Refactoring Example

RefactoringExample1.js

function formatUsersBadWay(users) {
  // Keep only valid users: phone & email not null
  for (let i = 0; i < users.length; i++) {
    const user = users[i];
    if (user.email === null || user.phone === null) {
      users.splice(i, 1);
    }
  }

  // Sort by name alphabetically
  users.sort(function (a, b) {
    if (a.name < b.name) {
      return -1;
    }
    if (a.name > b.name) {
      return 1;
    }
    return 0;
  });

  // Transform fields for UI display
  users.forEach(function (user) {
    if (
      user.address !== null &&
      user.address.zipcode !== null &&
      user.address.street !== null &&
      user.address.city !== null
    ) {
      user.address = `Living at: ${user.address.zipcode} ${user.address.street} ${user.address.city}`;
    }
    if (user.phone !== null) {
      user.phone = `Phone number: ${user.phone}`;
    }
    if (
      user.company !== null &&
      user.company.name !== null &&
      user.company.catchPhrase !== null &&
      user.company.bs !== null
    ) {
      user.company = `Company: ${user.company.name.toUpperCase()} - ${user.company.catchPhrase.toLowerCase()}, ${user.company.bs}`;
    }
  });

  return users;
}


// Extracted helper function for formatting a single user
function formatUserDetails(user) {
  return {
    ...user,
    address: formatAddress(user.address),
    phone: formatPhone(user.phone),
    company: formatCompany(user.company),
  };
}

// Helper function: Formats Address
function formatAddress(address) {
  return address
    ? `Living at: ${address.zipcode} ${address.street} ${address.city}`
    : "Address unavailable";
}

// Helper function: Formats Phone
function formatPhone(phone) {
  return phone ? `Phone number: ${phone}` : "Phone unavailable";
}

// Helper function: Formats Company Info
function formatCompany(company) {
  return company
    ? `Company: ${company.name.toUpperCase()} - ${company.catchPhrase.toLowerCase()}, ${company.bs}`
    : "Company details unavailable";
}

function formatUsers(users) {
  return users
    .filter(user => user.email !== null && user.phone !== null)
    .sort((a, b) => a.name.localeCompare(b.name))
    .map(formatUserDetails);
}