Skip test if its data provider provides no data

TestNG Version

TestNG version 7.4.0

Expected behavior

Some message should be display so end user can usderstand what is the problem

Actual behavior

I get the blank output

Is the issue reproducible on runner?

[X] TestNG

Test case sample

I try to execute the simple test case which call dataProvider and this dataProvider has return type as Iterator<Object[]>,i know this return type is not accept by @DataProvider method but after execute the below program i get the blank output nothing is display in console,i accept at least message like the dataProvider is not exist, please refer below program.

public class Practice {


  @Test(dataProvider = "NotWorking")
  public void testCase(Object[] obj) {
    System.out.println(obj[0]);
    System.out.println(obj[1]);
  }

  @DataProvider(name = "NotWorking")
  public Iterator<Object[]> dataProvider2() {
    List<Object[]> obj = new ArrayList<Object[]>();
    Object[] obj1 = new Object[2];
    obj1[0] = new String("First_Object_First_value");
    obj1[1] = new String("First_Object_Second_value");
    Object[] obj2 = new Object[2];
    obj2[0] = new String("Second_Object_First_value");
    obj1[1] = new String("Second_Object_Second_value");
    Iterator<Object[]> itr = obj.iterator();
    return itr;
  }
}

i get the below output for above code,

[RemoteTestNG] detected TestNG version 7.4.0
===============================================
Default test
Tests run: 1, Failures: 0, Skips: 0

[juherr]

But testng at least provide message like this test method does not get any data so it was not execute

That’s an excellent idea!

[krmahadevan]

@juherr

a data provider either returns an Iterator on an empty collection or

We have a proper warning message for this, but its the logger that is goofing up things for us. Our customised logger by default sets the log levels for every logger instance to WARN (3). And we are logging the problem at an INFO level.

https://github.com/cbeust/testng/blob/54329910b9b729b836620aafe926e58cbc4a7dc7/testng-core/src/main/java/org/testng/internal/Parameters.java#L803-L809

So we should be doing a few things here.

1. Consider implementing https://github.com/cbeust/testng/issues/2646 so that a user can basically work with configuring the logger in a much more easier way. TestNG logging has the following problems:
   1. Its custom written
   2. Its confined to ONLY console logging
   3. Lacks documentation (I think we can fix this)
2. As a temporary fix for this problem, maybe change the logging level from INFO to WARN for the above code in question.

I am going to raise a PR which implements (2) and a separate PR which addresses (1)