Hi! 

I wrote a new test:
---
ROHorizontalLineLayoutTest>>testStretch

| previous |
ROHorizontalLineLayout new stretch; on: elements.
previous := nil.
elements do: [ :el |
previous notNil ifTrue: [ self assert: el position x > previous position x ].
previous := el ].
---

It is the same like ROHorizontalLineLayoutTest>>testLayout. I added #stretch on the first command.

Should it work? It breaks in the message ROHorizontalLineLayout>>doStretchHorizontal:, because it expect aGraph and ask for "aGraph bounds" and others. It obtains a collection of elements. Right now I do not understand what aGraph it should obtain.

Thanks for any advise,
Jura