requested changes

src/main/java/ch/njol/skript/aliases/AliasesParser.java

@@ -538,7 +538,7 @@ protected Map<String, Variation> parseKeyVariations(String name) {
 			int insertPoint = -1;
 
 			/**
-			 * Tags by their names. All variations can add and overwrite them.
+			 * TagRegistry by their names. All variations can add and overwrite them.
 			 */
 			Map<String, Object> tags = new HashMap<>();
 

src/main/java/ch/njol/skript/aliases/AliasesProvider.java

@@ -45,7 +45,7 @@ public class AliasesProvider {
 	private final Set<Material> materials;
 
 	/**
-	 * Tags are in JSON format. We may need GSON when merging tags
+	 * TagRegistry are in JSON format. We may need GSON when merging tags
 	 * (which might be done if variations are used).
 	 */
 	private final Gson gson;
@@ -89,7 +89,7 @@ public Map<String, Object> parseMojangson(String raw) {
 	/**
 	 * Applies given tags to an item stack.
 	 * @param stack Item stack.
-	 * @param tags Tags.
+	 * @param tags TagRegistry.
 	 * @return Additional flags for the item.
 	 */
 	public int applyTags(ItemStack stack, Map<String, Object> tags) {
@@ -127,7 +127,7 @@ public int applyTags(ItemStack stack, Map<String, Object> tags) {
 	 * Adds an alias to this provider.
 	 * @param name Name of alias without any patterns or variation blocks.
 	 * @param id Id of material.
-	 * @param tags Tags for material.
+	 * @param tags TagRegistry for material.
 	 * @param blockStates Block states.
 	 */
 	public void addAlias(AliasName name, String id, @Nullable Map<String, Object> tags, Map<String, String> blockStates) {

src/main/java/ch/njol/skript/aliases/ItemData.java

@@ -605,7 +605,7 @@ public void deserialize(Fields fields) throws StreamCorruptedException, NotSeria
 
 	/**
 	 * Creates a plain copy of this ItemData. It will have same material,
-	 * amount of 1 and same block values. Tags will also be copied, with
+	 * amount of 1 and same block values. TagRegistry will also be copied, with
 	 * following exceptions:
 	 * <ul>
 	 * <li>Damage: 1.13 tag-damage is only used for actual durability.
@@ -635,7 +635,7 @@ public ItemData aliasCopy() {
 
 	/**
 	 * Applies tags to this item.
-	 * @param tags Tags in Mojang's JSON format.
+	 * @param tags TagRegistry in Mojang's JSON format.
 	 */
 	public void applyTags(String tags) {
 		if (stack == null)

src/main/java/ch/njol/skript/expressions/ExprScoreboardTags.java

@@ -38,7 +38,7 @@
 import ch.njol.util.Kleenean;
 import ch.njol.util.coll.CollectionUtils;
 
-@Name("Scoreboard Tags")
+@Name("Scoreboard TagRegistry")
 @Description({"Scoreboard tags are simple list of texts stored directly in the data of an <a href='classes.html#entity'>entity</a>.",
 		"So this is a Minecraft related thing, not Bukkit, so the tags will not get removed when the server stops. " +
 		"You can visit <a href='https://minecraft.wiki/w/Scoreboard#Tags'>visit Minecraft Wiki</a> for more info.",

src/main/java/ch/njol/skript/util/chat/ChatMessages.java

@@ -229,7 +229,7 @@ else if (c2 == '>')
 					} else {
 						name = tag;
 					}
-					name = name.toLowerCase(Locale.ENGLISH); // Tags are case-insensitive
+					name = name.toLowerCase(Locale.ENGLISH); // TagRegistry are case-insensitive
 
 					boolean tryHex = Utils.HEX_SUPPORTED && name.startsWith("#");
 					ChatColor chatColor = null;

src/main/java/org/skriptlang/skript/bukkit/tags/SkriptTag.java

@@ -11,14 +11,19 @@
 import java.util.HashSet;
 import java.util.Set;
 
+/**
+ * Represents a custom tag created by the Skript user.
+ * Implementation of {@link Tag} with a custom set of contents.
+ * @param <T> The type of the contents.
+ */
 public class SkriptTag<T extends Keyed> implements Tag<T> {
 
 	private final Set<T> contents;
 	private final NamespacedKey key;
 
 	public SkriptTag(NamespacedKey key, Collection<T> contents) {
-		this.contents = new HashSet<>(contents);
 		this.key = key;
+		this.contents = new HashSet<>(contents);
 	}
 
