I am developing a Laravel App and stumbled upon a problem with Carbon library, so I tested some things and found out that this code:
// Date Diff 1
$st1 = Carbon::parse("2022-11-01");
$fi1 = Carbon::parse("2023-04-01");
$diff1 = $st1->diffInMonths($fi1);
// Date Diff 2
$st2 = Carbon::parse("2022-11-01");
$fi2 = Carbon::parse("2023-03-01");
$diff2 = $st2->diffInMonths($fi2);
dd([
'Diff 1' => "2022-11-01 -> 2023-04-01 = $diff1",
'Diff 2' => "2022-11-01 -> 2023-03-01 = $diff2",
]);
returns this:
"Diff 1" => "2022-11-01 -> 2023-04-01 = 5"
"Diff 2" => "2022-11-01 -> 2023-03-01 = 3"
Can anyone possibly explain to me why it is working this way, or even a suggestion as to how I could fix it.
As to the versions, I am using Laravel 5.7 and PHP 7.2.5
If you try that, you can find a similar problem:
$d1 = new \DateTime('2023-02-01');
$d2 = new \DateTime('2023-03-01');
$diff = date_diff($d1,$d2);
dump($diff->m); // months: 0
dump($diff->d); // days: 28
die;
The problem comes from PHP and not from Laravel, and is linked to the month of "February" (because there are only 28 days in February).
A solution could be to use this:
// Date Diff 1
$st1 = Carbon::parse("2022-11-01");
$fi1 = Carbon::parse("2023-04-01");
$diff1 = (int)$st1->floatDiffInMonths($fi1);
// Date Diff 2
$st2 = Carbon::parse("2022-11-01");
$fi2 = Carbon::parse("2023-03-03");
$diff2 = (int)$st2->floatDiffInMonths($fi2);
dd([
'Diff 1' => "2022-11-01 -> 2023-04-01 = $diff1", // 5
'Diff 2' => "2022-11-01 -> 2023-03-01 = $diff2", // 4
]);