put(String key, boolean[] booleans) {
         connectData.put(key, booleans);
     }
 
-    public boolean connectsTo(String blockConnection, BlockFace face) {
+    public boolean connectsTo(String blockConnection, BlockFace face, boolean pre1_12AbstractFence) {
-        final Boolean[] booleans = connectData.get(blockConnection);
+        boolean[] booleans = null;
+        if (pre1_12AbstractFence) {
+            booleans = connectData.get("allFalseIfStairPre1_12"); // https://minecraft.gamepedia.com/Java_Edition_1.12
+        }
+        if (booleans == null) {
+            booleans = connectData.get(blockConnection);
+        }
         return booleans != null && booleans[face.ordinal()];
     }
 }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/blockconnections/ChorusPlantConnectionHandler.java

@@ -3,10 +3,11 @@ package us.myles.ViaVersion.protocols.protocol1_13to1_12_2.blockconnections;
 import us.myles.ViaVersion.api.data.UserConnection;
 import us.myles.ViaVersion.api.minecraft.BlockFace;
 import us.myles.ViaVersion.api.minecraft.Position;
+import us.myles.ViaVersion.api.protocol.ProtocolVersion;
+import us.myles.ViaVersion.protocols.base.ProtocolInfo;
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Map;
 
 public class ChorusPlantConnectionHandler extends AbstractFenceConnectionHandler {
     private int endstone;
@@ -46,13 +47,13 @@ public class ChorusPlantConnectionHandler extends AbstractFenceConnectionHandler
     @Override
     protected byte getStates(UserConnection user, Position position, int blockState) {
         byte states = super.getStates(user, position, blockState);
-        if (connects(BlockFace.TOP, getBlockData(user, position.getRelative(BlockFace.TOP)))) states |= 16;
+        if (connects(BlockFace.TOP, getBlockData(user, position.getRelative(BlockFace.TOP)), false)) states |= 16;
-        if (connects(BlockFace.BOTTOM, getBlockData(user, position.getRelative(BlockFace.BOTTOM)))) states |= 32;
+        if (connects(BlockFace.BOTTOM, getBlockData(user, position.getRelative(BlockFace.BOTTOM)), false)) states |= 32;
         return states;
     }
 
     @Override
-    protected boolean connects(BlockFace side, int blockState) {
+    protected boolean connects(BlockFace side, int blockState, boolean pre1_12) {
         return getBlockStates().contains(blockState) || (side == BlockFace.BOTTOM && blockState == endstone);
     }
 }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/blockconnections/ConnectionData.java

@@ -212,17 +212,18 @@ public class ConnectionData {
                 for (Entry<String, JsonElement> type : entry.getValue().getAsJsonObject().entrySet()) {
                     String name = type.getKey();
                     JsonObject object = type.getValue().getAsJsonObject();
-                    Boolean[] data = new Boolean[6];
+                    boolean[] data = new boolean[6];
                     for (BlockFace value : BlockFace.values()) {
                         String face = value.toString().toLowerCase();
                         if (object.has(face)) {
                             data[value.ordinal()] = object.getAsJsonPrimitive(face).getAsBoolean();
-                        } else {
-                            data[value.ordinal()] = false;
                         }
                     }
                     blockData.put(name, data);
                 }
+                if (entry.getKey().contains("stairs")) {
+                    blockData.put("allFalseIfStairPre1_12", new boolean[6]);
+                }
                 blockConnectionData.put(id, blockData);
             }
         }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/blockconnections/RedstoneConnectionHandler.java

@@ -83,6 +83,6 @@ public class RedstoneConnectionHandler extends ConnectionHandler {
 
     private boolean connects(BlockFace side, int blockState) {
         final BlockData blockData = ConnectionData.blockConnectionData.get(blockState);
-        return blockData != null && blockData.connectsTo("redstoneConnections", side.opposite());
+        return blockData != null && blockData.connectsTo("redstoneConnections", side.opposite(), false);
     }
 }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/data/BlockIdData.java

