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
This replaces before_remove_attr(), after_remove_attr() and after_set_attr().
The virtual method takes the mutated attribute and an AttributeMutation value
to disambiguate between "attribute is changed", "attribute is added" and
"attribute is removed".
In the case of "attribute is changed", the mutation value contains a reference
to the old value of the mutated attribute, which is used to unregister outdated
named elements when the "id" attribute is changed on an element.
This greatly simplifies the handling of attributes, which in many cases don't
have any specific behaviour whether they are removed or changed or added. It
also fixes a few bugs where things were put in before_remove_attr() instead of
after_remove_attr() (e.g. when removing an href attribute from a base element).
A few helper functions in Element were also renamed and made private.
This virtual method mimics the behaviour of mutation observers and make it more
viable than the older child_inserted(), which didn't cover removed nodes and
was called as many times as there were inserted nodes.
A few other shortcomings where remove_child() was called directly instead of
Node::remove() were also fixed while at it.
Added support for the tabindex field, also added its correct defaults (-2 TODOs for things not supported in Servo yet). Also added tabindex logic into Element::is_focusable_area.
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This used to conflict with the util crate from the standard library, which
has long since been removed.
The import in layout has not been changed because of a conflict with the
util mod there.
Additionally, this patch cleans up some miscellaneous formatting issues
and refactors files in `layout/css/` somewhat to eliminate needless
levels of indirection. It also fixes our handling of presentational
hints that only apply if border is nonzero.
