diff --git a/test/longestItem.test.js b/test/longestItem.test.js
index b0a6fc999..03feb27ce 100644
--- a/test/longestItem.test.js
+++ b/test/longestItem.test.js
@@ -19,8 +19,10 @@ test('Returns the longest array', () => {
 test('Returns the longest object when comparing arrays and strings', () => {
   expect(longestItem([1, 2, 3], 'foobar')).toEqual('foobar');
 });
-test('Returns undefined without any input', () => {
-  expect(longestItem()).toEqual(undefined);
+test('Returns TypeError without any input', () => {
+  expect(() => {
+    longestItem();
+  }).toThrow(TypeError);
 });
 test('Returns first found of all similar', () => {
   expect(longestItem('a', 'b', 'c')).toEqual('a');
diff --git a/test/toTitleCase.test.js b/test/toTitleCase.test.js
new file mode 100644
index 000000000..cc46ad6d8
--- /dev/null
+++ b/test/toTitleCase.test.js
@@ -0,0 +1,48 @@
+const expect = require('expect');
+const {toTitleCase} = require('./_30s.js');
+
+test('toTitleCase is a Function', () => {
+  expect(toTitleCase).toBeInstanceOf(Function);
+});
+test("toTitleCase('some_database_field_name') returns Some Database Field Name", () => {
+  expect(toTitleCase('some_database_field_name')).toBe('Some Database Field Name');
+});
+test("toTitleCase('Some label that needs to be titled') returns Some Label That Needs To Be Titled", () => {
+  expect(toTitleCase('Some label that needs to be titled')).toBe(
+    'Some Label That Needs To Be Titled'
+  );
+});
+test("toTitleCase('some-javaScript-property') return Some Java Script Property", () => {
+  expect(toTitleCase('some-javaScript-property')).toBe('Some Java Script Property');
+});
+test("toTitleCase('some-mixed_string with spaces_underscores-and-hyphens') returns Some Mixed String With Spaces Underscores And Hyphens", () => {
+  expect(toTitleCase('some-mixed_string with spaces_underscores-and-hyphens')).toBe(
+    'Some Mixed String With Spaces Underscores And Hyphens'
+  );
+});
+test('toTitleCase() throws a error', () => {
+  expect(() => {
+    toTitleCase();
+  }).toThrow();
+});
+test('toTitleCase([]) throws a error', () => {
+  expect(() => {
+    toCamelCase([]);
+  }).toThrow();
+});
+test('toCamelCase({}) throws a error', () => {
+  expect(() => {
+    toTitleCase({});
+  }).toThrow();
+});
+test('toTitleCase(123) throws a error', () => {
+  expect(() => {
+    toTitleCase(123);
+  }).toThrow();
+});
+let start = new Date().getTime();
+toTitleCase('some-mixed_string with spaces_underscores-and-hyphens');
+let end = new Date().getTime();
+test('toTitleCase(some-mixed_string with spaces_underscores-and-hyphens) takes less than 2s to run', () => {
+  expect(end - start < 2000).toBeTruthy();
+});