added unit test for counter

src/tests/Counter.test.js

@@ -1,22 +1,34 @@
-// import necessary react testing library helpers here
-// import the Counter component here
+import { render, screen, fireEvent } from '@testing-library/react'; 
+import Counter from '../components/Counter'; 
 
 beforeEach(() => {
-  // Render the Counter component here
-})
+  render(<Counter />); 
+});
 
 test('renders counter message', () => {
-  // Complete the unit test below based on the objective in the line above
+  const counterMessage = screen.getByText(/Counter/i); 
+  expect(counterMessage).toBeInTheDocument();
 });
 
 test('should render initial count with value of 0', () => {
-  // Complete the unit test below based on the objective in the line above
+  const initialCountDisplay = screen.getByText(/0/);
+  expect(initialCountDisplay).toBeInTheDocument(); 
 });
 
 test('clicking + increments the count', () => {
-  // Complete the unit test below based on the objective in the line above
+  const incrementButton = screen.getByRole('button', { name: '+' }); 
+  fireEvent.click(incrementButton); 
+  fireEvent.click(incrementButton); 
+  const countDisplay = screen.getByText(/2/); 
+  expect(countDisplay).toBeInTheDocument(); 
 });
 
 test('clicking - decrements the count', () => {
-  // Complete the unit test below based on the objective in the line above
+  const incrementButton = screen.getByRole('button', { name: '+' }); 
+  fireEvent.click(incrementButton); 
+  fireEvent.click(incrementButton); 
+  const decrementButton = screen.getByRole('button', { name: '-' }); 
+  fireEvent.click(decrementButton); 
+  const countDisplay = screen.getByText(/1/);
+  expect(countDisplay).toBeInTheDocument();
 });