Add a few basic util tests

src/tests/utils.test.ts

@@ -0,0 +1,24 @@
+import { wrapAround, containsOnlyLettersAndUnderscores, replaceIllegalFileNameCharactersInString} from '../utils/Utils';
+
+test('If wrapAround wraps correctly', () => {
+    expect(wrapAround(100,5)).toBe(0);
+    expect(wrapAround(100,7)).toBe(2);
+});
+
+test('If wrapAround errors out when dividing by zero', () => {
+    expect(wrapAround(100,0)).toThrow();
+});
+
+test('Letter and underscore string validity', () => {
+    expect(containsOnlyLettersAndUnderscores("asdkfj_")).toBe(true);
+    expect(containsOnlyLettersAndUnderscores("asdkfj0")).toBe(false);
+});
+
+test('Letter and underscore unicode char test', () =>{ 
+    expect(containsOnlyLettersAndUnderscores("asdkaÈj")).toBe(true);
+    expect(containsOnlyLettersAndUnderscores("asdkaÈj0")).toBe(false);
+});
+
+test('Valid filename test', ()=>{
+    expect(replaceIllegalFileNameCharactersInString("what?is\\this:")).toBe("whatisthis -");
+})