在netbeans上运行测试后,phpunit展示了测试通过。 (0.0s)虽然不应该

Information on the tools:
Netbeans 8.2
XAMPP V3.2.2
PHPUnit 3.7.21 by Sebastian Bergmann.
phpunit-skelgen 2.0.1 by Sebastian Bergmann.

HelloWorld:

<?php

namespace HelloWorld;

class HelloWorld
{
    /**
     * @assert (0, 0) == 0
     * @assert (0, 1) == 1
     * @assert (1, 0) == 1
     * @assert (1, 1) == 2
     * @assert (1, 2) == 4
     */
    public function add($a, $b)
    {
        return $a + $b;
    }
}

HelloWorldTest:

<?php

namespace HelloWorld;

/**
 * Generated by PHPUnit_SkeletonGenerator on 2019-05-05 at 11:24:04.
 */
class HelloWorldTest extends \PHPUnit_Framework_TestCase {

    /**
     * @var HelloWorld
     */
    protected $object;

    /**
     * Sets up the fixture, for example, opens a network connection.
     * This method is called before a test is executed.
     */
    protected function setUp() {
        $this->object = new HelloWorld;
    }

    /**
     * Tears down the fixture, for example, closes a network connection.
     * This method is called after a test is executed.
     */
    protected function tearDown() {

    }

    /**
     * Generated from @assert (0, 0) == 0.
     *
     * @covers HelloWorld\HelloWorld::add
     */
    public function testAdd() {
        $this->assertEquals(
                0, $this->object->add(0, 0)
        );
    }

    /**
     * Generated from @assert (0, 1) == 1.
     *
     * @covers HelloWorld\HelloWorld::add
     */
    public function testAdd2() {
        $this->assertEquals(
                1, $this->object->add(0, 1)
        );
    }

    /**
     * Generated from @assert (1, 0) == 1.
     *
     * @covers HelloWorld\HelloWorld::add
     */
    public function testAdd3() {
        $this->assertEquals(
                1, $this->object->add(1, 0)
        );
    }

    /**
     * Generated from @assert (1, 1) == 2.
     *
     * @covers HelloWorld\HelloWorld::add
     */
    public function testAdd4() {
        $this->assertEquals(
                2, $this->object->add(1, 1)
        );
    }

    /**
     * Generated from @assert (1, 2) == 4.
     *
     * @covers HelloWorld\HelloWorld::add
     */
    public function testAdd5() {
        $this->assertEquals(
                4, $this->object->add(1, 2)
        );
    }
}

After run Test on netbeans, phpunit exhibits

the test passed. (0.0s)

while it should not

It seems there is a bug

Tools/Options=> PHPUnit Script is selected and

PHPUnit 3.7.21 by Sebastian Bergmann.

is returned from Command prompt when version is requested

Tools/Options=> Skeleton Generator Script is selected and

phpunit-skelgen 2.0.1 by Sebastian Bergmann.

is returned from Command prompt when version is requested