SanityTest.php

<?php

use PHPUnit\Framework\TestCase;

class HarnessTest extends TestCase {

    public function test_harness_is_in_place() {
        $this->assertTrue(TRUE);
    }

    public function test_side_effect_isolation_1_of_2() {
        $GLOBALS['foo'] = 1234;
    }

    /*
     * @depends test_side_effiect_isolation_1_of_2
     */
    public function test_side_effect_isolation_2_of_2() {
        $this->assertArrayNotHasKey('foo', $GLOBALS);
    }
}

?>