test: add tests for isValidName helper

Signed-off-by: vikhy-aws <191836418+vikhy-aws@users.noreply.github.com>

src/test/kotlin/org/opensearch/commons/utils/ValidationHelpers.kt

@@ -0,0 +1,57 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.commons.utils
+
+import org.junit.jupiter.api.Assertions.assertFalse
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+
+class ValidationHelpers {
+    @Test
+    fun `test valid names`() {
+        /*  Start with letter or underscore
+            Followed by letters, numbers, underscore or hyphen
+            Total length between 4 and 50 characters */
+
+        assertTrue(isValidName("valid"))
+        assertTrue(isValidName("Valid_name"))
+        assertTrue(isValidName("valid_name_123"))
+        assertTrue(isValidName("_validName"))
+        assertTrue(isValidName("valid_name-123"))
+        assertTrue(isValidName("_123_valid_name"))
+
+        // Boundary value tests
+        assertTrue(isValidName("qwer"))
+        assertTrue(isValidName("q".repeat(50)))
+        assertTrue(isValidName("____"))
+        assertTrue(isValidName("a-b-"))
+    }
+
+    @Test
+    fun `test invalid names`() {
+        // Invalid starting characters
+        assertFalse(isValidName("123name"))
+        assertFalse(isValidName("-name"))
+        assertFalse(isValidName("1name"))
+
+        // Should not have invalid characters
+        assertFalse(isValidName("invalid@name"))
+        assertFalse(isValidName("invalid name"))
+        assertFalse(isValidName("invalid#name"))
+        assertFalse(isValidName("invalid.name"))
+        assertFalse(isValidName("        "))
+
+        // Should not allow special characters other than _ and -
+        assertFalse(isValidName("name!"))
+        assertFalse(isValidName("name*"))
+        assertFalse(isValidName("name$"))
+        assertFalse(isValidName("name%"))
+
+        // Boundary value tests
+        assertFalse(isValidName("abc"))
+        assertFalse(isValidName("a".repeat(51)))
+    }
+}