Don't attempt to migrate empty permissions

bukkit/src/main/java/me/lucko/luckperms/bukkit/migration/MigrationBPermissions.java

@@ -189,10 +189,17 @@ public class MigrationBPermissions extends SubCommand<Object> {
     private static void migrateHolder(World world, Calculable c, PermissionHolder holder) {
         // Migrate the groups permissions in this world
         for (Permission p : c.getPermissions()) {
+            if (p.name().isEmpty()) {
+                continue;
+            }
             holder.setPermission(NodeFactory.make(p.name(), p.isTrue(), "global", world.getName()));
 
             // Include any child permissions
             for (Map.Entry<String, Boolean> child : p.getChildren().entrySet()) {
+                if (child.getKey().isEmpty()) {
+                    continue;
+                }
+
                 holder.setPermission(NodeFactory.make(child.getKey(), child.getValue(), "global", world.getName()));
             }
         }
@@ -209,6 +216,10 @@ public class MigrationBPermissions extends SubCommand<Object> {
 
         // Migrate existing meta
         for (Map.Entry<String, String> meta : c.getMeta().entrySet()) {
+            if (meta.getKey().isEmpty() || meta.getValue().isEmpty()) {
+                continue;
+            }
+
             if (meta.getKey().equalsIgnoreCase("prefix") || meta.getKey().equalsIgnoreCase("suffix")) {
                 holder.setPermission(NodeFactory.makeChatMetaNode(meta.getKey().equalsIgnoreCase("prefix"), c.getPriority(), meta.getValue()).setWorld(world.getName()).build());
                 continue;

bukkit/src/main/java/me/lucko/luckperms/bukkit/migration/MigrationGroupManager.java

@@ -97,10 +97,18 @@ public class MigrationGroupManager extends SubCommand<Object> {
             me.lucko.luckperms.common.core.model.Group group = plugin.getGroupManager().getIfLoaded(groupName);
 
             for (String node : g.getPermissionList()) {
+                if (node.isEmpty()) {
+                    continue;
+                }
+
                 group.setPermission(MigrationUtils.parseNode(node, true).build());
             }
 
             for (String s : g.getInherits()) {
+                if (s.isEmpty()) {
+                    continue;
+                }
+
                 group.setPermission(NodeFactory.make("group." + MigrationUtils.standardizeName(s)));
             }
 
@@ -131,10 +139,18 @@ public class MigrationGroupManager extends SubCommand<Object> {
                 groups.putIfAbsent(groupName, new HashSet<>());
 
                 for (String node : group.getPermissionList()) {
+                    if (node.isEmpty()) {
+                        continue;
+                    }
+
                     groups.get(groupName).add(MigrationUtils.parseNode(node, true).setWorld(worldMappingFunc.apply(world)).build());
                 }
 
                 for (String s : group.getInherits()) {
+                    if (s.isEmpty()) {
+                        continue;
+                    }
+
                     groups.get(groupName).add(NodeFactory.make("group." + MigrationUtils.standardizeName(s), true, null, worldMappingFunc.apply(world)));
                 }
 
@@ -144,6 +160,10 @@ public class MigrationGroupManager extends SubCommand<Object> {
                     String value = group.getVariables().getVarString(key);
                     key = key.toLowerCase();
 
+                    if (key.isEmpty() || value.isEmpty()) {
+                        continue;
+                    }
+
                     if (key.equals("build")) {
                         continue;
                     }
@@ -172,12 +192,17 @@ public class MigrationGroupManager extends SubCommand<Object> {
                 users.putIfAbsent(uuid, new HashSet<>());
 
                 for (String node : user.getPermissionList()) {
+                    if (node.isEmpty()) {
+                        continue;
+                    }
+
                     users.get(uuid).add(MigrationUtils.parseNode(node, true).setWorld(worldMappingFunc.apply(world)).build());
                 }
 
