suppress inspection for switch backward migration when not -> used: IDEA-204207

java/java-impl/src/com/intellij/codeInspection/EnhancedSwitchBackwardMigrationInspection.java

@@ -34,6 +34,7 @@ public class EnhancedSwitchBackwardMigrationInspection extends AbstractBaseJavaL
     return new JavaElementVisitor() {
       @Override
       public void visitSwitchExpression(PsiSwitchExpression expression) {
+        if (!SwitchUtils.isRuleFormatSwitch(expression)) return;
         if (findReplacer(expression) == null) return;
         String message = InspectionsBundle.message("inspection.switch.expression.backward.expression.migration.inspection.name");
         holder.registerProblem(expression.getFirstChild(), message, new ReplaceWithOldStyleSwitchFix());
@@ -41,8 +42,8 @@ public class EnhancedSwitchBackwardMigrationInspection extends AbstractBaseJavaL
 
       @Override
       public void visitSwitchStatement(PsiSwitchStatement statement) {
-        if (findReplacer(statement) == null) return;
         if (!SwitchUtils.isRuleFormatSwitch(statement)) return;
+        if (findReplacer(statement) == null) return;
         String message = InspectionsBundle.message("inspection.switch.expression.backward.statement.migration.inspection.name");
         holder.registerProblem(statement.getFirstChild(), message, new ReplaceWithOldStyleSwitchFix());
       }

java/java-tests/testData/inspection/switchExpressionBackwardMigration/beforeSwitchOldStyle.java

@@ -0,0 +1,13 @@
+// "Replace with old style 'switch' statement" "false"
+import java.util.*;
+
+class SwitchExpressionMigration {
+  int foo(int n) {
+    return switch<caret> (n) {
+      case 1:
+        break 1;
+      default:
+        break 0;
+    };
+  }
+}