Functional\Tests\UniqueTest::testPassingNullAsCallback PHP Метод

    public function testPassingNullAsCallback()
    {
        $this->assertSame([0 => 'value1', 1 => 'value2', 3 => 'value'], unique($this->list));
        $this->assertSame([0 => 'value1', 1 => 'value2', 3 => 'value'], unique($this->list, null));
        $this->assertSame([0 => 'value1', 1 => 'value2', 3 => 'value'], unique($this->list, null, false));
        $this->assertSame([0 => 'value1', 1 => 'value2', 3 => 'value'], unique($this->list, null, true));
    }