Idea/Improvement: Return Null When Requesting Relationship Data from Non Loaded Entities

[homestar9]

Related to this post on the Ortus community forums.

It would be great if, when requesting relationship data from a non-loaded (new) entity, Quick would return null (or an empty array where appropriate) just like if you performed the same operation from a loaded entity. This behavior should be more intuitive and also better follows the null object pattern.

Here's a simple example of how one might use this new change in Quick:

// Post.cfc
component 
    extends="quick.models.BaseEntity" 
    accessors="true" 
{

    // Post belongs to an Author
    function author() {
        return belongsTo( "User" );
    }

}

// Posts.cfc Handler
function index( event, rc, prc ) {
	
	// Get an existing entity, or return a new one if not found
	prc.post = getInstance( "Post" )
		.firstOrCreate( rc.id );

	// return the memento with the author (it will either be null or populated)
	return prc.post.getMemento( "author" );

}

[bdw429s]

This issue has been mentioned on Ortus Solutions Community. There might be relevant details there:

https://community.ortussolutions.com/t/quick-4-2-4-this-instance-is-not-loaded-so-it-cannot-access-the-relationship/9216/1

[homestar9]

One way to enable this behavior would be to make the following code changes:

BaseEntity.cfc

1. Remove calls to guardAgainstNotLoaded() in relationship calls like in belongsTo()
2. Add the following to isNullValue()

if ( !arguments.keyExists( "value" ) ) {
     return true;
}

I'm coming from a place of not being very familiar with Quick, but based on some "hack and slash" experiments, this change appears to work.

[homestar9]

@elpete Submitted a pull request for your review.
#178

Please be gentle, this is my first Quick PR. ;)