As I recall it (it was ages since I dealt with this), the tricky case that you need to handle is this one:
http://software.hixie.ch/utilities/js/live-dom-viewer/?saved=2432 In this case, web compatibility requires that the <input> is associated with the form. Specifically hidden <input> elements would often end up moved, but still had to show up in form.elements as well as get submitted along with the form. / Jonas / Jonas On Tue, Aug 6, 2013 at 2:01 PM, Adam Klein <ad...@chromium.org> wrote: > Hixie opened my eyes last week to parser-association behavior of the > sort found at > http://software.hixie.ch/utilities/js/live-dom-viewer/?saved=2428. > In that case, an <input> in a detached tree is associated with a > <form> in the main document. This causes badness in WebKit and Blink > because the association between the <form> and the <input> (e.g., as > exposed in the HTMLFormElement.elements collection) is only weakly > held to avoid reference loops (and thus memory leaks). And that > weakness occasionally results in crashes when one of these objects is > collected before the other. > > While all modern HTML parser implementations I tested seemed to agree > on their treatment of the above example (they all return "1" as > elements.length), this feature doesn't strike me as terribly useful. > And for what it's worth, it doesn't seem to be present in legacy IE. > > I'm interested what others would think about changing the parser to > only associate a <form> with an <input> if both are in the same "home > subtree" > (http://www.whatwg.org/specs/web-apps/current-work/multipage/infrastructure.html#home-subtree). > Or is there some deep web-compat reason for this parsing oddity? > > - Adam