Optimize the non-cached clipboard to only fetch relevant abilities

[JosephSilber]

Current situation

Currently, the clipboard will always fetch all abilities when checking anything at the gate. The abilities are cached (by default for the current request, but can also be cached forever by calling the cache() method on Bouncer).

This is great if you only use a handful of abilities, since pulling them all down once and then running all checks against that set of abilities is very efficient.

However, if you use abilities for specific models, like:

Bouncer::allow($user)->to('view', $listing);

...you can quickly end up with users who have hundreds of abilities. Pulling down all abilities to run a single check becomes a performance penalty instead of an improvement.

Improvement in this PR

With this PR, the non-caching clipboard now only pulls down the single relevant ability for the given check. So if you configure Bouncer not to cache your queries:

Bouncer::dontCache();

...it now will no longer pull all abilities from the database at once.

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After merging this and having people try it out, I plan to create an additional caching clipboard based on this one, that only caches the results of the checks at the gate.

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References #263

[JosephSilber]

Since this is a pretty big change that required refactoring almost all tests, I would really appreciate if any of you could try this out in your apps to see if it actually works as expected.

How to try it

1. Update the Bouncer version in composer.json to master:

   "silber/bouncer": "dev-master"
   

2. Run composer update.

3. Configure Bouncer not to cache anything, by putting the following in your AppServiceProvider's boot method:

   \Bouncer::dontCache();

4. Run your tests and/or click around in your app to make sure everything works as expected.

Please report back with your findings ❤️