public function testStartsWith()
{
$str = new Str("Hello, world.");
$this->assertTrue($str->startsWith("H"));
$this->assertTrue($str->startsWith("Hello,"));
$this->assertTrue($str->startsWith("HE", 0, true));
$this->assertTrue($str->startsWith("HE", null, true));
$this->assertFalse($str->startsWith("."));
$this->assertFalse($str->startsWith("world."));
$this->assertFalse($str->startsWith("LD."));
}
