There are times when I really love what I do for a living. Today is one of them.

I'm working with software developers in one of the world's most well-known media organisations, and we have just had a visit and a talk from a very well known software development writer and "thought leader".

The buzz among those who attended this guy's talk is palpable today. It feels like we've shifted up a gear. A requirements analyst sitting next to me says he's planning to start writing code again. That NEVER happens!

"compared to Java code, XML is agile and flexible. Compared to Python code, XML is a boat anchor, a ball and chain."
    - Phillip J. Eby

If you are new to Python and coming from Java (or C#, or other similar statically typed OO language), these classic articles from PJE and Ryan Tomayko are necessary reading:

Recently, somewhere in the Caribbean Sea, you implemented the PirateShip class. You want to test the cannons thoroughly in preparation for a clash with the East India Company. This requires that you run the crucial testFireCannonDepletesAmmunition() method many times with many different inputs.

TestNG is a test framework for Java unit tests that offers additional power and ease of use over JUnit. Some of TestNG's features will help you to write your PirateShip tests in such a way that you'll be well prepared to take on the Admiral. First is the @DataProvider annotation, which allows you to add parameters to a test method and provide argument values to it from a data provider.

public class PirateShipTest {
  @Test(dataProvider = "cannons")
  public void testFireCannonDepletesAmmunition(int ballsToLoad,
         int ballsToFire,
         int expectedRemaining) {
    PirateShip ship = new PirateShip("The Black Pearl");
    ship.loadCannons(ballsToLoad);
    for (int i = 0; i < ballsToFire; i++) {
      ship.fireCannon();
    }
    assertEquals(ship.getBallsRemaining(), expectedRemaining);
  }
  @DataProvider(name = "cannons")
  public Object[][] getShipSidesAndAmmunition() {
    // Each 1-D array represents a single execution of a @Test that
    // refers to this provider. The elements in the array represent
    // parameters to the test call.
    return new Object[] {
      {5, 1, 4}, {5, 5, 0}, {5, 0, 5}
    };
  }
}