Reports methods marked with @DataProvider annotation that doesn't return Object[][] or Iterator<Object>. If another type is returned, TestNG throws an exception.

Example:


public class TestNgTest {
  @DataProvider(name = "Languages")
  List<String> getData() {
    return List.of("Java", "Kotlin");
  }

  @Test(dataProvider = "Languages")
  public void testData(String language) {
    System.out.println(language);
  }
}