Make dom nodes created from v accessible in a widget

[matt-gadd]

At the moment the only mechanism we have for accessing a dom node is via maquette's afterCreate and afterUpdate methods which are per v call which is a bit clunky. We perhaps should provide a a mechanism in WidgetBase that allows you to access all dom nodes in a widget by key, as well as a lifecycle function on WidgetBase where you know these will be available.

[edhager]

I did some prototyping and came up with one possible solution: edhager@2d24075

It uses the render decorator mechanism in WidgetBase.

[edhager]

I started updating WidgetBase with code based on what was done in the prototype. My progress is in https://github.com/edhager/widget-core/tree/widgetbase-node-lifecycle.

I have not written any tests yet. At this point, all I know is my code compiles.

[edhager]

I added some tests and fixed some bugs. Getting close. I am not sure how to write a test for the afterCreate calls.

[bitpshr]

Not sure how relevant my approach is for your work, but when testing widget afterCreate calls, I pass in an object cast to any instead of an event, and verify certain properties or functions are called on that object.

[edhager]

I just added some update tests and there is a problem with my code. The way I am adding the afterCreate and afterUpdate callbacks in a render decorator is giving me this error:

Error: Functions may not be updated on subsequent renders (property: afterCreate). Hint: declare event handler functions outside the render() function.

I may have to rethink my approach.

[edhager]

I fixed the problem with the way I was registering the afterCreate and afterUpdate callbacks. A vdom update now works. I think I have everything working now.

https://github.com/edhager/widget-core/tree/widgetbase-node-lifecycle

[edhager]

I think my code may still have an issue. I am storing existing afterCreate and afterUpdate callbacks in maps using properties.key as the key to the map. That is not good enough because I think keys can be reused in different child lists.

[edhager]

I fixed the duplicate key issue.