[CDash] How to debug missing dart images in dash

[Nyall Dawson]

Hi CDash devs,

I'm currently hitting an issue I can't resolve with submission of
ctest results to cdash. Our project makes heavy use of
DartMeasurementFile to display expected/rendered image results on
cdash. This works fine for most set ups, and images are correctly
displayed on our dash (eg, see
http://dash.orfeo-toolbox.org/testDetails.php?test=39250586&build=222727
).

However, we've recently deployed a new build on Travis which makes use
of cmake version 3.5, and using this build we cannot get the dart
measurement files to display. An example output is
http://dash.orfeo-toolbox.org/testDetails.php?test=39284628&build=222801
. The test code has not changed, and the same DartMeasurementFile
messages are being output by the tests, but they are just ignored by
ctest/cdash and we do not see the images for these builds.

I've spent some time trying to debug this, but I'm stumped. Is there
anything different with cmake 3.5 which would explain this behaviour?

Kind regards,
Nyall