add test

Author: SBOne-Kenobi

Diff for: utbot-framework-test/src/test/kotlin/org/utbot/examples/casts/InstanceOfExampleTest.kt

@@ -404,6 +404,16 @@ internal class InstanceOfExampleTest : UtValueTestCaseChecker(
         )
     }
 
+    @Test
+    fun testInstanceOfString() {
+        check(
+            InstanceOfExample::instanceOfString,
+            eq(2),
+            { cs, r -> cs == null && r == Unit },
+            { cs, r -> cs is String && r == null }
+        )
+    }
+
 
     private inline fun <reified T : Any> Any?.isInstanceOfArray() =
         (this as? Array<*>)?.run { T::class.java.isAssignableFrom(this::class.java.componentType) } == true

Diff for: utbot-sample/src/main/java/org/utbot/examples/casts/InstanceOfExample.java

@@ -322,4 +322,10 @@ public Object[] instanceOfObjectArray(Object[] array) {
 
         return array;
     }
+
+    public void instanceOfString(CharSequence cs) {
+        if (cs instanceof String) {
+            throw new IllegalStateException("CharSequence must not be a String");
+        }
+    }
 }