RemoveUnusedLocalVariables fails inside case blocks (test)

src/main/java/org/openrewrite/staticanalysis/RemoveUnusedLocalVariables.java

@@ -114,6 +114,8 @@ public J.VariableDeclarations.NamedVariable visitVariable(J.VariableDeclarations
                     parent instanceof J.MethodDeclaration ||
                     // skip if defined in an enhanced or standard for loop, since there isn't much we can do about the semantics at that point
                     parent instanceof J.ForLoop.Control || parent instanceof J.ForEachLoop.Control ||
+                    // skip if defined in a switch case
+                    parent instanceof J.Case ||
                     // skip if defined in a try's catch clause as an Exception variable declaration
                     parent instanceof J.Try.Resource || parent instanceof J.Try.Catch || parent instanceof J.MultiCatch ||
                     // skip if defined as a parameter to a lambda expression

src/test/java/org/openrewrite/staticanalysis/RemoveUnusedLocalVariablesTest.java

@@ -1017,6 +1017,7 @@ fun foo() {
     @Test
     void retainJavaUnusedLocalVariableWithNewClass() {
         rewriteRun(
+          //language=java
           java(
             """
               class A {}
@@ -1030,6 +1031,41 @@ void foo() {
         );
     }
 
+    @Test
+    @Issue("https://github.com/openrewrite/rewrite-static-analysis/issues/152")
+    void retainUnusedInsideCase() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              class Test {
+                  static void method() {
+                      int x = 10;
+                      char y = 20;
+                      switch (x) {
+                          case 10:
+                              byte unused;
+                              break;
+                      }
+                  }
+              }
+              """,
+            """
+              class Test {
+                  static void method() {
+                      int x = 10;
+                      switch (x) {
+                          case 10:
+                              byte unused;
+                              break;
+                      }
+                  }
+              }
+              """
+          )
+        );
+    }
+
     @Nested
     class Kotlin {
 
@@ -1053,12 +1089,14 @@ fun foo() {
         @ExpectedToFail("Not yet implemented")
         void retainUnusedLocalVariableConst() {
             rewriteRun(
+              //language=kotlin
               kotlin(
                 """
                   package constants
                   const val FOO = "bar"
                   """
               ),
+              //language=kotlin
               kotlin(
                 """
                   package config