[webkit-dev] embedding pixel result checksum in the png

Tony Chang tony at chromium.org
Tue Apr 5 12:11:17 PDT 2011

I propose that we move away from checking in separate .checksum files for
pixel tests and instead embed the checksum in the .png file as a comment.

There are two main benefits of doing this:
1) Less files in the tree -> faster git/svn operations.  Currently, in
LayoutTests, 32,650 out of 141,170 files are checksum files (23% of the
2) Less likely to accidentally check in a .checksum without a .png or a .png
without a .checksum.

We're currently trying this out in the Chromium port, but I would like to
add this to the other ports as well.

To make embedded checksums easier to use, I've added a
script Tools/Scripts/read-checksum-from-png that will read the checksum from
a png file passed in on the command line.  I've also updated the flakiness
dashboard and plan on updating PrettyPrint.rb so you can see the checksums
in a diff.  If there are other tools or workflows that might be interrupted
by this change, please let me know and I will update those tools as well.

If there are no objections to this, my plan is as follows:
a) Update DRT to write the checksum to png files.
b) Update run-webkit-tests to read the checksum from png files if the
.checksum file is absent.
c) Update webkit-patch rebaseline to not copy over the .checksum file.
d) Update run-webkit-tests --reset-results and --new-baseline to not write
.checksum files.
e) Start converting old results to the new format (i.e., put the checksum in
the png and delete the .checksum file).

Thoughts or suggestions for improvement?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-dev/attachments/20110405/05fa5bdd/attachment.html>

More information about the webkit-dev mailing list