IDEA-203812 bad code green: switch expression does not have any case clauses

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightUtil.java

@@ -1996,7 +1996,7 @@ public class HighlightUtil extends HighlightUtilBase {
       Set<String> missingConstants = new HashSet<>();
       boolean exhaustive = hasDefaultCase;
       if (!exhaustive) {
-        if (selectorType instanceof PsiClassType) {
+        if (!values.isEmpty() && selectorType instanceof PsiClassType) {
           PsiClass type = ((PsiClassType)selectorType).resolve();
           if (type != null && type.isEnum()) {
             for (PsiField field : type.getFields()) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting12/SwitchExpressions.java

@@ -58,4 +58,10 @@ class SwitchExpressions {
       });
     }
   }
+  
+  enum Empty {}
+  
+  boolean testEmpty(Empty e) {
+    return switch (<error descr="'switch' expression does not have any case clauses">e</error>) {};
+  }
 }