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Engineering department restructured; "break MediaWiki and be reverted"; news in brief

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By Jarry1250

Engineering department restructured

According to Deputy Director of the Wikimedia Foundation Erik Möller, the foundation's Engineering Department will be reorganised with immediate effect. The department, which handles the technical side of the WMF's operations, will now be split into four sub-departments (wikitech-l):

These four departments will be augmented by three special "architect" roles, representing "an additional career path for our distinguished engineers beyond 'become a manager'". Two new roles will therefore be created to accompany the existing position of Lead Software Architect held by newly returned ex-CTO Brion Vibber: Lead Operations Architect (Mark Bergsma) and Lead Platform Architect (Tim Starling). Möller also acknowledged the current positions of Senior Product Manager (held by Howie Fung) and Senior Research Analyst (Dario Taraborelli) to help the Engineering Department to integrate with other stakeholders in the wider movement.

Möller added that he will be taking on the role of overall head of the Engineering Department, at least on a temporary basis. As such, no new CTO will be recruited to replace Danese Cooper, who announced her resignation a fortnight ago (see previous Signpost coverage).

Developers told: "break it and be reverted"

In theory, all changes to the MediaWiki software should be run against an automated test suite, incorporating parser tests, unit tests (tests of individual actions, such as page deletions); since May's Berlin Hackathon, this list has included JavaScript tests. However, in practice MediaWiki has not run as tight a ship as some of its larger counterparts such as Mozilla. For example, before October last year, the system for automating parser tests was considered broken. When that system was replaced in favour of an automated test system known as "CruiseControl" (implemented as part of the phpUnderControl suite), hopes were high that MediaWiki could move to a more rigorous system of speedily reverting any changes that broke the software. Nonetheless, the system immediately suffered from the fact that tests took so long to run that the results were out of date by the time of their publication. In May this year the decision was announced to exclude these long-running tests. Even so, though tests were now quicker, the consistent failure of a number of tests hurt the ideal of a fast revert for all bad code.

On 15 June, developer Chad Horohoe announced that work on reducing the number of permanently failing tests to zero had been successful (wikitech-l mailing list). This has delivered two benefits: firstly, it means that the current bleeding edge code (known as trunk) is free of the many bugs tested for by the suite (check its current status). Secondly, if a test fails in the future, it will be possible to pinpoint the revisions that broke the software, and revert them or otherwise fix the problem within minutes. "From here on out", wrote Horohoe, "I'm going to take the stance that if you break a test, it must be fixed or reverted on sight". Those who follow the MediaWiki development cycle will no doubt hope that this will significantly reduce the time needed to get code from trunk to production, and so help MediaWiki towards a faster release cycle. In a separate announcement, developer User:Krinkle noted that a parallel set of JavaScript-based tests are now also functioning (also wikitech-l).

In brief

Not all fixes may have gone live to WMF sites at the time of writing; some may not be scheduled to go live for many weeks.

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As far as i know, the parser Tests never were (And still aren't) considered broken. It was the automated system that ran them and uploaded the results to mw:special:code that was broken. Of course, the newer Phpunit test's of course have more scope then the plain old parser tests. Bawolff (talk) 04:32, 22 June 2011 (UTC)[reply]
Yes, AFAIK, it was the system of parser tests that was broken, rather than the tests themselves. (I have reworded the article to make this clearer.)Parser tests obviously serve a very useful function :) The fact that a full range of unit tests is now available is a good thing nonetheless. - Jarry1250 [Weasel? Discuss.] 10:16, 22 June 2011 (UTC)[reply]


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