Compiler reports AssertionError for conditional operator ? : and pattern matching for instanceof

Compiler is reporting AssertionError when pattern matching for instanceof is used in the conditional operator ? :

Sample Code:

public class TestPattern {
 
      public static void main(String[] args) {
 
          Object ax = "";

          boolean result = (ax instanceof String a) ? (ax instanceof String a) : (! (ax instanceof String a));
 
          System.out.println("result = " + result);

      }
 }

Result: AssertionError

Expected result: result = true


Compiler log is attached below: