diff --git a/src/cpl_core/utils/string.py b/src/cpl_core/utils/string.py
index cfeea681..31c0c483 100644
--- a/src/cpl_core/utils/string.py
+++ b/src/cpl_core/utils/string.py
@@ -37,9 +37,19 @@ class String:
             String converted to snake_case
         """
         # convert to train-case to CamelCase
+        if "_" in chars:
+            chars = chars.replace("_", "-")
+
         if "-" in chars:
             chars = "".join(word.title() for word in chars.split("-"))
 
+        if " " in chars:
+            new_chars = ""
+            for word in chars.split(" "):
+                new_chars += String.first_to_upper(word)
+
+            chars = new_chars
+
         pattern1 = re.compile(r"(.)([A-Z][a-z]+)")
         pattern2 = re.compile(r"([a-z0-9])([A-Z])")
         file_name = re.sub(pattern1, r"\1_\2", chars)
diff --git a/unittests/unittests_core/test_startup_extension.py b/unittests/unittests_core/test_startup_extension.py
deleted file mode 100644
index 7c1939f3..00000000
--- a/unittests/unittests_core/test_startup_extension.py
+++ /dev/null
@@ -1,16 +0,0 @@
-from cpl_core.application.startup_extension_abc import StartupExtensionABC
-from cpl_core.configuration.configuration_abc import ConfigurationABC
-from cpl_core.dependency_injection.service_collection_abc import ServiceCollectionABC
-from cpl_core.environment.application_environment_abc import ApplicationEnvironmentABC
-
-
-class TestStartup_extension(StartupExtensionABC):
-
-    def __init__(self):
-        pass
-
-    def configure_configuration(self, config: ConfigurationABC, env: ApplicationEnvironmentABC):
-        pass
-
-    def configure_services(self, services: ServiceCollectionABC, env: ApplicationEnvironmentABC):
-        pass
diff --git a/unittests/unittests_core/utils/string_test_case.py b/unittests/unittests_core/utils/string_test_case.py
index 1fd4eddb..665117e4 100644
--- a/unittests/unittests_core/utils/string_test_case.py
+++ b/unittests/unittests_core/utils/string_test_case.py
@@ -1,10 +1,58 @@
+import string
 import unittest
 
+from cpl_core.utils import String
+
 
 class StringTestCase(unittest.TestCase):
 
     def setUp(self):
         pass
 
-    def test_equal(self):
-        pass
+    def test_convert_to_camel_case(self):
+        expected = "HelloWorld"
+
+        self.assertEqual(expected, String.convert_to_camel_case("hello-world"))
+        self.assertEqual(expected, String.convert_to_camel_case("hello_world"))
+        self.assertEqual("helloWorld", String.convert_to_camel_case("helloWorld"))
+        self.assertEqual(expected, String.convert_to_camel_case("Hello_world"))
+        self.assertEqual(expected, String.convert_to_camel_case("Hello_World"))
+        self.assertEqual(expected, String.convert_to_camel_case("hello world"))
+
+    def test_convert_to_snake_case(self):
+        expected = "hello_world"
+
+        self.assertEqual(expected, String.convert_to_snake_case("Hello World"))
+        self.assertEqual(expected, String.convert_to_snake_case("hello-world"))
+        self.assertEqual(expected, String.convert_to_snake_case("hello_world"))
+        self.assertEqual(expected, String.convert_to_snake_case("helloWorld"))
+        self.assertEqual(expected, String.convert_to_snake_case("Hello_world"))
+        self.assertEqual(expected, String.convert_to_snake_case("Hello_World"))
+        self.assertEqual(expected, String.convert_to_snake_case("hello world"))
+
+    def test_first_to_upper(self):
+        expected = "HelloWorld"
+
+        self.assertEqual(expected, String.first_to_upper("helloWorld"))
+        self.assertEqual(expected, String.first_to_upper("HelloWorld"))
+
+    def test_first_to_lower(self):
+        expected = "helloWorld"
+
+        self.assertEqual(expected, String.first_to_lower("helloWorld"))
+        self.assertEqual(expected, String.first_to_lower("HelloWorld"))
+
+    def test_random_string(self):
+        expected = ""
+
+        for x in range(0, 100):
+            rstr = String.random_string(string.ascii_letters, 4)
+            self.assertNotEqual(expected, rstr)
+            self.assertEqual(4, len(rstr))
+            expected = rstr
+
+        for x in range(0, 100):
+            rstr = String.random_string(string.ascii_letters, 16)
+            self.assertNotEqual(expected, rstr)
+            self.assertEqual(16, len(rstr))
+            expected = rstr