 	@Override

src/main/java/org/skriptlang/skript/bukkit/tags/TagModule.java

@@ -19,8 +19,6 @@
 import org.jetbrains.annotations.Nullable;
 import org.skriptlang.skript.lang.comparator.Comparators;
 import org.skriptlang.skript.lang.comparator.Relation;
-import org.skriptlang.skript.lang.converter.Converter;
-import org.skriptlang.skript.lang.converter.Converters;
 
 import java.io.IOException;
 
@@ -30,15 +28,13 @@ public class TagModule {
 	public static final boolean PAPER_TAGS_EXIST = Skript.classExists("com.destroystokyo.paper.MaterialTags");
 
 	// tag object
-	public static Tags TAGS;
+	public static TagRegistry TagRegistry;
 
 	public static void load() throws IOException {
 		// abort if no class exists
 		if (!Skript.classExists("org.bukkit.Tag"))
 			return;
 
-		// load classes (todo: replace with registering methods after regitration api
-		Skript.getAddonInstance().loadClasses("org.skriptlang.skript.bukkit", "tags");
 
 		// Classes
 		Classes.registerClass(new ClassInfo<>(Tag.class, "minecrafttag")
@@ -63,14 +59,14 @@ public String toVariableNameString(Tag<?> tag) {
 				}
 			}));
 
+		// load classes (todo: replace with registering methods after registration api
+		Skript.getAddonInstance().loadClasses("org.skriptlang.skript.bukkit", "tags");
+
 		// compare tags by keys, not by object instance.
 		Comparators.registerComparator(Tag.class, Tag.class, (a, b) -> Relation.get(a.getKey().equals(b.getKey())));
 
-		// converter to String
-		Converters.registerConverter(Tag.class, String.class, tag -> tag.getKey().toString(), Converter.NO_LEFT_CHAINING);
-
 		// init tags
-		TAGS = new Tags();
+		TagRegistry = new TagRegistry();
 	}
 
 	/**

src/main/java/org/skriptlang/skript/bukkit/tags/Tags.java → src/main/java/org/skriptlang/skript/bukkit/tags/TagRegistry.java

@@ -27,14 +27,14 @@
 /**
  * A class in charge of storing and handling all the tags Skript can access.
  */
-public class Tags {
+public class TagRegistry {
 
 	private final TagSourceMap tagSourceMap = new TagSourceMap();
 
 	/**
 	 * Each new instance will create a new set of tag sources, in an effort to be reload safe.
 	 */
-	public Tags() {
+	TagRegistry() {
 		tagSourceMap.put(TagType.ITEMS, new BukkitTagSource<>("items", TagType.ITEMS));
 		tagSourceMap.put(TagType.BLOCKS, new BukkitTagSource<>("blocks", TagType.BLOCKS));
 		tagSourceMap.put(TagType.ENTITIES, new BukkitTagSource<>("entity_types", TagType.ENTITIES));
@@ -72,15 +72,15 @@ public Tags() {
 	 * @param origin The origin to filter by.
 	 * @param typeClass The class the tags should be applicable to.
 	 * @param types Tag types to check with. Leaving this empty will check all tag types.
-	 * @return Tags from the given origin and types that apply to the given class.
+	 * @return TagRegistry from the given origin and types that apply to the given class.
 	 * @param <T> see typeClass.
 	 */
 	public <T extends Keyed> Iterable<Tag<T>> getTags(TagOrigin origin, Class<T> typeClass, TagType<?>... types) {
 		List<Iterator<Tag<T>>> tagIterators = new ArrayList<>();
 		if (types == null)
 			types = tagSourceMap.map.keys().toArray(new TagType[0]);
 		for (TagType<?> type : types) {
-			if (type.type() == typeClass) {
+			if (typeClass.isAssignableFrom(type.type())) {
 				//noinspection unchecked
 				Iterator<Tag<T>> iterator = getTags(origin, (TagType<T>) type).iterator();
 				if (iterator.hasNext())
@@ -99,7 +99,7 @@ public <T extends Keyed> Iterable<Tag<T>> getTags(TagOrigin origin, Class<T> typ
 	 * Gets all the tags of a specific origin that are of a specific type.
 	 * @param origin The origin to filter by.
 	 * @param type The type of tags to get.
-	 * @return Tags from the given origin that are of the given type.
+	 * @return TagRegistry from the given origin that are of the given type.
 	 * @param <T> The class these tags apply to.
 	 */
 	public <T extends Keyed> Iterable<Tag<T>> getTags(TagOrigin origin, TagType<T> type) {
@@ -114,21 +114,16 @@ public <T extends Keyed> Iterable<Tag<T>> getTags(TagOrigin origin, TagType<T> t
 				return new Iterator<>() {
 					//<editor-fold desc="iterator over tagSources, returning each individual tag">
 					private Iterator<Tag<T>> currentTagIter = tagSources.next().getAllTags().iterator();
-					private Iterator<Tag<T>> nextTagIter;
 
