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Usage

The basic idea is that you write test methods inline with the code you want to test.

package hello;

// Functionality of the package
public void printHello(PrintWriter w)
{
  // Implementation
}

// Now, let's test it
void _test()
{
  let result = new StringWriter();

  printHello(new PrintStream(s);

  assert result.toString().equals("Hello");
}

void _testSomethingElse()
{ ... }

Now, compile your package: nicec -a hello.jar hello. And test it: niceunit --classpath hello.jar hello. It will run every method in the package whose name starts with _test, and report errors for any that raises an assertion error or other exceptions.

(We could very simply add the functionality in nicec to start the unit tests if the compilation succeded. Should this by default be turned on or off?)

There is also an Ant task to start niceunit, and the Maven plugin automatically starts testing as needed.

Design questions

One important design specificity is that test code is close to the code it tests, typically in the same file. You could of course put it in a different file (then you won't have access to private features) or in a different package (e.g. hello.test), where you can test only public features of =hello. These three possibilities actually allow you to do, respectively, white box testing (testing the implementation, including private memebers), black box testing of the interface visible to the package, and public black box testing.

Is this good? Is this heretic? (If it's heretic, is that bad or good? :-)

JUnit

It is also possible to make use of the JUnit framework. At the moment it is not very convenient to do so, but that could be helped.

A question is: is it important to make use of JUnit? There are actually two issues:

• is it important that there is also a way to write "JUnit-style" test classes?
• should the above testing framwork be based on JUnit? what would that bring?

-- DanielBonniot - 18 Feb 2004

• is it important that there is also a way to write "JUnit-style" test classes?

• should the above testing framework be based on JUnit? what would that bring?