Adds new convenience methods

[kellymears]

In my Bedrock projects I typically extend the Config class with some simple static methods which I have found to have broad utility. It is the aim of this PR to have them integrated into the core Config class.

I think that they are a good fit for inclusion here as they promote readability while also not over-complicating or obscuring implementation details (a central tenant of the Bedrock project.)

Further I am happy to submit a PR to the Bedrock repo taking advantage of the features included here, should there be interest. Or, it could just be left to be adopted incrementally.

Note that I have not updated the test suite. Personally I think adding @covers annotations to the existing methods would be sufficient, since the new methods are simply wrapping existing methods.

Examples of the syntax this PR enables

/**
 * Configure auth keys and salts.
 */
Config::defineSet([
    'AUTH_KEY' => env('AUTH_KEY'),
    'AUTH_SALT' => env('AUTH_SALT'),
    'LOGGED_IN_KEY' => env('LOGGED_IN_KEY'),
    'LOGGED_IN_SALT' => env('LOGGED_IN_SALT'),
    'NONCE_KEY' => env('NONCE_KEY'),
    'NONCE_SALT' => env('NONCE_SALT'),
    'SECURE_AUTH_KEY' => env('SECURE_AUTH_KEY'),
    'SECURE_AUTH_SALT' => env('SECURE_AUTH_SALT'),
]);

if (Config::containsKey('DISPLAY_ERRORS')) {
    ini_set('display_errors', Config::get('DISPLAY_ERRORS'));
}

if (Config::containsKeys(['SENTRY_DSN', 'WP_ENV']) &&
    ! Config::is('WP_ENV', 'development')) {
    \Sentry\init([
        'dsn'         => Config::get('SENTRY_DSN'),
        'environment' => Config::get('WP_ENV'),
        'release'     => Config::get('GIT_SHA'),
        'error_types' => E_ALL & ~E_NOTICE & ~E_DEPRECATED,
    ]);
}

[coveralls]

Pull Request Test Coverage Report for Build 64

• 0 of 7 (0.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-29.2%) to 70.833%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/Config.php	0	7	0.0%

Totals
Change from base Build 61:	-29.2%
Covered Lines:	17
Relevant Lines:	24

---

💛 - Coveralls

[austinpray]

Nice!! Yeah these are definitely good updates. I added some suggestions to make the API's behavior a bit clearer in my eyes.

Add some tests 👍

[austinpray]

Now that we php 7.1+ now: wanna add a buncha type hints and stuff?

[strarsis]

This what I am using for the Redis plugin:

// Redis cache server config (WP Redis plugin)
if (env('REDIS_HOST')) {
    $_SERVER['CACHE_HOST'] = env('REDIS_HOST');
}

$_SERVER['CACHE_PORT'] = env('REDIS_PORT'); // WP Redis plugin expects a defined PORT

if (env('REDIS_PASSWORD')) {
    $_SERVER['CACHE_PASSWORD'] = env('REDIS_PASSWORD');
}
if (env('REDIS_SALT')) {
    Config::define('WP_CACHE_KEY_SALT', env('REDIS_SALT')); // salt uses a constant instead of `$_SERVER` !
}
if (env('REDIS_DB_NO')) {
    $_SERVER['CACHE_DB'] = env('REDIS_DB_NO');
}

Interestingly, WP_CACHE_KEY_SALT is expected to be a constant instead a $_SERVER variable key.
Does the convenience mechanism described above also handle those constants?