 					@Override
 					public boolean hasNext() {
 						// does the current source have more tags
 						if (currentTagIter.hasNext())
 							return true;
-						// is there another source in the pipeline? if so, check it.
-						if (nextTagIter != null)
-							return nextTagIter.hasNext();
-						// if there's no known next source, check if have one.
-						// if we do, mark it as the next source.
+						// if we have another tag source, mark it as the next source.
 						if (tagSources.hasNext()) {
-							nextTagIter = tagSources.next().getAllTags().iterator();
-							return nextTagIter.hasNext();
+							currentTagIter = tagSources.next().getAllTags().iterator();
+							return currentTagIter.hasNext();
 						}
 						return false;
 					}
@@ -138,12 +133,6 @@ public Tag<T> next() {
 						// if current source has more, get more.
 						if (currentTagIter.hasNext())
 							return currentTagIter.next();
-						// if current source is dry, switch to using the next source
-						if (nextTagIter != null && nextTagIter.hasNext()) {
-							currentTagIter = nextTagIter;
-							nextTagIter = null;
-							return currentTagIter.next();
-						}
 						throw new IllegalStateException("Called next without calling hasNext to set the next tag iterator.");
 					}
 					//</editor-fold>
@@ -158,7 +147,7 @@ public Tag<T> next() {
 	 * @param origin The origin to filter by.
 	 * @param type The type of tags to get.
 	 * @param predicate A predicate to filter the tags with.
-	 * @return Tags from the given origin that are of the given type and that pass the filter.
+	 * @return TagRegistry from the given origin that are of the given type and that pass the filter.
 	 * @param <T> The class these tags apply to.
 	 */
 	public <T extends Keyed> Iterable<Tag<T>> getMatchingTags(TagOrigin origin, TagType<T> type, Predicate<Tag<T>> predicate) {

src/main/java/org/skriptlang/skript/bukkit/tags/TagType.java

@@ -44,9 +44,7 @@ public class TagType<T extends Keyed> {
 	 * @param type The class this tag type applies to.
 	 */
 	public TagType(String pattern, Class<T> type) {
-		this.pattern = pattern;
-		this.type = type;
-		this.toString = pattern;
+		this(pattern, pattern, type);
 	}
 
 	/**
@@ -77,7 +75,7 @@ public String toString() {
 	 * Adds types to the registered tag types.
 	 * @param type The types to add.
 	 */
-	private static void addType(TagType<?>... type) {
+	public static void addType(TagType<?>... type) {
 		REGISTERED_TAG_TYPES.addAll(List.of(type));
 	}
 
@@ -120,6 +118,7 @@ private static void addType(TagType<?>... type) {
 	public static @NotNull String getFullPattern() {
 		return getFullPattern(false);
 	}
+
 	/**
 	 * @param required whether the choice should be optional or required.
 	 * @return Returns a choice pattern for use in Skript patterns. Contains parse marks.

src/main/java/org/skriptlang/skript/bukkit/tags/elements/CondIsTagged.java

@@ -59,8 +59,8 @@ public boolean check(Event event) {
  		return elements.check(event, element -> {
 			boolean isAny = (element instanceof ItemType itemType && !itemType.isAll());
 			Keyed[] values = TagModule.getKeyed(element);
-			 if (values == null)
-				 return false;
+			if (values == null)
+				return false;
 
 			for (Tag<Keyed> tag : tags) {
 				 if (isTagged(tag, values, !isAny)) {

src/main/java/org/skriptlang/skript/bukkit/tags/elements/EffRegisterTag.java

@@ -42,7 +42,7 @@
 	"include the characters A to Z, 0 to 9, and '/', '.', '_', and '-'. Otherwise, the tag will not register.",
 	"",
 	"Please note that two tags can share a name if they are of different types. Registering a new tag of the same " +
-	"name and type will overwrite the existing tag. Tags will reset on server shutdown."
+	"name and type will overwrite the existing tag. TagRegistry will reset on server shutdown."
 })
 @Examples({
 	"register a new custom entity tag named \"fish\" using cod, salmon, tropical fish, and pufferfish",
@@ -61,7 +61,7 @@ public class EffRegisterTag extends Effect {
 
 	static {
 		Skript.registerEffect(EffRegisterTag.class,
-				"register [a[n]] [new] [custom] " + TagType.getFullPattern(true) +
+				"register [a[n]] [custom] " + TagType.getFullPattern(true) +
 					" tag named %string% (containing|using) %entitydatas/itemtypes%");
 	}
 
