Use ParameterBag for PluginDefinition ?

"plugin definitions" ("the info array about a given plugin implementation") are mostly used property by property rather than for the array as a whole.

They are currently retrieved through methods or functions, so using a property has to be done in two steps :

$definition = $plugin_type->getPluginDefinition($plugin_id); // or $plugin->getPluginDefinition() with #1540206: Allow self inspection on instantiated plugin objects
$foo = $definition['bar'];

Having the discovery classes return the definition as a (Symfony) ParameterBag would make this much more fluent :

$foo = $plugin_type->getPluginDefinition($plugin_id)->get('bar');