[java-highlighting] IDEA-324474 Highlight unreachable statement for exhaustive switch. Tests

GitOrigin-RevId: 97f525a579bd45c6863a6662142f26193e7e2429

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlightingPatternsInSwitch/ReachabilityStatement.java

@@ -0,0 +1,48 @@
+public class Switches {
+
+  enum E {
+    A, B
+  }
+
+  int testReachability(E e) {
+    switch (e) {
+      case E d when d == E.A:
+        return 1;
+      case A:
+        return -1;
+      case B:
+        return -2;
+    }
+    <error descr="Unreachable statement">return</error> 1;
+  }
+
+  sealed interface T {
+  }
+
+  final class T1 implements T {
+  }
+
+  final class T2 implements T {
+  }
+
+  void testReachability2(T i) {
+    switch (i) {
+      case T1 f:
+        throw new RuntimeException();
+      case T2 s:
+        throw new RuntimeException();
+    }
+    <error descr="Unreachable statement">System.out.println();</error>
+  }
+
+  class Reachability2{
+    sealed interface T{}
+    final class T1 implements T{}
+
+    int test(T t) {
+      switch (t) {
+        case T1  t1: return 2;
+      }
+    }
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInsight/daemon/LightPatternsForSwitchHighlightingTest.java

@@ -114,6 +114,9 @@ public class LightPatternsForSwitchHighlightingTest extends LightJavaCodeInsight
   public void testReachability() {
     doTest();
   }
+  public void testReachabilityStatement() {
+    doTest();
+  }
 
   public void testEffectivelyFinal() {
     IdeaTestUtil.withLevel(getModule(), LanguageLevel.JDK_20_PREVIEW, this::doTest);