Identify all non-EcmaScript behavior and extentions to disable/remove/make optional in v2.0.0

[p-bakker]

In v2.0.0 we want to, by default, run Rhino with Context.VERSION.ECMASCRIPT (see #1055), which should give the user a clean, EcmaScript compliant JavaScript engine, with, by default, no (api) extensions

In order to achieve that goal, all non-standard behavior and API extensions need to be identified

To aid in this, one of the goals for v1.7.15 is to be able to run the latest version of the Test262 suite, so we can get good feedback on how standard-compliant Rhino is. Note that standard-compliant doesn't necessarily mean feature completeness.

Test262 however doesn't not report on non-compliant API extensions, so those need to be identified through other means.

See the Next steps for Rhino after the v1.7.14 release discussion for already identified EcmaScript incompatibilities in Rhino

(incomplete) list of incompatibilites

• cases tagged with non-Ecma
• Nashorn Compatibility Script
• MDN New in JavaScript, for example Array Comprehensions
• Expression Closures
• Conditional catch clause
• Iterator()/iterator
• Legacy Generators: yield without *
• parent
• nosuchMethod
• proto
• .toSource
• uneval
• Properly disable everything related to E4X when E4X is turned off #990 for each in loops
• JavaAdapter syntax suger: a = new java.util.HashMap() { b: 1 }, alse see Next steps for Rhino after the v1.7.14 release #972 (reply in thread)

To get a more complete list, the followin steps could (should?) be taken:

• Try to get a definitive list of Objects with all their (class/instance/prototype) properties and compare that with what Rhino has at runtime. Not sure of such a list already exists, other than in the EcmaScript spec or maybe just the docs on MDN. Could try to scrape MDN or extract stuff from the EcmaScript spec
• go through https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features
• go through https://developer.mozilla.org/en-US/search?q=deprecated
• go through https://github.com/mdn/content/search?q=%7B%7Bdeprecated_header%7D%7D+path:files/en-us/web/javascript/
• Temporarily enable the annexb section in Test262 to see which tests pass, which should indicate Rhino supports things that are part of Annex B