Support ES2015 Computed Property Names

[p-bakker]

Case just to track this specific ES6 feature (and how hard can it be to implement :-) ) and also because some tests in Test262 are disabled because they use this feature (and thus we cannot run them)

var name = 'myPropertyName';

Object.keys({
   [x] = 'someValue';
})[0] === name; // to yield true

[rPraml]

I've tried it here FOCONIS@98ef815 but I was lost in the ByteCode-generation for different optimization levels. Some tests will run, but some trigger a Kit.codeBug

[tuchida]

I tried to implement this in the past, but I think it was difficult to evaluate them in the proper order.
https://github.com/tuchida/rhino/commit/0fef518cbecfb9fd5fdd9703216b0dec184975f9

var obj = {
  [exp1]: exp2,
  "str1": exp3,
  [exp4]: exp5
};

[p-bakker]

Great to see there are already 2 attempts underway, guess I shouldn't start a third :-)

Any thoughts on which one seems to be more feasible? Both seem to take quite a different approach. Just by quickly browsing through the changes (for just the interpreted impl.) in either branch, it seems @rPraml 's approach has a lot smaller footprint (but no idea though if it covers all angles)

FYI: think in both branches, this feature exclusion in Test262SuiteTest should also be removed: https://github.com/mozilla/rhino/blob/master/testsrc/org/mozilla/javascript/tests/Test262SuiteTest.java#L78

[tuchida]

I don't have any plans to move forward with the implementation right now, as it is a long time ago on my branch.

[trajano]

Perhaps something akin to the babel transform can be used.