Store all accumulated meta values in MetaCache

api/src/main/java/me/lucko/luckperms/api/caching/MetaData.java

@@ -25,6 +25,8 @@
 
 package me.lucko.luckperms.api.caching;
 
+import com.google.common.collect.ListMultimap;
+
 import me.lucko.luckperms.api.metastacking.MetaStackDefinition;
 
 import java.util.Map;
@@ -38,7 +40,24 @@ import java.util.SortedMap;
 public interface MetaData {
 
     /**
-     * Gets an immutable copy of the meta this user has
+     * Gets an immutable copy of the meta this user has.
+     *
+     * <p>A list multimap is used because when inherited values are included, each key can be
+     * mapped to multiple values.</p>
+     *
+     * <p>The first value to be accumulated (and used to represent the key in {@link #getMeta()} is at index 0
+     * in the list. Any additional values are stored in order of accumulation.</p>
+     *
+     * @return an immutable multimap of meta
+     * @since 3.3
+     */
+    ListMultimap<String, String> getMetaMultimap();
+
+    /**
+     * Gets an immutable copy of the meta this user has.
+     *
+     * <p>This map is formed by taking the entries in {@link #getMetaMultimap()}, and mapping each key
+     * to the value at index 0 in the corresponding list.</p>
      *
      * @return an immutable map of meta
      */

common/src/main/java/me/lucko/luckperms/common/caching/MetaAccumulator.java

@@ -30,6 +30,9 @@ import lombok.Getter;
 import lombok.NonNull;
 import lombok.ToString;
 
+import com.google.common.collect.ArrayListMultimap;
+import com.google.common.collect.ListMultimap;
+
 import me.lucko.luckperms.api.ChatMetaType;
 import me.lucko.luckperms.api.LocalizedNode;
 import me.lucko.luckperms.common.config.ConfigKeys;
@@ -38,7 +41,6 @@ import me.lucko.luckperms.common.metastacking.MetaStack;
 import me.lucko.luckperms.common.plugin.LuckPermsPlugin;
 
 import java.util.Comparator;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.SortedMap;
 import java.util.TreeMap;
@@ -57,7 +59,7 @@ public class MetaAccumulator {
     }
 
     @Getter(AccessLevel.NONE)
-    private final Map<String, String> meta;
+    private final ListMultimap<String, String> meta;
     private final SortedMap<Integer, String> prefixes;
     private final SortedMap<Integer, String> suffixes;
     private int weight = 0;
@@ -66,7 +68,7 @@ public class MetaAccumulator {
     private final MetaStack suffixStack;
 
     public MetaAccumulator(@NonNull MetaStack prefixStack, @NonNull MetaStack suffixStack) {
-        this.meta = new HashMap<>();
+        this.meta = ArrayListMultimap.create();
         this.prefixes = new TreeMap<>(Comparator.reverseOrder());
         this.suffixes = new TreeMap<>(Comparator.reverseOrder());
         this.prefixStack = prefixStack;
@@ -76,9 +78,7 @@ public class MetaAccumulator {
     public void accumulateNode(LocalizedNode n) {
         if (n.isMeta()) {
             Map.Entry<String, String> entry = n.getMeta();
-            if (!meta.containsKey(entry.getKey())) {
+            meta.put(entry.getKey(), entry.getValue());
-                meta.put(entry.getKey(), entry.getValue());
-            }
         }
 
         if (n.isPrefix()) {
@@ -106,7 +106,7 @@ public class MetaAccumulator {
 
     // We can assume that if this method is being called, this holder is effectively finalized. (it's not going to accumulate more nodes)
     // Therefore, it should be ok to set the weight meta key, if not already present.
-    public Map<String, String> getMeta() {
+    public ListMultimap<String, String> getMeta() {
         if (!this.meta.containsKey("weight") && this.weight != 0) {
             this.meta.put("weight", String.valueOf(this.weight));
         }

common/src/main/java/me/lucko/luckperms/common/caching/MetaCache.java

@@ -25,16 +25,20 @@
 
 package me.lucko.luckperms.common.caching;
 
+import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 
+import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSortedMap;
+import com.google.common.collect.ListMultimap;
 
 import me.lucko.luckperms.api.caching.MetaData;
 import me.lucko.luckperms.api.metastacking.MetaStackDefinition;
 import me.lucko.luckperms.common.metastacking.MetaStack;
 
+import java.util.List;
 import java.util.Map;
 import java.util.SortedMap;
 import java.util.concurrent.locks.ReadWriteLock;
@@ -43,29 +47,38 @@ import java.util.concurrent.locks.ReentrantReadWriteLock;
 /**
  * Holds a user's cached meta for a given context
  */
+@Getter
 @NoArgsConstructor
 public class MetaCache implements MetaData {
+    @Getter(AccessLevel.NONE)
     private final ReadWriteLock lock = new ReentrantReadWriteLock();
 
-    @Getter
+    private ListMultimap<String, String> metaMultimap = ImmutableListMultimap.of();
     private Map<String, String> meta = ImmutableMap.of();
-
-    @Getter
     private SortedMap<Integer, String> prefixes = ImmutableSortedMap.of();
-
-    @Getter
     private SortedMap<Integer, String> suffixes = ImmutableSortedMap.of();
-
-    @Getter
     private MetaStack prefixStack = null;
-
-    @Getter
     private MetaStack suffixStack = null;
 
     public void loadMeta(MetaAccumulator meta) {
         lock.writeLock().lock();
         try {
-            this.meta = ImmutableMap.copyOf(meta.getMeta());
+            this.metaMultimap = ImmutableListMultimap.copyOf(meta.getMeta());
+
+            //noinspection unchecked
+            Map<String, List<String>> metaMap = (Map) this.metaMultimap.asMap();
+            ImmutableMap.Builder<String, String> metaMapBuilder = ImmutableMap.builder();
+
+            for (Map.Entry<String, List<String>> e : metaMap.entrySet()) {
+                if (e.getValue().isEmpty()) {
+                    continue;
+                }
+
+                // take the value which was accumulated first
+                metaMapBuilder.put(e.getKey(), e.getValue().get(0));
+            }
+            this.meta = metaMapBuilder.build();
+
             this.prefixes = ImmutableSortedMap.copyOfSorted(meta.getPrefixes());
             this.suffixes = ImmutableSortedMap.copyOfSorted(meta.getSuffixes());
             this.prefixStack = meta.getPrefixStack();

sponge/src/main/java/me/lucko/luckperms/sponge/model/SpongeGroup.java

@@ -30,6 +30,7 @@ import lombok.Getter;
 import com.github.benmanes.caffeine.cache.Caffeine;
 import com.github.benmanes.caffeine.cache.LoadingCache;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ListMultimap;
 
 import me.lucko.luckperms.api.ChatMetaType;
 import me.lucko.luckperms.api.LocalizedNode;
@@ -54,6 +55,7 @@ import org.spongepowered.api.service.permission.PermissionService;
 
 import co.aikar.timings.Timing;
 
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
@@ -238,8 +240,9 @@ public class SpongeGroup extends Group {
 
         private Optional<String> getMeta(ImmutableContextSet contexts, String key) {
             MetaAccumulator metaAccumulator = parent.accumulateMeta(null, null, ExtractedContexts.generate(plugin.getService().calculateContexts(contexts)));
-            Map<String, String> meta = metaAccumulator.getMeta();
+            ListMultimap<String, String> meta = metaAccumulator.getMeta();
-            return Optional.ofNullable(meta.get(key));
+            List<String> ret = meta.get(key);
+            return ret.isEmpty() ? Optional.empty() : Optional.of(ret.get(0));
         }
     }
 }