Fixing over-presumptive e.button assignment e.which was assigned with the button code if it wasn't undefined. Unfortunately, IE assigns e.button = 0 for *key* events, which isn't undefined, so it clobbered the e.keyCode assignment. e.which now uses e.keyCode if it's truthy, then falls back to a mapped e.button code, then to e.button. Collateral damage: e.button is assigned for key events now, since e.button is also mirrored on e.which. Take away: just use e.which for keys and mouse events.

Remove some useless logic from LazyEventFacade LazyEventFacade is only supported for IE8, which doesn't expose e.charCode or e.which for key events, so there's no need to reference them, or even populate the facade properties lazily.

Fix e.button regression from 3.2.0->3.3.0 Commit 8d1736f6000b6c7657192d7bc13a23e374fed77b caused e.button to report undefined in IE 6-8. Better to use mouseup for button determination anyway, but this is still a regression.

Add fallback for e.relatedTarget for simulated events IE doesn't allow setting e.toElement or e.fromElement on generic events, so Y.Event.simulate populates e.relatedTarget instead. So first check the real life properties, then fall back to the simulated compromise. This is mainly to facilitate automated testing.

Use Y.config.lazyEventFacad for realz The config was hard coded to true to facilitate testing against all automated test suites without having to modify them all.

Add support for YUI config lazyEventFacade (IE8 only) Initial foray into leveraging Object.defineProperty when setting up event facades so properties whose values involve some complicated setup get get the benefit of delaying the setup logic until the property is accessed. Involves setting up a proxy object (a native, simulated event) because IE8 only supports Object.defineProperty used with DOM objects. Keep an eye out for some work in the sandbox to leverage this same technique for Chrome, Safari, and Firefox 3.0+. Important note: since the object must be a DOM object, it will no longer be instanceof Y.DOMEventFacade and the object cannot be stored for later value retrieval, since IE invalidates event objects at the end of the JS thread of execution.

tweaked event conditional module logic

hasFeature update for IE event conditional module (for IE9) [fixes bug #2529587].

key events have the charCode assigned to the event facade's 'which' [fixes #2528975].

e.button and e.which normalized to 1/2/3 for l/m/r buttons respectively. Didn't normalize e.button to 0/1/2 (which may be more correct) because it would break existing implementations [fixes #2529140].

Fixed memory leak when adding a listener to an element that is never inserted into the dom [fixes #2529385]. Added a conditional module for IE. Faster event facades.

Fixed memory leak when adding a listener to an element that is never inserted into the dom [fixes #2529385]. Added a conditional module for IE. Faster event facades.