                 // Collect sub groups
                 String finalWorld = worldMappingFunc.apply(world);
                 users.get(uuid).addAll(user.subGroupListStringCopy().stream()
+                        .filter(n -> !n.isEmpty())
                         .map(n -> "group." + MigrationUtils.standardizeName(n))
                         .map(n -> NodeFactory.make(n, true, null, finalWorld))
                         .collect(Collectors.toSet())
@@ -191,6 +216,10 @@ public class MigrationGroupManager extends SubCommand<Object> {
                     String value = user.getVariables().getVarString(key);
                     key = key.toLowerCase();
 
+                    if (key.isEmpty() || value.isEmpty()) {
+                        continue;
+                    }
+
                     if (key.equals("build")) {
                         continue;
                     }

bukkit/src/main/java/me/lucko/luckperms/bukkit/migration/MigrationPermissionsEx.java

@@ -106,6 +106,10 @@ public class MigrationPermissionsEx extends SubCommand<Object> {
 
             try {
                 for (String node : group.getOwnPermissions(null)) {
+                    if (node.isEmpty()) {
+                        continue;
+                    }
+
                     lpGroup.setPermission(MigrationUtils.parseNode(node, true).build());
                 }
             } catch (NullPointerException ignored) {
@@ -113,7 +117,15 @@ public class MigrationPermissionsEx extends SubCommand<Object> {
             }
 
             for (String world : worlds) {
+                if (world.isEmpty()) {
+                    continue;
+                }
+
                 for (String node : group.getOwnPermissions(world)) {
+                    if (node.isEmpty()) {
+                        continue;
+                    }
+
                     lpGroup.setPermission(MigrationUtils.parseNode(node, true).setWorld(world.toLowerCase()).build());
                 }
             }
@@ -123,6 +135,10 @@ public class MigrationPermissionsEx extends SubCommand<Object> {
             }
 
             for (String world : worlds) {
+                if (world.isEmpty()) {
+                    continue;
+                }
+
                 for (PermissionGroup g : group.getParents(world)) {
                     lpGroup.setPermission(NodeFactory.make("group." + MigrationUtils.standardizeName(g.getName()), true, "global", world.toLowerCase()));
                 }
@@ -176,6 +192,10 @@ public class MigrationPermissionsEx extends SubCommand<Object> {
 
             try {
                 for (String node : user.getOwnPermissions(null)) {
+                    if (node.isEmpty()) {
+                        continue;
+                    }
+
                     lpUser.setPermission(MigrationUtils.parseNode(node, true).build());
                 }
             } catch (NullPointerException ignored) {
@@ -183,17 +203,37 @@ public class MigrationPermissionsEx extends SubCommand<Object> {
             }
 
             for (String world : worlds) {
+                if (world.isEmpty()) {
+                    continue;
+                }
+
                 for (String node : user.getOwnPermissions(world)) {
+                    if (node.isEmpty()) {
+                        continue;
+                    }
+
                     lpUser.setPermission(MigrationUtils.parseNode(node, true).setWorld(world.toLowerCase()).build());
                 }
             }
 
             for (String g : user.getGroupNames()) {
+                if (g.isEmpty()) {
+                    continue;
+                }
+
                 lpUser.setPermission(NodeFactory.make("group." + MigrationUtils.standardizeName(g)));
             }
 
             for (String world : worlds) {
+                if (world.isEmpty()) {
+                    continue;
+                }
+
                 for (String g : user.getGroupNames(world)) {
+                    if (g.isEmpty()) {
+                        continue;
+                    }
+
                     lpUser.setPermission(NodeFactory.make("group." + MigrationUtils.standardizeName(g), true, "global", world.toLowerCase()));
                 }
             }

bungee/src/main/java/me/lucko/luckperms/bungee/migration/MigrationBungeePerms.java

@@ -88,18 +88,30 @@ public class MigrationBungeePerms extends SubCommand<Object> {
 
