/**
* Tests that the map function will return an instance of None
* if the callable passed returns None
*/
public function testMapReturnsAbsentOnAbsent()
{
$present = $this->getPresent();
$mapped = $present->map(function ($string) {
return Optional::absent();
});
$this->assertInstanceOf('Bart\\Optional\\None', $mapped);
}
public function testFromNullable()
{
$value = 'box_rox';
$present = Optional::fromNullable($value);
$this->assertInstanceOf('Bart\\Optional\\Some', $present);
$this->assertEquals($value, $present->get());
$absent = Optional::fromNullable(null);
$this->assertInstanceOf('Bart\\Optional\\None', $absent);
}
/**
* Returns an Optional containing the result of calling $callable on
* the contained value. If no value exists, as in the case of None, then
* this method will simply return None. The method will return None
* if the result of applying $callable to the contained value is null.
* @param callable $callable
* @return Some|None
*/
public function map(callable $callable)
{
return Optional::absent();
}