640270 - Can ScriptObject::defaultValue() and toString() be non virtual?

Status: RESOLVED WONTFIX

(Tamarin Graveyard :: Virtual Machine, defect)

Description

[Edwin Smith]

Alternatively, (maybe), the guts of those methods should be factored out so that the type guarantees can be assumed by JIT callers.  e.g. guarantees that toString() returns a non-null String, and defaultValue() returns a non-object value.

Comment 1

[Steven Johnson]

toString() is only a handful of places: APXHostObjectGlue/FPXHostObjectGlue (used by APE and authplay), and URLStreamGlue, oddly enough. The first two could probably be elided easily enough, but URLStreamGlue probably needs to stay.

defaultValue() is overridden only once, but that's in JavaScriptBaseObject, the root of AIR's AS<->JS bridge. Adding ChrisB.

Comment 2

[Christopher A. Brichford]

When the object is a javascript object, we need to use the javascript engine's version of defaultValue.  As I've said before the JS bridge needs to be able to create Object's, Function's, and Array's that have *all* of their operations forwarded to the java script engine.  defaultValue is an operation defined by ecma script.  See section 8.6.2 of http://www.ecma-international.org/publications/files/ECMA-ST/ECMA-262.pdf

Comment 3

[Edwin Smith]

These can stay virtual or move to another place in ANI with the same capability, if the VM wrapper around them can enforce the invariants that we want to enforce (and which ECMA-262 says are the case), described above.

Comment 4

[Steven Johnson]

Hmm... since the default implementations simply call the AS3 implementation, simplest would be to have the few use cases override it in AS3.

Comment 5

[Sylvestre Ledru [:Sylvestre]]

Tamarin isn't maintained anymore. WONTFIX remaining bugs.