[webkit-dev] Platform improvements to the layout tests

[Matt Lilek]

Hi everybody,

We've recently made some changes to the layout tests that allow us to  
have much better flexibility in the way we handle platforms.  Most of  
my examples use Leopard only to demonstrate the hierarchical nature  
of the new tests and apply equally to all platforms.

Test results are now searched for using a platform hierarchy defined  
within the script for your platform.  If you were running Leopard for  
example, when run-webkit-tests comes across the css1/basic/ 
inheritance.html test, it will first search platform/mac-leopard/css1/ 
basic for the results, then platform/mac/css1/basic and finally in  
the same directory as the test.

As for new tests, if the test produces text-based results (ie: dom/),  
it will still have it's results generated alongside the test.

Pixel and render-tree test results will now be generated in the  
test's most common corresponding platform/ directory.  So creating a  
new test in fast/backgrounds on Leopard will have the results  
generated in platform/mac/fast/backgrounds.  If that test's results  
are specific to Leopard, they will manually have to be moved to the  
mac-leopard directory and a different set of results created on Tiger  
(or the test could just be made Leopard-only).  The mac pixel test  
results are still in their old locations, but I'll be migrating those  
to platform/mac as time goes on.

run-webkit-tests also now allows for platform-specific tests and  
Skipped files as well.  The addition of the former should hopefully  
cut down on the number of entries in the latter.

For those working on new ports, setting up all of this for your port  
is really easy.  Once you have DRT up and running, you only need to  
create your directory (or directories) in platform/ and define the  
$platform variable in run-webkit-tests to point to it.

Hopefully this clears up any confusion anyone may have.  Happy hacking!

- Matt