Hello,
Yesterday I have updated the Jenkins jobs running PHPUnit to enable $wgDebugLogFile and provide the result in the build result. That will hopefully help people figuring what is wrong when a test is failing.
As an example, the VisualEditor extension as a qunit job. It uses phantomjs (a headless browser) to run the Javascript QUnit tests against a MediaWiki wiki installed locally. A run example is:
https://integration.wikimedia.org/ci/job/mwext-VisualEditor-qunit/5212/
On that page you will see links to files that have been archived:
Build Artifacts LocalSettings.php 6.16 KB mw-debug-cli.log.gz 340 B mw-debug-www.log.gz 1.55 KB
The LocalSettings.php is the full configuration for that change. It is crafted using the maintenance/installer.php and appending configuration files hosted in integration/jenkins.git under /mediawiki/conf.d/ :
http://git.wikimedia.org/tree/integration%2Fjenkins.git/master/mediawiki%2Fc...
mw-debug-cli.log.gz is the $wgDebugLogFile whenever we have $wgCommandLineMode mw-debug-www.log.gz is the $wgDebugLogFile from the Apache hits.
That new feature is NOT enabled yet for mediawiki/core.
Happy testing!