             // Migrate global perms
             for (String perm : g.getPerms()) {
+                if (perm.isEmpty()) {
+                    continue;
+                }
+
                 group.setPermission(MigrationUtils.parseNode(perm, true).build());
             }
 
             // Migrate per-server perms
             for (Map.Entry<String, Server> e : g.getServers().entrySet()) {
                 for (String perm : e.getValue().getPerms()) {
+                    if (perm.isEmpty()) {
+                        continue;
+                    }
+
                     group.setPermission(MigrationUtils.parseNode(perm, true).setWorld(e.getKey()).build());
                 }
 
                 // Migrate per-world perms
                 for (Map.Entry<String, World> we : e.getValue().getWorlds().entrySet()) {
                     for (String perm : we.getValue().getPerms()) {
+                        if (perm.isEmpty()) {
+                            continue;
+                        }
+
                         group.setPermission(MigrationUtils.parseNode(perm, true).setServer(e.getKey()).setWorld(we.getKey()).build());
                     }
                 }
@@ -107,6 +119,10 @@ public class MigrationBungeePerms extends SubCommand<Object> {
 
             // Migrate any parent groups
             for (String inherit : g.getInheritances()) {
+                if (inherit.isEmpty()) {
+                    continue;
+                }
+
                 group.setPermission(NodeFactory.make("group." + MigrationUtils.standardizeName(inherit)));
             }
 
@@ -145,18 +161,30 @@ public class MigrationBungeePerms extends SubCommand<Object> {
 
             // Migrate global perms
             for (String perm : u.getPerms()) {
+                if (perm.isEmpty()) {
+                    continue;
+                }
+
                 user.setPermission(MigrationUtils.parseNode(perm, true).build());
             }
 
             // Migrate per-server perms
             for (Map.Entry<String, Server> e : u.getServers().entrySet()) {
                 for (String perm : e.getValue().getPerms()) {
+                    if (perm.isEmpty()) {
+                        continue;
+                    }
+
                     user.setPermission(MigrationUtils.parseNode(perm, true).setWorld(e.getKey()).build());
                 }
 
                 // Migrate per-world perms
                 for (Map.Entry<String, World> we : e.getValue().getWorlds().entrySet()) {
                     for (String perm : we.getValue().getPerms()) {
+                        if (perm.isEmpty()) {
+                            continue;
+                        }
+
                         user.setPermission(MigrationUtils.parseNode(perm, true).setServer(e.getKey()).setWorld(we.getKey()).build());
                     }
                 }
@@ -164,6 +192,10 @@ public class MigrationBungeePerms extends SubCommand<Object> {
 
             // Migrate groups
             for (String group : u.getGroupsString()) {
+                if (group.isEmpty()) {
+                    continue;
+                }
+
                 user.setPermission(NodeFactory.make("group." + MigrationUtils.standardizeName(group)));
             }
 

sponge/src/main/java/me/lucko/luckperms/sponge/migration/SpongeMigrationUtils.java

@@ -55,6 +55,10 @@ public class SpongeMigrationUtils {
             ContextSet context = Util.convertContexts(e.getKey());
 
             for (Map.Entry<String, Boolean> perm : e.getValue().entrySet()) {
+                if (perm.getKey().isEmpty()) {
+                    continue;
+                }
+
                 holder.setPermission(NodeFactory.newBuilder(perm.getKey()).withExtraContext(context).setValue(perm.getValue()).build());
             }
         }
@@ -65,6 +69,10 @@ public class SpongeMigrationUtils {
             ContextSet context = Util.convertContexts(e.getKey());
 
             for (Map.Entry<String, String> opt : e.getValue().entrySet()) {
+                if (opt.getKey().isEmpty() || opt.getValue().isEmpty()) {
+                    continue;
+                }
+
                 if (opt.getKey().equalsIgnoreCase("prefix")) {
                     holder.setPermission(NodeFactory.makePrefixNode(priority, opt.getValue()).withExtraContext(context).setValue(true).build());
                 } else if (opt.getKey().equalsIgnoreCase("suffix")) {