[FIX #14] Add config for IO/initialize in default function

[aretheregods]

Fixes #14
How about this?

[lukeed]

Looking good! Few comments, but let's await feedback before making changes 😄

[lukeed]

Let's remove this – as is, this just redefines the existing defaults without a way to customize it.

[lukeed]

Let's replace this with a config object that allows the user to directly manipulate the IO settings.

Suggested change

	}, observerConfig);
	}, options.config || {});

The only drawback here is that it requires the user to know what those options are... but we can easily link to its options in the docs IMO. Plus, I personally prefer to expose native options, rather than reinvent them with new names.

What do you think @addyosmani ?

[aretheregods]

Yeah, I was gonna do that. But I didn't wanna add something to options without advisement. I'll make that change.

[addyosmani]

I just wanted to add that I'm in support of exposing native names vs defining our own variants where possible 👍

Thanks for working on this, @aretheregods!

[aretheregods]

I removed observerConfig, but still need to add the exposed options for options.config.

[aretheregods]

I added the JSDoc params for each IO property with their standard names.

 @param {Object} options.config - IntersectionObserver configuration options
 @param {Element} options.config.root - The root container in which elements are observed
 @param {string} options.config.rootMargin - Margin added to root before intersection observation testing
 @param {number} options.config.threshold - percentage of observed element in root before IO callback is called

And I set config to an empty object in options and then just passed that to IO setup.

    el: document,
    config: {},
  }, options);

       if (toPrefetch.has(url)) prefetcher(url);
      }
    });
  }, options.config);

Please let me know if this works for you?

[addyosmani]

As a passing note, it looks like this will need to be rebased against master ♻️

[aretheregods]

@addyosmani I believe that rebasing business might possibly be resolved...

P.S. Have a great holiday, guys

[addyosmani]

@lukeed I believe this PR managed to address most of our feedback. Was there anything else remaining before you were happy to sign off on it?

@aretheregods sorry to ask again - would you mind rebasing one more time? It's entirely my fault for not circling back to wrap up reviews when you first tried addressing our feedback. Would love to wrap this one up.

[lukeed]

We don't need this line, as new IntersectionObserver(noop, undefined) is still valid 😆

Suggested change

config: {}

[addyosmani]

@aretheregods a friendly ping. Looks like we are close to this being landable :)