[jdk22] Adds support for unnamed variables (JEP 456)

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;
+		};
+	}
+}