add: util tests

packages/core/tests/utils/utils.test.ts

@@ -0,0 +1,34 @@
+import { getRandomElement } from '../../src/lib/utils';
+
+describe('getRandomElement', () => {
+  it('should return a valid element (Small Array ~ 1k elements)', () => {
+    const testArray = Array.from(
+      { length: 1000 },
+      (_, i) => `https://validator/${i}`
+    );
+    const element = getRandomElement(testArray);
+    expect(testArray).toContain(element);
+  });
+
+  it('should return a valid element (Large Array ~ 10k elements)', () => {
+    const testArray = Array.from(
+      { length: 10000 },
+      (_, i) => `https://validator/${i}`
+    );
+    const element = getRandomElement(testArray);
+    expect(testArray).toContain(element);
+  });
+
+  it('should return a valid element (Large Array ~ 100k elements)', () => {
+    const testArray = Array.from(
+      { length: 100000 },
+      (_, i) => `https://validator/${i}`
+    );
+    const element = getRandomElement(testArray);
+    expect(testArray).toContain(element);
+  });
+
+  it('should throw an error if array length is 0', () => {
+    expect(() => getRandomElement([])).toThrow('Array cannot be empty');
+  });
+});