Run results for: Test please

Run details:

User agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:50.0) Gecko/20100101 Firefox/50.0

Browser: Firefox 50

Operating system: Windows 7

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
Ifs	4951303.0 Ops/sec
Better	4010508.0 Ops/sec

Script Preparation code:

function getNameIF(firstName, lastName) {
  //cyclomatic complexity always starts from 1
  if (firstName && lastName) { //if operator, +1
    return firstName + ' ' + lastName;
  } else if (firstName) { // +1
    return firstName;
  } else if (lastName) { // +1
    return lastName;
  } else if (!firstName && !lastName) { // +1
    return 'stranger';
  }
}

function getNameOrFallback(name, fallback) {
  //complexity starts from 1
  return name || fallback; //|| operator, +1
  //total complexity is 2
}

function getNameBetter(firstName, lastName) {
  //complexity starts from 1
  let name = '';
  if (firstName) { //if operator, +1
    name = firstName;
  }
  if (lastName) { // +1
    name += ' ' + lastName;
  }
  //even though complexity for getNameOrFallback is 2, it doesn't add up to complexity of current function
  return getNameOrFallback(name.trim(), 'stranger');
  //total complexity is 3
}

var names = [
 {firstname:'Alan', lastname:'Tondelier'},
 {firstname:'Tedj', lastname:'Ferahti'},
 {firstname:'Dudu', lastname: null},
 {firstname: null, lastname: null},
];

Tests:

Ifs
names.forEach(function(item,i) { getNameIF(item.firstname, item.lastname); });
Better
names.forEach(function(item,i) { getNameBetter(item.firstname, item.lastname); });

Run results for: Test please

test

Ifs

Better