@@ -74,9 +74,7 @@ public boolean init(Expression<?>[] expressions, int matchedPattern, Kleenean is
 		//noinspection unchecked
 		name = (Expression<String>) expressions[0];
 		if (name instanceof Literal<String> literal) {
-			String key = literal.getSingle();
-			if (key.startsWith("skript:"))
-				key = key.substring(7);
+			String key = removeSkriptNamespace(literal.getSingle());
 			if (!KEY_PATTERN.matcher(key).matches()) {
 				Skript.error("Tag names can only contain the following characters: 'a-z', '0-9', '/', '.', '_', and '-'.");
 				return false;
@@ -94,8 +92,7 @@ protected void execute(Event event) {
 		if (name == null)
 			return;
 
-		if (name.startsWith("skript:"))
-			name = name.substring(7);
+		name = removeSkriptNamespace(name);
 
 		if (!KEY_PATTERN.matcher(name).matches())
 			return;
@@ -121,6 +118,12 @@ protected void execute(Event event) {
 		}
 	}
 
+	private static @NotNull String removeSkriptNamespace(@NotNull String key) {
+		if (key.startsWith("skript:"))
+			key = key.substring(7);
+		return key;
+	}
+
 	@Contract("_, _ -> new")
 	private @NotNull Tag<Material> getMaterialTag(NamespacedKey key, Object @NotNull [] contents) {
 		ThreadLocalRandom random = ThreadLocalRandom.current();
@@ -132,7 +135,8 @@ protected void execute(Event event) {
 				tagContents.add((Material) values[random.nextInt(0, values.length)]);
 			} else {
 				for (Keyed value : values) {
-					tagContents.add((Material) value);
+					if (value instanceof Material material)
+						tagContents.add(material);
 				}
 			}
 		}
@@ -144,7 +148,8 @@ protected void execute(Event event) {
 		List<EntityType> tagContents = new ArrayList<>();
 		for (Object object : contents) {
 			for (Keyed value : TagModule.getKeyed(object)) {
-				tagContents.add((EntityType) value);
+				if (value instanceof EntityType entityType)
+					tagContents.add(entityType);
 			}
 		}
 		return new SkriptTag<>(key, tagContents);
@@ -155,4 +160,5 @@ public String toString(@Nullable Event event, boolean debug) {
 		return "register a new " + type.toString() + " tag named " + name.toString(event, debug) + " containing " +
 				contents.toString(event, debug);
 	}
+
 }

src/main/java/org/skriptlang/skript/bukkit/tags/elements/ExprTag.java

@@ -28,7 +28,7 @@
 @Name("Tag")
 @Description({
 		"Represents a tag which can be used to classify items, blocks, or entities.",
-		"Tags are composed of a value and an optional namespace: \"minecraft:oak_logs\".",
+		"TagRegistry are composed of a value and an optional namespace: \"minecraft:oak_logs\".",
 		"If you omit the namespace, one will be provided for you, depending on what kind of tag you're using. " +
 		"For example, `tag \"doors\"` will be the tag \"minecraft:doors\", " +
 		"while `paper tag \"doors\"` will be \"paper:doors\".",
@@ -97,7 +97,7 @@ public boolean init(Expression<?>[] expressions, int matchedPattern, Kleenean is
 
 			Tag<?> tag;
 			for (TagType<?> type : types) {
-				tag = TagModule.TAGS.getTag(origin, type, key);
+				tag = TagModule.TagRegistry.getTag(origin, type, key);
 				if (tag != null
 					// ensures that only datapack/minecraft tags are sent when specifically requested
 					&& (origin != TagOrigin.BUKKIT || (datapackOnly ^ tag.getKey().getNamespace().equals("minecraft")))

src/main/java/org/skriptlang/skript/bukkit/tags/elements/ExprTagContents.java

@@ -24,7 +24,7 @@
 
 import java.util.Objects;
 
-@Name("Tags Contents")
+@Name("TagRegistry Contents")
 @Description({
 		"Returns all the values that a tag contains.",
 		"For item and block tags, this will return items. For entity tags, " +