A little Laravel helper function for hijacking Carbon's "now()" inside a callback

time_travel_helper.php

<?php

// Helper usage:
// timeTravel(Carbon::parse('one year ago'), function () {...});

function timeTravel($target, $callback) {
    Illuminate\Support\Carbon::setTestNow($target);

    return tap($callback(), function () {
        Illuminate\Support\Carbon::setTestNow();
    });
}

// Macro usage:
// Carbon::parse('last year')->timeTravel(function() {...}};

Illuminate\Support\Carbon::macro('timeTravel', function ($callback) {
    $target = $this;

    Illuminate\Support\Carbon::setTestNow($target);

    return tap($callback(), function () {
        Illuminate\Support\Carbon::setTestNow();
    });
});