Is there a way to know inside a @MethodSource for which test method it's providing data?

Question

In my TestClass I have a lot of different test methods that all have to run with the same data and therefore have the same @MethodSource :

 public class TestClass {
    private class TestData { /* some fields */ }
    private List<TestData> testDataTemplates = asList( 
        new TestData(...),
        /* some more elements */ 
    );

    static private Stream<Arguments> testDataProvider {
        List<TestData> testData = new ArrayList<>();
        // Here we do some nested .forEach iterating over the testDataTemplates
        return testData.stream();
    }

    @ParametrizedTest
    @MethodSource("testDataProvider")
    public void testMethod1(...) { }

    // some more test methods

    @ParametrizedTest
    @MethodSource("testDataProvider")
    public void testMethodN(...) { }

}

For testMethodN it is necessary to have the data a tiny bit different than for the other methods. My idea was to detect inside testDataProvider for which method it is currently generating data and adapt the output accordingly.

Is there a way to do so?
If not, what it the cleanest way to achieve what I need to, underlining again, that the output of testDataProvider for testMethodN is really really similar to the output for the other test methods?

Answer 1

One could solve this using a new @MethodSource :

static private Stream<Arguments> filteredTestDataProvider() {
    List<Arguments> testCases = new ArrayList<>();

     testDataProvider().forEach(args -> {
          // decide whether and how the current args are used
     });

     return testCases.stream();
}

And, of course, the @MethodSource("filteredTestDataProvider") of testMethodN should be adapted accordingly.