Add/change comments

api/src/main/java/com/viaversion/viaversion/api/data/MappingDataBase.java

@@ -150,7 +150,7 @@ public class MappingDataBase implements MappingData {
         return new IntArrayMappings(oldMappings.getAsJsonObject(key), newMappings.getAsJsonObject(key), diff);
     }
 
-    protected JsonObject loadDiffFile() {
+    protected @Nullable JsonObject loadDiffFile() {
         return MappingDataLoader.loadData("mappingdiff-" + oldVersion + "to" + newVersion + ".json");
     }
 

build.gradle.kts

@@ -32,8 +32,9 @@ subprojects {
         else -> plugins.apply("via.standard-conventions")
     }
 
+    // Note: If manually starting tests doesn't work for you in IJ, change 'Gradle -> Run Tests Using' to 'IntelliJ IDEA'
     dependencies {
-        // Note: If manually starting tests doesn't work for you in IJ, change 'Gradle -> Run Tests Using' to 'IntelliJ IDEA'
+        // The alternative to this long boi is writing "testImplementation", including the quotes
         TEST_IMPLEMENTATION_CONFIGURATION_NAME(rootProject.libs.netty)
         TEST_IMPLEMENTATION_CONFIGURATION_NAME(rootProject.libs.guava)
         TEST_IMPLEMENTATION_CONFIGURATION_NAME(rootProject.libs.bundles.junit)

common/src/main/java/com/viaversion/viaversion/rewriter/EntityRewriter.java

@@ -73,7 +73,6 @@ public abstract class EntityRewriter<T extends Protocol> extends RewriterBase<T>
      * Returns a meta filter builder.
      * <p>
      * Calling {@link MetaFilter.Builder#register()} will automatically register the filter on this rewriter.
-     * Don't forget to call {@link MetaFilter.Builder#register()}.
      *
      * @return meta filter builder
      */

common/src/main/java/com/viaversion/viaversion/rewriter/meta/MetaFilter.java

@@ -84,11 +84,14 @@ public class MetaFilter {
      * @return whether the meta should be filtered
      */
     public boolean isFiltered(@Nullable EntityType type, Metadata metadata) {
-        // First check if the filter has no type or the type is equal or part of the filtered parent types
-        // Applicable if no specific index is filtered or the indexes are equal
-        return (this.type == null
-                || type != null && (this.filterFamily ? type.isOrHasParent(this.type) : this.type == type))
-                && (this.index == -1 || metadata.id() == this.index);
+        // Check if no specific index is filtered or the indexes are equal
+        // Then check if the filter has no entity type or the type is equal to or part of the filtered parent type
+        return (this.index == -1 || metadata.id() == this.index)
+                && (this.type == null || matchesType(type));
+    }
+
+    private boolean matchesType(@Nullable EntityType type) {
+        return type != null && (this.filterFamily ? type.isOrHasParent(this.type) : this.type == type);
     }
 
     @Override
@@ -162,6 +165,7 @@ public class MetaFilter {
          * Should always be called last.
          *
          * @param handler metadata handler
+         * @throws IllegalArgumentException if a handler has already been set
          */
         public void handler(MetaHandler handler) {
             Preconditions.checkArgument(this.handler == null);

common/src/main/java/com/viaversion/viaversion/rewriter/meta/MetaHandlerEvent.java

@@ -65,14 +65,6 @@ public interface MetaHandlerEvent {
         meta().setId(index);
     }
 
-    /**
-     * Returns the metadata by the given index if present.
-     *
-     * @param index metadata index
-     * @return metadata by index if present
-     */
-    @Nullable Metadata getMetaByIndex(int index);
-
     /**
      * Returns the metadata.
      *
@@ -92,10 +84,20 @@ public interface MetaHandlerEvent {
      */
     boolean cancelled();
 
+    /**
+     * Returns metadata by the given index if present.
+     *
+     * @param index metadata index
+     * @return metadata if present, else null
+     */
+    @Nullable Metadata metaAtIndex(int index);
+
     /**
      * Returns an immutable metadata view.
+     * This list is not sorted or indexed by the actual metadata indexes.
      *
      * @return immutable metadata list
+     * @see #metaAtIndex(int)
      * @see #cancel()
      * @see #createExtraMeta(Metadata)
      */

common/src/main/java/com/viaversion/viaversion/rewriter/meta/MetaHandlerEventImpl.java

@@ -44,16 +44,6 @@ public class MetaHandlerEventImpl implements MetaHandlerEvent {
         this.metadataList = metadataList;
     }
 
-    @Override
-    public @Nullable Metadata getMetaByIndex(int index) {
-        for (Metadata meta : metadataList) {
-            if (index == meta.id()) {
-                return meta;
-            }
-        }
-        return null;
-    }
-
     @Override
     public UserConnection user() {
         return connection;
@@ -84,6 +74,16 @@ public class MetaHandlerEventImpl implements MetaHandlerEvent {
         return cancel;
     }
 
+    @Override
+    public @Nullable Metadata metaAtIndex(int index) {
+        for (Metadata meta : metadataList) {
+            if (index == meta.id()) {
+                return meta;
+            }
+        }
+        return null;
+    }
+
     @Override
     public List<Metadata> metadataList() {
         return Collections.unmodifiableList(metadataList);