[webkit-dev] LayoutTests results fallback graph

[Adam Barth]

On Sun, Jul 10, 2011 at 1:26 PM, Mark Rowe <mrowe at apple.com> wrote:
> On 2011-07-10, at 13:20, Adam Barth wrote:
>> Sure.  I'll highlight the relevant section of my original email:
>>
>> On Sun, Jul 10, 2011 at 10:52 AM, Adam Barth <abarth at webkit.org> wrote:
>>> These changes have the following virtues:
>>>
>>> A) The resulting fallback graph will be a tree, making the fallback
>>> graph easier to understand for both humans and automated tools.
>
> I don't see how Windows falling back to mac-snowleopard has any effect on that.  It's no different than mac-leopard in that regard.  Then again, maybe the diagram is trying to convey something that I'm missing due to having no idea what the difference is between the myriad of different line styles in the diagram.

Notice that the circle for "win" has two arrows emanating from it.
One of those arrows goes to "mac" and the other goes to
"mac-snowleopard".  That means that of the fallback paths that transit
"win", one path flows through "mac-snowlepard" where as the remainder
flow through "mac".  If we change "win" to fall back to "mac", then
the graph becomes more tree-like.  (If make change (2) as well, then
the graph globally becomes a tree.)

Having the fallback graph not be a tree causes some strange and
confusing anomalies, which I'd be happy to explain if you don't see
the value in using a fallback tree rather than a fallback DAG.

Adam