Can I add a junit test case at runtime?

java, junit

Solution

You can use @Parameterized. This will give you what you want. Here is a simple case, to run a test for all files in a single directory:

@RunWith(Parameterized.class)
public class ParameterizedTest {
    @Parameters(name = "{index}: file {0}")
    public static Iterable<Object[]> data() {
        File[] files = new File("/temp").listFiles();

        List<Object[]> objects = new ArrayList<Object[]>(files.length);

        for (File file : files) {
            objects.add(new Object[] { file.getAbsolutePath() });
        }

        return objects;
    }

    private final String filename;

    public ParameterizedTest(String filename) {
        this.filename = filename;
    }

    @Test
    public void test() {
        System.out.println("test filename=" + filename);
    }
}

Each test in the file is run once for each entry in the list returned by `data()`. You can obviously do what you want with the files, but if you're constructing the list of tests dynamically, then you'll need to have some way of constructing the pass/fail criteria also. So, if you're transforming lots of xml into other xml, then you'll need the resulting xml available as well, maybe in a different directory or with a different (but predictable) name.

Problem

Original source