TDD …how?

Question

I\'m about to start out my first TDD (test-driven development) program, and I (naturally) have a TDD mental block..so I was wondering if someone could help guide me on where

Answer 1

First, start thinking "the testS", plural, rather than "the test", singular. You should expect to write more than one.

Second, if you have mental block, consider starting with a simpler challenge. Lower the difficulty until it's real easy to do, then move on to more substantial work.

For instance, assume you already have a byte array with the binary data, so you don't even need to think about sockets. All you need to write is something that takes in a byte[] and return an instance of your object. Can you write a test for that ?

If you still have mental block, lower it yet another notch. Assume your byte array is only going to contain default values anyway. So you don't even have to worry about the parsing, just about being able to return an instance of your object that has all values set to the defaults. Can you write a test for that ?

I imagine something like:

public void testFooReaderCanParseDefaultFoo() {
  FooReader fr = new FooReader();
  Foo myFoo = fr.buildFoo();
  assertEquals(0, myFoo.bar());
}

That's rock bottom, right ? You're only testing the Foo constructor. But you can then move up to the next level:

public void testFooReaderGivenBytesBuildsFoo() {
  FooReader fr = new FooReader();
  byte[] fooData = {1};
  fr.consumeBytes(fooData);
  Foo myFoo = fr.buildFoo();
  assertEquals(1, myFoo.bar());
}

And so on...