• rossberg@chromium.org's avatar
    Upgrade Symbol implementation to match current ES6 behavior. · 0d34254f
    rossberg@chromium.org authored
    Refresh the implementation of Symbols to catch up with what the
    specification now mandates:
    
    * The global Symbol() function manufactures new Symbol values,
      optionally with a string description attached.
    
    * Invoking Symbol() as a constructor will now throw.
    
    * ToString() over Symbol values still throws, and
      Object.prototype.toString() stringifies like before.
    
    * A Symbol value is wrapped in a Symbol object either implicitly if
      it is the receiver, or explicitly done via Object(symbolValue) or
      (new Object(symbolValue).)
    
    * The Symbol.prototype.toString() method no longer throws on Symbol
      wrapper objects (nor Symbol values.) Ditto for Symbol.prototype.valueOf().
    
    * Symbol.prototype.toString() stringifies as "Symbol("<description>"),
      valueOf() returns the wrapper's Symbol value.
    
    * ToPrimitive() over Symbol wrapper objects now throws.
    
    Overall, this provides a stricter separation between Symbol values and
    wrapper objects than before, and the explicit fetching out of the
    description (nee name) via the "name" property is no longer supported
    (by the spec nor the implementation.)
    
    Adjusted existing Symbol test files to fit current, adding some extra
    tests for new/changed behavior.
    
    LOG=N
    R=arv@chromium.org, rossberg@chromium.org, arv, rossberg
    BUG=v8:3053
    
    Review URL: https://codereview.chromium.org/118553003
    
    Patch from Sigbjorn Finne <sigbjornf@opera.com>.
    
    git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19490 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
    0d34254f
runtime.js 19.6 KB