Make annotations data a bit nicer to use (#1391)

* Make annotations data a bit nicer to use

* Add copy constructors

src/main/java/net/fabricmc/loom/configuration/providers/mappings/extras/annotations/AnnotationsData.java

@@ -27,11 +27,13 @@ package net.fabricmc.loom.configuration.providers.mappings.extras.annotations;
 import java.io.IOException;
 import java.io.Reader;
 import java.lang.reflect.Type;
+import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.function.Function;
+import java.util.function.UnaryOperator;
 
 import com.google.gson.FieldNamingPolicy;
 import com.google.gson.Gson;
@@ -69,6 +71,14 @@ public record AnnotationsData(Map<String, ClassAnnotationData> classes, String n
 		}
 	}
 
+	public AnnotationsData(String namespace) {
+		this(new LinkedHashMap<>(), namespace);
+	}
+
+	public AnnotationsData(AnnotationsData other) {
+		this(copyMap(other.classes, ClassAnnotationData::new), other.namespace);
+	}
+
 	public static AnnotationsData read(Reader reader) {
 		JsonObject json = GSON.fromJson(reader, JsonObject.class);
 		checkVersion(json);
@@ -118,6 +128,36 @@ public record AnnotationsData(Map<String, ClassAnnotationData> classes, String n
 		return result;
 	}
 
+	static <K, V> Map<K, V> copyMap(Map<K, V> map, UnaryOperator<V> valueCopier) {
+		Map<K, V> result = LinkedHashMap.newLinkedHashMap(map.size());
+		map.forEach((key, value) -> result.put(key, valueCopier.apply(value)));
+		return result;
+	}
+
+	static List<AnnotationNode> copyAnnotations(List<AnnotationNode> annotations) {
+		List<AnnotationNode> result = new ArrayList<>(annotations.size());
+
+		for (AnnotationNode annotation : annotations) {
+			AnnotationNode newAnnotation = new AnnotationNode(annotation.desc);
+			annotation.accept(newAnnotation);
+			result.add(newAnnotation);
+		}
+
+		return result;
+	}
+
+	static List<TypeAnnotationNode> copyTypeAnnotations(List<TypeAnnotationNode> annotations) {
+		List<TypeAnnotationNode> result = new ArrayList<>(annotations.size());
+
+		for (TypeAnnotationNode annotation : annotations) {
+			TypeAnnotationNode newAnnotation = new TypeAnnotationNode(annotation.typeRef, annotation.typePath, annotation.desc);
+			annotation.accept(newAnnotation);
+			result.add(newAnnotation);
+		}
+
+		return result;
+	}
+
 	public AnnotationsData merge(AnnotationsData other) {
 		if (!namespace.equals(other.namespace)) {
 			throw new IllegalArgumentException("Cannot merge annotations from namespace " + other.namespace + " into annotations from namespace " + this.namespace);

src/main/java/net/fabricmc/loom/configuration/providers/mappings/extras/annotations/BaseAnnotationData.java

@@ -0,0 +1,38 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2025 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.providers.mappings.extras.annotations;
+
+import java.util.List;
+import java.util.Set;
+
+import org.objectweb.asm.tree.AnnotationNode;
+import org.objectweb.asm.tree.TypeAnnotationNode;
+
+public interface BaseAnnotationData {
+	Set<String> annotationsToRemove();
+	List<AnnotationNode> annotationsToAdd();
+	Set<TypeAnnotationKey> typeAnnotationsToRemove();
+	List<TypeAnnotationNode> typeAnnotationsToAdd();
+}

src/main/java/net/fabricmc/loom/configuration/providers/mappings/extras/annotations/ClassAnnotationData.java

@@ -52,7 +52,7 @@ public record ClassAnnotationData(
 		List<TypeAnnotationNode> typeAnnotationsToAdd,
 		Map<String, GenericAnnotationData> fields,
 		Map<String, MethodAnnotationData> methods
-) {
+) implements BaseAnnotationData {
 	public ClassAnnotationData {
 		if (annotationsToRemove == null) {
 			annotationsToRemove = new LinkedHashSet<>();
@@ -79,6 +79,21 @@ public record ClassAnnotationData(
 		}
 	}
 
