Support unnamed variables

src/delombok/lombok/delombok/PrettyPrinter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2016-2021 The Project Lombok Authors.
+ * Copyright (C) 2016-2024 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -263,6 +263,14 @@ private boolean suppress(JCTree tree) {
 		return false;
 	}
 
+	private void print(Name name) {
+		if (name.isEmpty()) {
+			print("_");
+		} else {
+			print(name.toString());
+		}
+	}
+
 	private void print(CharSequence s) {
 		boolean align = needsAlign;
 		if (needsNewLine && !onNewLine) println();
@@ -1722,6 +1730,8 @@ public void visitTypeBoundKind(TypeBoundKind tree) {
 			printPatternCaseLabel(tree);
 		} else if (className.endsWith("$JCRecordPattern")) { // Introduced in JDK19
 			printRecordPattern(tree);
+		} else if (className.endsWith("$JCAnyPattern")) { // Introduced in JDK22
+			print("_");
 		} else {
 			throw new AssertionError("Unhandled tree type: " + tree.getClass() + ": " + tree);
 		}

test/pretty/resource/after/UnnamedVariables.java

@@ -0,0 +1,70 @@
+// version 22:
+import java.util.Arrays;
+import java.util.Scanner;
+import java.util.stream.Stream;
+
+record Box<T>(T content) {
+}
+
+record Pair<T, U>(T first, U second) {
+}
+
+public class UnnamedVariables {
+	void enhancedLoop() {
+		for (String _ : Arrays.asList("")) {
+		}
+	}
+
+	void initializationInForLoop() {
+		for (int i = 0, _ = Integer.MAX_VALUE; i < 10; i++) {
+		}
+	}
+
+	void assignment() {
+		var _ = 1;
+	}
+
+	void catchBlock() {
+		try {
+		} catch (Exception _) {
+		}
+	}
+
+	void tryWithResources() {
+		try (var _ = new Scanner("")) {
+		}
+	}
+
+	void lambda() {
+		Stream.of(1).forEach(_ -> {
+		});
+	}
+
+	Object switchStatement(Object o) {
+		return switch (o) {
+			case String _, Integer _ -> o;
+			case Long _ -> o;
+			default -> o;
+		};
+	}
+
+	void recordPattern(Object o) {
+		if (o instanceof Pair(Box _, Box(Integer _))) {
+		}
+		if (o instanceof Box(String _)) {
+		}
+		if (o instanceof Box(var _)) {
+		}
+		if (o instanceof Box(_)) {
+		}
+	}
+
+	Object recordPatternSwitch(Object o) {
+		return switch (o) {
+			case Box(String _), Box(Integer _) -> o;
+			case Box(Long _) -> o;
+			case Box(_) -> o;
+			default -> o;
+		};
+	}
+}

test/pretty/resource/before/UnnamedVariables.java

@@ -0,0 +1,70 @@
+// version 22:
+import java.util.Arrays;
+import java.util.Scanner;
+import java.util.stream.Stream;
+
+record Box<T>(T content) {
+}
+
+record Pair<T, U>(T first, U second) {
+}
+
+public class UnnamedVariables {
+	void enhancedLoop() {
+		for (String _ : Arrays.asList("")) {
+		}
+	}
+
+	void initializationInForLoop() {
+		for (int i = 0, _ = Integer.MAX_VALUE; i < 10; i++) {
+		}
+	}
+
+	void assignment() {
+		var _ = 1;
+	}
+
+	void catchBlock() {
+		try {
+		} catch (Exception _) {
+		}
+	}
+
+	void tryWithResources() {
+		try (var _ = new Scanner("")) {
+		}
+	}
+
+	void lambda() {
+		Stream.of(1).forEach(_ -> {
+		});
+	}
+
+	Object switchStatement(Object o) {
+		return switch (o) {
+			case String _, Integer _ -> o;
+			case Long _ -> o;
+			default -> o;
+		};
+	}
+
+	void recordPattern(Object o) {
+		if (o instanceof Pair(Box _, Box(Integer _))) {
+		}
+		if (o instanceof Box(String _)) {
+		}
+		if (o instanceof Box(var _)) {
+		}
+		if (o instanceof Box(_)) {
+		}
+	}
+
+	Object recordPatternSwitch(Object o) {
+		return switch (o) {
+			case Box(String _), Box(Integer _) -> o;
+			case Box(Long _) -> o;
+			case Box(_) -> o;
+			default -> o;
+		};
+	}
+}