diff --git a/core-groovy/src/test/groovy/com/baeldung/strings/ConvertStringToInt.groovy b/core-groovy/src/test/groovy/com/baeldung/strings/ConvertStringToInt.groovy
index 3b73c31596..7a4be4a957 100644
--- a/core-groovy/src/test/groovy/com/baeldung/strings/ConvertStringToInt.groovy
+++ b/core-groovy/src/test/groovy/com/baeldung/strings/ConvertStringToInt.groovy
@@ -96,4 +96,15 @@ class ConvertStringToInt {
         def invalidString = null
         invalidString.toInteger()
     }
+
+    @Test
+    void givenString_whenUsingIsInteger_thenCheckIfCorrectValue() {
+        def invalidString = "123a"
+        def validString = "123"
+        def invalidNum = invalidString?.isInteger() ? invalidString as Integer : false
+        def correctNum = validString?.isInteger() ? validString as Integer : false
+
+        assertEquals(false, invalidNum)
+        assertEquals(123, correctNum)
+    }
 }