public function testToLink()
{
$this->assertEquals('abc-def-gh-12', Str::toLink('Ąbć-DEF? Gh: 12'));
$this->assertEquals('abc_def_gh_12', Str::toLink('Ąbć-DEF? Gh: 12', '_'));
$this->assertEquals('abcdefgh', Str::toLink('Ąbć-DEF? Gh: 12', '_', 'a-zA-Z'));
}