Easy way to allow all transitions

[gjm]

If I have a model that has, let's say 10 states, but with no constraints in transitions. There should be an easy way to allow all transitions without the need to manually specify each one of them.

Something like (in config()):

return parent::config()->allowAllTransitions();

[JasperTey]

In toying with this, the best I was able to achieve with the current API is as follows.

abstract class ClientStatusState extends State
{
    public static function config(): StateConfig
    {
        // Manually specify the linear array of all N states
        $all = [
            InProgress::class,
            Complete::class,
            FallOff::class,
            ReferralOut::class,
        ];

        return parent::config()
            ->default(InProgress::class)
            ->allowTransitions(
                // ...but at least the (N*N) combinations can be taken care of for you.
                collect($all)->crossJoin($all)->toArray()
            );
    }
}

Where $all is the manually-specified array of all concrete states. And then from there, the crossJoin collection method alleviates the pain of assembling all possible pairs manually.

---

Of course, when there are changes in states (added, removed, etc), the $all array would have to be updated accordingly. A feature test can help "enforce that":

class ClientStatusStateTest extends TestCase
{
    /**
     * @dataProvider transitionProvider
     */
    public function testClientStatusCanTransition($from, $to)
    {
        $clientStatus = ClientStatus::factory()->create([
            'status' => $from
        ]);

        $this->assertTrue($clientStatus->status->canTransitionTo($to));
    }

    public function transitionProvider()
    {
        $states = ClientStatus::getStatesFor('status');

        return $states->crossJoin($states)
            ->mapWithKeys(function ($combo) {
                [$from, $to] = $combo;

                return [
                    "$from -> $to" => [$from, $to]
                ];
            });
    }
}

   PASS  Tests\Feature\ClientStatus\ClientStatusStateTest
  ✓ client status can transition with data set "Complete -> Complete"
  ✓ client status can transition with data set "Complete -> Fall Off"
  ✓ client status can transition with data set "Complete -> In Progress"
  ✓ client status can transition with data set "Complete -> Referral Out"
  ✓ client status can transition with data set "Fall Off -> Complete"
  ✓ client status can transition with data set "Fall Off -> Fall Off"
  ✓ client status can transition with data set "Fall Off -> In Progress"
  ✓ client status can transition with data set "Fall Off -> Referral Out"
  ✓ client status can transition with data set "In Progress -> Complete"
  ✓ client status can transition with data set "In Progress -> Fall Off"
  ✓ client status can transition with data set "In Progress -> In Progress"
  ✓ client status can transition with data set "In Progress -> Referral Out"
  ✓ client status can transition with data set "Referral Out -> Complete"
  ✓ client status can transition with data set "Referral Out -> Fall Off"
  ✓ client status can transition with data set "Referral Out -> In Progress"
  ✓ client status can transition with data set "Referral Out -> Referral Out"

[lloricode]

@JasperTey

how about if some of them has custom $transition?

[lloricode]

$all = [
    'A',
    'B',
];

$transitions = collect([
    [
        'A',
        'B',
        'xxx',
    ]
]);

collect($all)
    ->crossJoin($all)
    ->map(function ($value) use ($transitions) {
        if (
            $t = $transitions->where(0, $value[0])
            ->where(1, $value[1])
            ->first()
        ) {
            $value[] = $t[2];
        }

        return $value;
    })
    ->toArray();

=> [
     [
       "A",
       "A",
     ],
     [
       "A",
       "B",
       "xxx",
     ],
     [
       "B",
       "A",
     ],
     [
       "B",
       "B",
     ],
   ]```

[fmeccanici]

I recently implemented this feature in #238.

[zarulizham]

Hi, how to set registeredStates? I cannot set through $this->registeredStates = [...classes] because of public static function config()