Unit Testing

Unit testing tests individual components. Each test runs in isolation, and tests only a single item, such as a function or method. If a unit test involves multiple interacting objects, then you have written an integration test.

For example, if I have this function:

function add( $a, $b ) {
  return $a + $b;
}

A unit test might check:

• If 5+5 = 10
• That 2+3 is not 7
• That 0+0 does not fail

Tools for Unit Testing

• PHPUnit
• PHPSpec

Helpful Projects and Further Reading

• John P Blochs WP Unit Test Starter project
• WP Mock
• Writing Unit Tests for WordPress