2 commits

Author	SHA1	Message	Date
Andreas Kling	8286f8b996	LibJS: Add property configuration transitions ... Object.defineProperty() can now change the attributes of a property already on the object. Internally this becomes a shape transition with the TransitionType::Configure. Such transitions don't expand the property storage capacity, but rather simply keep attributes up to date when generating a property table.	2020-04-10 00:36:06 +02:00
Andreas Kling	e6d920d87d	LibJS: Add Object.defineProperty() and start caring about attributes ... We now care (a little bit) about the "configurable" and "writable" property attributes. Property attributes are stored together with the property name in the Shape object. Forward transitions are not attribute-savvy and will cause poor Shape reuse in the case of multiple same-name properties with different attributes. Oh, and this patch also adds Object.getOwnPropertyDescriptor() :^)	2020-04-10 00:36:06 +02:00