@@ -13,6 +13,7 @@ import java.util.Map;
 public class BlockIdData {
     public static Map<String, String[]> blockIdMapping;
     public static Map<String, String[]> fallbackReverseMapping;
+    public static Map<Integer, String> numberIdToString;
 
     public static void init() {
         InputStream stream = MappingData.class.getClassLoader()
@@ -39,5 +40,22 @@ public class BlockIdData {
                 // Ignored
             }
         }
+
+        InputStream blockS = MappingData.class.getClassLoader()
+                .getResourceAsStream("assets/viaversion/data/blockNumberToString1.12.json");
+        InputStreamReader blockR = new InputStreamReader(blockS);
+        try {
+            numberIdToString = new HashMap<>((Map<Integer, String>) GsonUtil.getGson().fromJson(
+                    blockR,
+                    new TypeToken<Map<Integer, String>>() {
+                    }.getType()
+            ));
+        } finally {
+            try {
+                blockR.close();
+            } catch (IOException ignored) {
+                // Ignored
+            }
+        }
     }
 }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/packets/InventoryPackets.java

@@ -4,7 +4,7 @@ import com.github.steveice10.opennbt.conversion.ConverterRegistry;
 import com.github.steveice10.opennbt.tag.builtin.*;
 import com.google.common.base.Joiner;
 import com.google.common.base.Optional;
-import com.google.common.io.BaseEncoding;
+import com.google.common.primitives.Ints;
 import us.myles.ViaVersion.api.PacketWrapper;
 import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.minecraft.item.Item;
@@ -159,8 +159,12 @@ public class InventoryPackets {
                                 wrapper.passthrough(Type.INT); // Maximum number of trade uses
                             }
                         } else {
+                            String old = channel;
                             channel = getNewPluginChannelId(channel);
                             if (channel == null) {
+                                if (!Via.getConfig().isSuppress1_13ConversionErrors() || Via.getManager().isDebug()) {
+                                    Via.getPlatform().getLogger().warning("Ignoring outgoing plugin message with channel: " + old);
+                                }
                                 wrapper.cancel();
                                 return;
                             } else if (channel.equals("minecraft:register") || channel.equals("minecraft:unregister")) {
@@ -171,7 +175,7 @@ public class InventoryPackets {
                                     if (rewritten != null) {
                                         rewrittenChannels.add(rewritten);
                                     } else if (!Via.getConfig().isSuppress1_13ConversionErrors() || Via.getManager().isDebug()) {
-                                        Via.getPlatform().getLogger().warning("Ignoring plugin channel in REGISTER: " + channels[i]);
+                                        Via.getPlatform().getLogger().warning("Ignoring plugin channel in outgoing REGISTER: " + channels[i]);
                                     }
                                 }
                                 wrapper.write(Type.REMAINING_BYTES, Joiner.on('\0').join(rewrittenChannels).getBytes(StandardCharsets.UTF_8));
@@ -238,8 +242,12 @@ public class InventoryPackets {
                     @Override
                     public void handle(PacketWrapper wrapper) throws Exception {
                         String channel = wrapper.get(Type.STRING, 0);
+                        String old = channel;
                         channel = getOldPluginChannelId(channel);
                         if (channel == null) {
+                            if (!Via.getConfig().isSuppress1_13ConversionErrors() || Via.getManager().isDebug()) {
+                                Via.getPlatform().getLogger().warning("Ignoring incoming plugin message with channel: " + old);
+                            }
                             wrapper.cancel();
                             return;
                         } else if (channel.equals("REGISTER") || channel.equals("UNREGISTER")) {
@@ -250,7 +258,7 @@ public class InventoryPackets {
                                 if (rewritten != null) {
                                     rewrittenChannels.add(rewritten);
                                 } else if (!Via.getConfig().isSuppress1_13ConversionErrors() || Via.getManager().isDebug()) {
-                                    Via.getPlatform().getLogger().warning("Ignoring plugin channel in REGISTER: " + channels[i]);
+                                    Via.getPlatform().getLogger().warning("Ignoring plugin channel in incoming REGISTER: " + channels[i]);
                                 }
                             }
                             wrapper.write(Type.REMAINING_BYTES, Joiner.on('\0').join(rewrittenChannels).getBytes(StandardCharsets.UTF_8));
@@ -381,15 +389,18 @@ public class InventoryPackets {
                 tag.put(ConverterRegistry.convertToTag(NBT_TAG_NAME + "|CanPlaceOn", ConverterRegistry.convertToValue(old))); // There will be data losing
                 for (Tag oldTag : old) {
                     Object value = oldTag.getValue();
-                    String[] newValues = BlockIdData.blockIdMapping.get(value instanceof String
+                    String oldId = value.toString().replace("minecraft:", "");
-                            ? ((String) value).replace("minecraft:", "")
+                    String numberConverted = BlockIdData.numberIdToString.get(Ints.tryParse(oldId));
-                            : null);
+                    if (numberConverted != null) {
+                        oldId = numberConverted;
+                    }
+                    String[] newValues = BlockIdData.blockIdMapping.get(oldId);
                     if (newValues != null) {
                         for (String newValue : newValues) {
                             newCanPlaceOn.add(new StringTag("", newValue));
                         }
                     } else {
-                        newCanPlaceOn.add(oldTag);
+                        newCanPlaceOn.add(new StringTag("", oldId));
                     }
                 }
                 tag.put(newCanPlaceOn);
@@ -400,15 +411,18 @@ public class InventoryPackets {
                 tag.put(ConverterRegistry.convertToTag(NBT_TAG_NAME + "|CanDestroy", ConverterRegistry.convertToValue(old))); // There will be data losing
                 for (Tag oldTag : old) {
                     Object value = oldTag.getValue();
-                    String[] newValues = BlockIdData.blockIdMapping.get(value instanceof String
+                    String oldId = value.toString().replace("minecraft:", "");
-                            ? ((String) value).replace("minecraft:", "")
+                    String numberConverted = BlockIdData.numberIdToString.get(Ints.tryParse(oldId));
-                            : null);
+                    if (numberConverted != null) {
+                        oldId = numberConverted;
+                    }
+                    String[] newValues = BlockIdData.blockIdMapping.get(oldId);
                     if (newValues != null) {
                         for (String newValue : newValues) {
                             newCanDestroy.add(new StringTag("", newValue));
                         }
                     } else {
-                        newCanDestroy.add(oldTag);
+                        newCanDestroy.add(new StringTag("", oldId));
                     }
                 }
                 tag.put(newCanDestroy);
@@ -488,9 +502,7 @@ public class InventoryPackets {
                 return "wdl:request";
             default:
                 return old.matches("([0-9a-z_-]*:)?[0-9a-z_/.-]*") // Identifier regex
-                        ? old
+                        ? old : null;
-                        : "viaversion:legacy/" + BaseEncoding.base32().lowerCase().withPadChar('-').encode(
-                        old.getBytes(StandardCharsets.UTF_8));
         }
     }
 
