Forcing Unit Testing on Developers

Unless you are a position of authority, the best thing you can do is to convince them of the value of the test suite.

It's very difficult to get developers to see the light on this issue if they aren't seeing it done right.

Try to pair with another developer and show them the benefits and the clarity that comes from writing the tests FIRST. If you don't do this, they are likely to write all of their code, get it working, and then write tests. So, from their point of view, it will feel like simply an extra task that doesn't help them get things done.

Also keep in mind that people often do not understand how to write good tests. Even more, some do not know how to make use of tools like jmock, which can lead to them getting stuck and giving up on writing a test.

Forcing anything onto anybody is not a good practise in my view. I would show them the benefits of TDD at every opportunity I get. This should automatically get the rest of the team to voluntarily practise TDD.

You don't want lip-service unit testing, you want whole-hearted unit testing. That isn't something that can be forced. What you need to do is influence your teammates over time to see the benefits of unit testing and to develop a unit testing culture.

To start with you need to understand that different people change for different reasons. In Crossing the Chasm terms, visionaries will adopt new techniques because they are better, but pragmatists adopt new techniques either because they solve a problem/pain the currently have or because everyone else is adopting it.

Your mission then it to show how unit testing can solve a pain your team currently feels. As you win over people one-by-one eventually you can reach a tipping point where unit testing is the norm and everyone goes along with it. However if you can't tie unit testing to a pain your team feels then your efforts to convince them will likely fail.