@Test
    public void shouldGetZeroCountWhenNoNullsPresent() {
        var nullsCountFunc = new FunctionCountNulls();
        values.forEach(value -> nullsCountFunc.accumulate(value, false));
        MatcherAssert.assertThat(nullsCountFunc.getResult(0), CoreMatchers.is(expectedCount));
    }
Test data

@return parameters for test
test/org.jkiss.dbeaver.test.platform/src/org/jkiss/dbeaver/model/data/aggregate/FunctionCountNullsTest.java