@@ -710,14 +722,8 @@ public class InventoryPackets {
             case "wdl:request":
                 return "WDL|REQUEST";
             default:
-                return newId.startsWith("viaversion:legacy/") // Our format :)
+                return newId.matches("([0-9a-z_-]*:)?[0-9a-z_/.-]*") // Identifier regex
-                        ? new String(BaseEncoding.base32().lowerCase().withPadChar('-').decode(
+                        ? newId : null;
-                        newId.substring(18)), StandardCharsets.UTF_8)
-                        : newId.startsWith("legacy:")
-                        ? newId.substring(7) // Rewrite BungeeCord's format. It will only prevent kicks, plugins will still be broken because of case-sensitivity *plays sad violin*
-                        : newId.startsWith("bungeecord:legacy/")
-                        ? newId.substring(18)
-                        : newId;
         }
     }
 

common/src/main/resources/assets/viaversion/data/blockNumberToString1.12.json

@@ -0,0 +1,256 @@
+{
+  "0": "air",
+  "1": "stone",
+  "2": "grass",
+  "3": "dirt",
+  "4": "cobblestone",
+  "5": "planks",
+  "6": "sapling",
+  "7": "bedrock",
+  "8": "flowing_water",
+  "9": "water",
+  "10": "flowing_lava",
+  "11": "lava",
+  "12": "sand",
+  "13": "gravel",
+  "14": "gold_ore",
+  "15": "iron_ore",
+  "16": "coal_ore",
+  "17": "log",
+  "18": "leaves",
+  "19": "sponge",
+  "20": "glass",
+  "21": "lapis_ore",
+  "22": "lapis_block",
+  "23": "dispenser",
+  "24": "sandstone",
+  "25": "noteblock",
+  "26": "bed",
+  "27": "golden_rail",
+  "28": "detector_rail",
+  "29": "sticky_piston",
+  "30": "web",
+  "31": "tallgrass",
+  "32": "deadbush",
+  "33": "piston",
+  "34": "piston_head",
+  "35": "wool",
+  "36": "piston_extension",
+  "37": "yellow_flower",
+  "38": "red_flower",
+  "39": "brown_mushroom",
+  "40": "red_mushroom",
+  "41": "gold_block",
+  "42": "iron_block",
+  "43": "double_stone_slab",
+  "44": "stone_slab",
+  "45": "brick_block",
+  "46": "tnt",
+  "47": "bookshelf",
+  "48": "mossy_cobblestone",
+  "49": "obsidian",
+  "50": "torch",
+  "51": "fire",
+  "52": "mob_spawner",
+  "53": "oak_stairs",
+  "54": "chest",
+  "55": "redstone_wire",
+  "56": "diamond_ore",
+  "57": "diamond_block",
+  "58": "crafting_table",
+  "59": "wheat",
+  "60": "farmland",
+  "61": "furnace",
+  "62": "lit_furnace",
+  "63": "standing_sign",
+  "64": "wooden_door",
+  "65": "ladder",
+  "66": "rail",
+  "67": "stone_stairs",
+  "68": "wall_sign",
+  "69": "lever",
+  "70": "stone_pressure_plate",
+  "71": "iron_door",
+  "72": "wooden_pressure_plate",
+  "73": "redstone_ore",
+  "74": "lit_redstone_ore",
+  "75": "unlit_redstone_torch",
+  "76": "redstone_torch",
+  "77": "stone_button",
+  "78": "snow_layer",
+  "79": "ice",
+  "80": "snow",
+  "81": "cactus",
+  "82": "clay",
+  "83": "reeds",
+  "84": "jukebox",
+  "85": "fence",
+  "86": "pumpkin",
+  "87": "netherrack",
+  "88": "soul_sand",
+  "89": "glowstone",
+  "90": "portal",
+  "91": "lit_pumpkin",
+  "92": "cake",
+  "93": "unpowered_repeater",
+  "94": "powered_repeater",
+  "95": "stained_glass",
+  "96": "trapdoor",
+  "97": "monster_egg",
+  "98": "stonebrick",
+  "99": "brown_mushroom_block",
+  "100": "red_mushroom_block",
+  "101": "iron_bars",
+  "102": "glass_pane",
+  "103": "melon_block",
+  "104": "pumpkin_stem",
+  "105": "melon_stem",
+  "106": "vine",
+  "107": "fence_gate",
+  "108": "brick_stairs",
+  "109": "stone_brick_stairs",
+  "110": "mycelium",
+  "111": "waterlily",
+  "112": "nether_brick",
+  "113": "nether_brick_fence",
+  "114": "nether_brick_stairs",
+  "115": "nether_wart",
+  "116": "enchanting_table",
+  "117": "brewing_stand",
+  "118": "cauldron",
+  "119": "end_portal",
+  "120": "end_portal_frame",
