Remove unnecessary uses of #[no_move]
The patch makes RootCollection a bit safer by making the StackRootTLS hold
it in place.
RootedVec was doing an extremely delicate dance and just hoping nobody
messed it up; switch to a Box to be safe.
CodeGenRust seemed to be using no_move for no particularly good reason.
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The patch makes RootCollection a bit safer by making the StackRootTLS hold
it in place.
The use of no_move in CodeGenRust was leftover from when roots couldn't
be moved.
Basically, instead of trying to check for specific kinds of statements,
just check the types of all local variables.
Also included are some commented-out proposals for some slightly more
aggressive lints which might be useful (but trigger a little too
frequently at the moment).
This trait is used to hold onto the downcast and upcast functions of all
castable IDL interfaces. A castable IDL interface is one which either derives
from or is derived by other interfaces.
The deriving relation is represented by implementations of marker trait
DerivedFrom<T: Castable> generated in InheritTypes.
/^[ ]*use dom::bindings::codegen::InheritTypes::.*(Base|Cast|Derived)/ {
/::[a-zA-Z]+(Base|Cast|Derived);/d
s/([{ ])[a-zA-Z]+(Base|Cast|Derived), /\1/g
s/([{ ])[a-zA-Z]+(Base|Cast|Derived), /\1/g
s/, [a-zA-Z]+(Base|Cast|Derived)([},])/\2/g
s/, [a-zA-Z]+(Base|Cast|Derived)([},])/\2/g
/\{([a-zA-Z]+(Base|Cast|Derived))?\};$/d
s/\{([a-zA-Z_]+)\};$/\1;/
}
s/([a-zA-Z]+)Cast::from_ref\(\&?\**([a-zA-Z_]+)(\.r\(\))?\)/\2.upcast::<\1>()/g
s/([a-zA-Z]+)Cast::from_ref\(\&?\**([a-zA-Z_]+)(\.[a-zA-Z_]+\(\))?\)/\2\3.upcast::<\1>()/g
s/\(([a-zA-Z]+)Cast::from_ref\)/\(Castable::upcast::<\1>\)/g
s/([a-zA-Z]+)Cast::from_root/Root::upcast::<\1>/g
s/([a-zA-Z]+)Cast::from_layout_js\(\&([a-zA-Z_.]+)\)/\2.upcast::<\1>()/g
s/([a-zA-Z]+)Cast::to_ref\(\&?\**([a-zA-Z_]+)(\.r\(\))?\)/\2.downcast::<\1>()/g
s/([a-zA-Z]+)Cast::to_ref\(\&?\**([a-zA-Z_]+)(\.[a-zA-Z_]+\(\))?\)/\2\3.downcast::<\1>()/g
s/\(([a-zA-Z]+)Cast::to_ref\)/\(Castable::downcast::<\1>\)/g
s/([a-zA-Z]+)Cast::to_root/Root::downcast::<\1>/g
s/([a-zA-Z]+)Cast::to_layout_js\(&?([a-zA-Z_.]+(\(\))?)\)/\2.downcast::<\1>()/g
s/\.is_document\(\)/.is::<Document>()/g
s/\.is_htmlanchorelement\(\)/.is::<HTMLAnchorElement>()/g
s/\.is_htmlappletelement\(\)/.is::<HTMLAppletElement>()/g
s/\.is_htmlareaelement\(\)/.is::<HTMLAreaElement>()/g
s/\.is_htmlbodyelement\(\)/.is::<HTMLBodyElement>()/g
s/\.is_htmlembedelement\(\)/.is::<HTMLEmbedElement>()/g
s/\.is_htmlfieldsetelement\(\)/.is::<HTMLFieldSetElement>()/g
s/\.is_htmlformelement\(\)/.is::<HTMLFormElement>()/g
s/\.is_htmlframesetelement\(\)/.is::<HTMLFrameSetElement>()/g
s/\.is_htmlhtmlelement\(\)/.is::<HTMLHtmlElement>()/g
s/\.is_htmlimageelement\(\)/.is::<HTMLImageElement>()/g
s/\.is_htmllegendelement\(\)/.is::<HTMLLegendElement>()/g
s/\.is_htmloptgroupelement\(\)/.is::<HTMLOptGroupElement>()/g
s/\.is_htmloptionelement\(\)/.is::<HTMLOptionElement>()/g
s/\.is_htmlscriptelement\(\)/.is::<HTMLScriptElement>()/g
s/\.is_htmltabledatacellelement\(\)/.is::<HTMLTableDataCellElement>()/g
s/\.is_htmltableheadercellelement\(\)/.is::<HTMLTableHeaderCellElement>()/g
s/\.is_htmltablerowelement\(\)/.is::<HTMLTableRowElement>()/g
s/\.is_htmltablesectionelement\(\)/.is::<HTMLTableSectionElement>()/g
s/\.is_htmltitleelement\(\)/.is::<HTMLTitleElement>()/g
We can only borrow JS<T> from rooted things, so it's safe to deref it.
The only types that provide mutable JS<T> things are MutHeap<JS<T>> and
MutNullableHeap<JS<T>>, which don't actually expose that they contain
JS<T> values.
get() must always return a rooted value, because we have no way of
ensuring the value won't be invalidated. set() takes an &T because it's
convenient; there isn't any need to expose JS<T>.
