Abstract out the process of traversing the inheritance tree, add configurable option to choose which algorithm to use (#719)

sponge/src/main/java/me/lucko/luckperms/sponge/LPSpongePlugin.java

@@ -51,6 +51,7 @@ import me.lucko.luckperms.common.dependencies.DependencyRegistry;
 import me.lucko.luckperms.common.dependencies.classloader.PluginClassLoader;
 import me.lucko.luckperms.common.dependencies.classloader.ReflectionClassLoader;
 import me.lucko.luckperms.common.event.EventFactory;
+import me.lucko.luckperms.common.inheritance.InheritanceHandler;
 import me.lucko.luckperms.common.locale.LocaleManager;
 import me.lucko.luckperms.common.locale.NoopLocaleManager;
 import me.lucko.luckperms.common.locale.SimpleLocaleManager;
@@ -179,6 +180,7 @@ public class LPSpongePlugin implements LuckPermsSpongePlugin {
     private LocaleManager localeManager;
     private PluginClassLoader pluginClassLoader;
     private DependencyManager dependencyManager;
+    private InheritanceHandler inheritanceHandler;
     private CachedStateManager cachedStateManager;
     private ContextManager<Subject> contextManager;
     private CalculatorFactory calculatorFactory;
@@ -242,6 +244,7 @@ public class LPSpongePlugin implements LuckPermsSpongePlugin {
 
         // load internal managers
         getLog().info("Loading internal permission managers...");
+        this.inheritanceHandler = new InheritanceHandler(this);
         this.userManager = new SpongeUserManager(this);
         this.groupManager = new SpongeGroupManager(this);
         this.trackManager = new StandardTrackManager(this);
@@ -609,6 +612,11 @@ public class LPSpongePlugin implements LuckPermsSpongePlugin {
         return this.contextManager;
     }
 
+    @Override
+    public InheritanceHandler getInheritanceHandler() {
+        return this.inheritanceHandler;
+    }
+
     @Override
     public CalculatorFactory getCalculatorFactory() {
         return this.calculatorFactory;

sponge/src/main/java/me/lucko/luckperms/sponge/service/LuckPermsSubjectData.java

@@ -376,7 +376,7 @@ public class LuckPermsSubjectData implements LPSubjectData {
 
             toRemove.forEach(makeUnsetConsumer(this.enduring));
 
-            MetaAccumulator metaAccumulator = this.holder.accumulateMeta(null, null, this.service.getPlugin().getContextManager().formContexts(contexts));
+            MetaAccumulator metaAccumulator = this.holder.accumulateMeta(null, this.service.getPlugin().getContextManager().formContexts(contexts));
             int priority = metaAccumulator.getChatMeta(type).keySet().stream().mapToInt(e -> e).max().orElse(0);
             priority += 10;
 

sponge/src/main/resources/luckperms.conf

@@ -128,6 +128,18 @@ apply-sponge-implicit-wildcards=true
 # false, LuckPerms will ignore this data when considering if a player has a permission.
 apply-sponge-default-subjects=true
 
+# The algorithm LuckPerms should use when traversing the "inheritance tree".
+#
+# The valid options are:
+# - breadth-first
+# - depth-first-pre-order
+# - depth-first-post-order
+#
+# See here for information about the differences between each algorithm.
+# - https://en.wikipedia.org/wiki/Breadth-first_search
+# - https://en.wikipedia.org/wiki/Depth-first_search
+inheritance-traversal-algorithm="depth-first-pre-order"
+
 # Define special group weights for this server.
 # Default is just 0.
 group-weight {