+	public ClassAnnotationData() {
+		this(new LinkedHashSet<>(), new ArrayList<>(), new LinkedHashSet<>(), new ArrayList<>(), new LinkedHashMap<>(), new LinkedHashMap<>());
+	}
+
+	public ClassAnnotationData(ClassAnnotationData other) {
+		this(
+				new LinkedHashSet<>(other.annotationsToRemove),
+				AnnotationsData.copyAnnotations(other.annotationsToAdd),
+				new LinkedHashSet<>(other.typeAnnotationsToRemove),
+				AnnotationsData.copyTypeAnnotations(other.typeAnnotationsToAdd),
+				AnnotationsData.copyMap(other.fields, GenericAnnotationData::new),
+				AnnotationsData.copyMap(other.methods, MethodAnnotationData::new)
+		);
+	}
+
 	ClassAnnotationData merge(ClassAnnotationData other) {
 		Set<String> newAnnotationsToRemove = new LinkedHashSet<>(annotationsToRemove);
 		newAnnotationsToRemove.addAll(other.annotationsToRemove);

src/main/java/net/fabricmc/loom/configuration/providers/mappings/extras/annotations/GenericAnnotationData.java

@@ -46,7 +46,7 @@ public record GenericAnnotationData(
 		Set<TypeAnnotationKey> typeAnnotationsToRemove,
 		@SerializedName("type_add")
 		List<TypeAnnotationNode> typeAnnotationsToAdd
-) {
+) implements BaseAnnotationData {
 	public GenericAnnotationData {
 		if (annotationsToRemove == null) {
 			annotationsToRemove = new LinkedHashSet<>();
@@ -65,6 +65,19 @@ public record GenericAnnotationData(
 		}
 	}
 
+	public GenericAnnotationData() {
+		this(new LinkedHashSet<>(), new ArrayList<>(), new LinkedHashSet<>(), new ArrayList<>());
+	}
+
+	public GenericAnnotationData(GenericAnnotationData other) {
+		this(
+				new LinkedHashSet<>(other.annotationsToRemove),
+				AnnotationsData.copyAnnotations(other.annotationsToAdd),
+				new LinkedHashSet<>(other.typeAnnotationsToRemove),
+				AnnotationsData.copyTypeAnnotations(other.typeAnnotationsToAdd)
+		);
+	}
+
 	GenericAnnotationData merge(GenericAnnotationData other) {
 		Set<String> newAnnotationToRemove = new LinkedHashSet<>(annotationsToRemove);
 		newAnnotationToRemove.addAll(other.annotationsToRemove);

src/main/java/net/fabricmc/loom/configuration/providers/mappings/extras/annotations/MethodAnnotationData.java

@@ -49,7 +49,7 @@ public record MethodAnnotationData(
 		@SerializedName("type_add")
 		List<TypeAnnotationNode> typeAnnotationsToAdd,
 		Map<Integer, GenericAnnotationData> parameters
-) {
+) implements BaseAnnotationData {
 	public MethodAnnotationData {
 		if (annotationsToRemove == null) {
 			annotationsToRemove = new LinkedHashSet<>();
@@ -72,6 +72,20 @@ public record MethodAnnotationData(
 		}
 	}
 
+	public MethodAnnotationData() {
+		this(new LinkedHashSet<>(), new ArrayList<>(), new LinkedHashSet<>(), new ArrayList<>(), new LinkedHashMap<>());
+	}
+
+	public MethodAnnotationData(MethodAnnotationData other) {
+		this(
+				new LinkedHashSet<>(other.annotationsToRemove),
+				AnnotationsData.copyAnnotations(other.annotationsToAdd),
+				new LinkedHashSet<>(other.typeAnnotationsToRemove),
+				AnnotationsData.copyTypeAnnotations(other.typeAnnotationsToAdd),
+				AnnotationsData.copyMap(other.parameters, GenericAnnotationData::new)
+		);
+	}
+
 	MethodAnnotationData merge(MethodAnnotationData other) {
 		Set<String> newAnnotationsToRemove = new LinkedHashSet<>(annotationsToRemove);
 		newAnnotationsToRemove.addAll(other.annotationsToRemove);