Fix: issue 4579 Switch expr and var incompatibility

javaparser-core-testing/src/test/java/com/github/javaparser/ast/validator/VarValidatorTest.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2007-2010 Júlio Vilmar Gesser.
+ * Copyright (C) 2011, 2013-2024 The JavaParser Team.
+ *
+ * This file is part of JavaParser.
+ *
+ * JavaParser can be used either under the terms of
+ * a) the GNU Lesser General Public License as published by
+ *     the Free Software Foundation, either version 3 of the License, or
+ *     (at your option) any later version.
+ * b) the terms of the Apache License
+ *
+ * You should have received a copy of both licenses in LICENCE.LGPL and
+ * LICENCE.APACHE. Please refer to those files for details.
+ *
+ * JavaParser is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ */
+
+package com.github.javaparser.ast.validator;
+
+import static com.github.javaparser.ParseStart.STATEMENT;
+import static com.github.javaparser.Providers.provider;
+import static com.github.javaparser.utils.TestUtils.assertNoProblems;
+
+import com.github.javaparser.JavaParser;
+import com.github.javaparser.ParseResult;
+import com.github.javaparser.ParserConfiguration;
+import com.github.javaparser.ParserConfiguration.LanguageLevel;
+import com.github.javaparser.ast.stmt.Statement;
+import org.junit.jupiter.api.Test;
+
+class VarValidatorTest {
+    public static final JavaParser javaParser =
+            new JavaParser(new ParserConfiguration().setLanguageLevel(LanguageLevel.BLEEDING_EDGE));
+
+    @Test
+    void typePatternExpr() {
+        ParseResult<Statement> result = javaParser.parse(
+                STATEMENT, provider("switch (shape) {\n" + "  case Circle(var radius) -> { } \n" + "}"));
+
+        assertNoProblems(result);
+    }
+}

javaparser-core/src/main/java/com/github/javaparser/ast/validator/language_level_validations/chunks/VarValidator.java

@@ -23,10 +23,7 @@
 import com.github.javaparser.ast.Node;
 import com.github.javaparser.ast.body.Parameter;
 import com.github.javaparser.ast.body.VariableDeclarator;
-import com.github.javaparser.ast.expr.ArrayInitializerExpr;
-import com.github.javaparser.ast.expr.LambdaExpr;
-import com.github.javaparser.ast.expr.NullLiteralExpr;
-import com.github.javaparser.ast.expr.VariableDeclarationExpr;
+import com.github.javaparser.ast.expr.*;
 import com.github.javaparser.ast.stmt.ExpressionStmt;
 import com.github.javaparser.ast.stmt.ForEachStmt;
 import com.github.javaparser.ast.stmt.ForStmt;
@@ -46,6 +43,16 @@ public VarValidator(boolean varAllowedInLambdaParameters) {
 
     @Override
     public void accept(VarType node, ProblemReporter reporter) {
+        // Allowed in type pattern expression. For example
+        // record Name(String fName, String lName, String mName) {};
+        // Name host = new Name("William", "Michael", "Korando");
+        // String printName = switch(person){
+        //   case Name(var fName, var lName, var mName) -> lName + ", " + fName + " " + mName;
+        // };
+        if (node.hasParentNode() && node.getParentNode().get() instanceof TypePatternExpr) {
+            return;
+        }
+
         // All allowed locations are within a VariableDeclaration inside a VariableDeclarationExpr inside something
         // else.
         Optional<VariableDeclarator> variableDeclarator = node.findAncestor(VariableDeclarator.class);