+  "121": "end_stone",
+  "122": "dragon_egg",
+  "123": "redstone_lamp",
+  "124": "lit_redstone_lamp",
+  "125": "double_wooden_slab",
+  "126": "wooden_slab",
+  "127": "cocoa",
+  "128": "sandstone_stairs",
+  "129": "emerald_ore",
+  "130": "ender_chest",
+  "131": "tripwire_hook",
+  "132": "tripwire",
+  "133": "emerald_block",
+  "134": "spruce_stairs",
+  "135": "birch_stairs",
+  "136": "jungle_stairs",
+  "137": "command_block",
+  "138": "beacon",
+  "139": "cobblestone_wall",
+  "140": "flower_pot",
+  "141": "carrots",
+  "142": "potatoes",
+  "143": "wooden_button",
+  "144": "skull",
+  "145": "anvil",
+  "146": "trapped_chest",
+  "147": "light_weighted_pressure_plate",
+  "148": "heavy_weighted_pressure_plate",
+  "149": "unpowered_comparator",
+  "150": "powered_comparator",
+  "151": "daylight_detector",
+  "152": "redstone_block",
+  "153": "quartz_ore",
+  "154": "hopper",
+  "155": "quartz_block",
+  "156": "quartz_stairs",
+  "157": "activator_rail",
+  "158": "dropper",
+  "159": "stained_hardened_clay",
+  "160": "stained_glass_pane",
+  "161": "leaves2",
+  "162": "log2",
+  "163": "acacia_stairs",
+  "164": "dark_oak_stairs",
+  "165": "slime",
+  "166": "barrier",
+  "167": "iron_trapdoor",
+  "168": "prismarine",
+  "169": "sea_lantern",
+  "170": "hay_block",
+  "171": "carpet",
+  "172": "hardened_clay",
+  "173": "coal_block",
+  "174": "packed_ice",
+  "175": "double_plant",
+  "176": "standing_banner",
+  "177": "wall_banner",
+  "178": "daylight_detector_inverted",
+  "179": "red_sandstone",
+  "180": "red_sandstone_stairs",
+  "181": "double_stone_slab2",
+  "182": "stone_slab2",
+  "183": "spruce_fence_gate",
+  "184": "birch_fence_gate",
+  "185": "jungle_fence_gate",
+  "186": "dark_oak_fence_gate",
+  "187": "acacia_fence_gate",
+  "188": "spruce_fence",
+  "189": "birch_fence",
+  "190": "jungle_fence",
+  "191": "dark_oak_fence",
+  "192": "acacia_fence",
+  "193": "spruce_door",
+  "194": "birch_door",
+  "195": "jungle_door",
+  "196": "acacia_door",
+  "197": "dark_oak_door",
+  "198": "end_rod",
+  "199": "chorus_plant",
+  "200": "chorus_flower",
+  "201": "purpur_block",
+  "202": "purpur_pillar",
+  "203": "purpur_stairs",
+  "204": "purpur_double_slab",
+  "205": "purpur_slab",
+  "206": "end_bricks",
+  "207": "beetroots",
+  "208": "grass_path",
+  "209": "end_gateway",
+  "210": "repeating_command_block",
+  "211": "chain_command_block",
+  "212": "frosted_ice",
+  "213": "magma",
+  "214": "nether_wart_block",
+  "215": "red_nether_brick",
+  "216": "bone_block",
+  "217": "structure_void",
+  "218": "observer",
+  "219": "white_shulker_box",
+  "220": "orange_shulker_box",
+  "221": "magenta_shulker_box",
+  "222": "light_blue_shulker_box",
+  "223": "yellow_shulker_box",
+  "224": "lime_shulker_box",
+  "225": "pink_shulker_box",
+  "226": "gray_shulker_box",
+  "227": "silver_shulker_box",
+  "228": "cyan_shulker_box",
+  "229": "purple_shulker_box",
+  "230": "blue_shulker_box",
+  "231": "brown_shulker_box",
+  "232": "green_shulker_box",
+  "233": "red_shulker_box",
+  "234": "black_shulker_box",
+  "235": "white_glazed_terracotta",
+  "236": "orange_glazed_terracotta",
+  "237": "magenta_glazed_terracotta",
+  "238": "light_blue_glazed_terracotta",
+  "239": "yellow_glazed_terracotta",
+  "240": "lime_glazed_terracotta",
+  "241": "pink_glazed_terracotta",
+  "242": "gray_glazed_terracotta",
+  "243": "silver_glazed_terracotta",
+  "244": "cyan_glazed_terracotta",
+  "245": "purple_glazed_terracotta",
+  "246": "blue_glazed_terracotta",
+  "247": "brown_glazed_terracotta",
+  "248": "green_glazed_terracotta",
+  "249": "red_glazed_terracotta",
+  "250": "black_glazed_terracotta",
+  "251": "concrete",
+  "252": "concrete_powder",
+  "255": "structure_block"
+}

