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2419f7638c
So. It turns out that the design of SurfaceFragment is a little - shall we say - wonky. One of the best things about ve.dm.SurfaceFragment is its magical ability to retain the intention of its range, even as transactions are being processed. This ability is granted by each fragment listening to the surface's change event, and responding by using translateRange for each transaction that gets processed. Surface fragments also have these clever methods that allow you to get a fragment based on another, which makes adjusting the range easy to do inline without having to manually store multiple fragments or modifying the original. This sounded good, and we seemed to all be convinced it was well designed. But if you add a console.log( 'hello' ); to the first line of ve.dm.SurfaceFragment.prototype.onTransact, and then start using the bold tool on various selections of text, you will find that there may indeed be a flaw. What you will probably realize is that the number of times that particular line of code is being called is disturbingly large, and increases each time you do just about anything in the editor. What's going on? How did we get here? Read on… It turns out that fragments are immortal. We create them, they listen to the surface's transact event, we are done with them, but the surface keeps on emitting events to the now long forgotten about fragments. They continue to build up over time, never go out of scope, and bloat the hell out of our program. The same ended up being true of toolbars - and each time the context menu fired up a new one the old one was left in limbo, still responding to events, still taking up memory, but not being visible to the user. All of this immortality was causing strange and difficult to track down problems. This patch fixes this by introducing a destroy method. This method unbinds events, allowing the object to finally fall out of scope and die - and more importantly stop receiving notifications of changes. This is a hack, but Ed will no doubt get this situation sorted out properly by making fragments lazy-evaluate their selections by only storing an identifier of the most recent transaction they were based on, see bug 47343. Change-Id: I18bb986001a44732a7871b9d79dc3015eedfb168 |
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ve.ui.LinkInspector.js | ||
ve.ui.MWLinkInspector.js |