1037939 - `new Function()` args should be parsed as `FormalParameters`, supporting destructuring and defaults

Status: RESOLVED DUPLICATE of bug 755821

(Core :: JavaScript Engine, defect)

Description

[Arpad Borsos [:Swatinem]]

ES6 says:
> 19.2.1.1 Function ( p1, p2, … , pn, body )
> …
> Let P be the result of concatenating the previous value of P, the String "," (a comma), and nextArgString.
> …
> Let parameters be the result of parsing P, interpreted as UTF-16 encoded Unicode text as described in 10.1.1, using FormalParameters as the goal symbol. Throw a SyntaxError exception if the parse fails.

`FormalParameters` boils down to `BindingElement`.

This means that things like `new Function('{a,b}', 'return;')` should work. They currently dont:

```
js> new Function('a = 10','return;')
typein:33:0 SyntaxError: malformed formal parameter
js> new Function('{a,b}','return;')  
typein:34:0 SyntaxError: malformed formal parameter
js> new Function('[a,b]','return;') 
typein:35:0 SyntaxError: malformed formal parameter
```

(however, they already support rest and multiple params)
```
js> new Function('a,b','return;')   
(function anonymous(a, b) {
return;
})
js> new Function('...rest','return;')    
(function anonymous(...rest) {
return;
})
```

Comment 1

[André Bargull [:anba]]

Related to bug 755821