pom.xml

@@ -81,7 +81,7 @@
         <dependency>
             <groupId>com.github.steveice10</groupId>
             <artifactId>opennbt</artifactId>
-            <version>1.1-SNAPSHOT</version>
+            <version>1.2-SNAPSHOT</version>
             <scope>compile</scope>
             <optional>true</optional>
         </dependency>

velocity/src/main/java/us/myles/ViaVersion/velocity/handlers/VelocityServerHandler.java

@@ -155,15 +155,20 @@ public class VelocityServerHandler {
                         if (previousServerProtocol < id1_13 && protocolId >= id1_13) {
                             ArrayList<String> newChannels = new ArrayList<>();
                             for (String oldChannel : knownChannels) {
-                                newChannels.add(InventoryPackets.getNewPluginChannelId(oldChannel));
+                                String transformed = InventoryPackets.getNewPluginChannelId(oldChannel);
+                                if (transformed != null) {
+                                    newChannels.add(transformed);
+                                }
                             }
                             knownChannels.clear();
                             knownChannels.addAll(newChannels);
-
                         } else if (previousServerProtocol >= id1_13 && protocolId < id1_13) {
                             ArrayList<String> newChannels = new ArrayList<>();
                             for (String oldChannel : knownChannels) {
-                                newChannels.add(InventoryPackets.getOldPluginChannelId(oldChannel));
+                                String transformed = InventoryPackets.getOldPluginChannelId(oldChannel);
+                                if (transformed != null) {
+                                    newChannels.add(transformed);
+                                }
                             }
                             knownChannels.clear();
                             knownChannels.addAll(newChannels);