[BUG] Genesis widget always re-renders on first refresh cycle

[saqimtiaz]

A genesis widget with non-$-prefixed attributes will always re-render itself and its contents on the first refresh cycle. This is because in the render method, the widget only computes the attributes starting with $. As a result, the first time the widget's refresh method is run, computeAttributes() returns false positives for all attributes not starting with $ suggesting that they have changed. The refresh method should also ignore all attributes not prefixed with $.

To test:

1. create tiddler A with the text

<$genesis type="div">
<<now [UTC]YYYY0MM0DD0hh0mm0ssXXX>>

</$genesis>

2. Click the new tiddler button and watch the display of tiddler A update.

[pmario]

@saqimtiaz ... There are also parameters with $$ prefix. IMO they have the same problem.

@Jermolene ... Can you remember, why you did restrict this.computeAttribute for the genesis-widget in the first run?

[Jermolene]

@Jermolene ... Can you remember, why you did restrict this.computeAttribute for the genesis-widget in the first run?

Yes, the reason it is done is because we only want to compute the values of the attributes that are actually used by the genesis widget itself. We handle the other attributes that are to be passed directly onto the created widget by copying the parse tree nodes themselves. The values of those attributes will be computed when that created widget is instantiated.

In other words, it is to avoid computing an expensive filtered attribute twice.