public function testAddScheme()
{
$this->assertEquals('http://example.org', Html::addScheme('example.org'));
$this->assertEquals('http://example.org', Html::addScheme('http://example.org'));
$this->assertEquals('https://example.org', Html::addScheme('https://example.org'));
$this->assertEquals('mailto:[email protected]', Html::addScheme('mailto:[email protected]'));
}