public function testGroup()
{
$collection = new Collection([['date' => '2000-01-01', 'title' => 'First'], ['date' => '2000-01-01', 'title' => 'Second'], ['date' => '2000-01-02', 'title' => 'Third'], ['date' => '2000-01-04', 'title' => 'Fourth']]);
$grouped = $collection->group('date');
$this->assertEquals(['2000-01-01' => new Collection([['date' => '2000-01-01', 'title' => 'First'], ['date' => '2000-01-01', 'title' => 'Second']]), '2000-01-02' => new Collection([['date' => '2000-01-02', 'title' => 'Third']]), '2000-01-04' => new Collection([['date' => '2000-01-04', 'title' => 'Fourth']])], $grouped);
$grouped = $collection->group(function ($x) {
return date('m-d', strtotime($x['date']));
});
$this->assertEquals(['01-01' => new Collection([['date' => '2000-01-01', 'title' => 'First'], ['date' => '2000-01-01', 'title' => 'Second']]), '01-02' => new Collection([['date' => '2000-01-02', 'title' => 'Third']]), '01-04' => new Collection([['date' => '2000-01-04', 'title' => 'Fourth']])], $grouped);
}
