fetchData - Fetches data from an API endpoint

JavaScript code snippet:

/**
 * Fetches data from the specified API endpoint
 * @param {string} url - The URL of the API endpoint
 * @returns {Promise} - A Promise that resolves to the fetched data
 */
function fetchData(url) {
  return fetch(url)
    .then(response => response.json())
    .catch(error => {
      console.error('Error fetching data:', error);
      throw new Error('Failed to fetch data');
    });
}

/**
 * Unit test for fetchData function
 */
function testFetchData() {
  // Mock API endpoint
  const url = 'https://api.example.com/data';
  
  // Call fetchData function
  fetchData(url)
    .then(data => {
      // Assert that data is fetched successfully
      console.log('Data fetched successfully:', data);
    })
    .catch(error => {
      // Handle any errors
      console.error('Failed to fetch data:', error);
    });
}

Example usage:

// Call the fetchData function with the API endpoint URL
fetchData('https://api.example.com/data')
  .then(data => {
    // Process the fetched data
    console.log('Data:', data);
  })
  .catch(error => {
    // Handle any errors
    console.error('Error:', error);
  });

Unit testing:

To test the fetchData function, call the testFetchData function. The function mocks an API endpoint and verifies that the data is fetched successfully.

testFetchData();

Note: Make sure to replace the URL with the appropriate API endpoint for your specific use case.