improve collections polyfills - O(1) and prevent possible leaking wit…

…h frozen keys, correct observable state for object keys, close #134

library/modules/_collection-strong.js

@@ -8,28 +8,10 @@ var $            = require('./_')
   , forOf        = require('./_for-of')
   , $iterDefine  = require('./_iter-define')
   , step         = require('./_iter-step')
-  , ID           = require('./_uid')('id')
-  , $has         = require('./_has')
-  , isObject     = require('./_is-object')
   , setSpecies   = require('./_set-species')
   , DESCRIPTORS  = require('./_descriptors')
-  , isExtensible = Object.isExtensible || isObject
-  , SIZE         = DESCRIPTORS ? '_s' : 'size'
-  , id           = 0;
-
-var fastKey = function(it, create){
-  // return primitive with prefix
-  if(!isObject(it))return typeof it == 'symbol' ? it : (typeof it == 'string' ? 'S' : 'P') + it;
-  if(!$has(it, ID)){
-    // can't set id to frozen object
-    if(!isExtensible(it))return 'F';
-    // not necessary to add id
-    if(!create)return 'E';
-    // add missing object id
-    hide(it, ID, ++id);
-  // return object id with prefix
-  } return 'O' + it[ID];
-};
+  , fastKey      = require('./_meta').fastKey
+  , SIZE         = DESCRIPTORS ? '_s' : 'size';
 
 var getEntry = function(that, key){
   // fast case

library/modules/_collection-weak.js

@@ -1,40 +1,38 @@
 'use strict';
-var hide              = require('./_hide')
-  , redefineAll       = require('./_redefine-all')
+var redefineAll       = require('./_redefine-all')
+  , getWeak           = require('./_meta').getWeak
   , anObject          = require('./_an-object')
   , isObject          = require('./_is-object')
   , strictNew         = require('./_strict-new')
   , forOf             = require('./_for-of')
   , createArrayMethod = require('./_array-methods')
   , $has              = require('./_has')
-  , WEAK              = require('./_uid')('weak')
-  , isExtensible      = Object.isExtensible || isObject
   , arrayFind         = createArrayMethod(5)
   , arrayFindIndex    = createArrayMethod(6)
   , id                = 0;
 
-// fallback for frozen keys
-var frozenStore = function(that){
+// fallback for uncaught frozen keys
+var uncaughtFrozenStore = function(that){
   return that._l || (that._l = new FrozenStore);
 };
-var FrozenStore = function(){
+var UncaughtFrozenStore = function(){
   this.a = [];
 };
-var findFrozen = function(store, key){
+var findUncaughtFrozen = function(store, key){
   return arrayFind(store.a, function(it){
     return it[0] === key;
   });
 };
-FrozenStore.prototype = {
+UncaughtFrozenStore.prototype = {
   get: function(key){
-    var entry = findFrozen(this, key);
+    var entry = findUncaughtFrozen(this, key);
     if(entry)return entry[1];
   },
   has: function(key){
-    return !!findFrozen(this, key);
+    return !!findUncaughtFrozen(this, key);
   },
   set: function(key, value){
-    var entry = findFrozen(this, key);
+    var entry = findUncaughtFrozen(this, key);
     if(entry)entry[1] = value;
     else this.a.push([key, value]);
   },
@@ -52,35 +50,34 @@ module.exports = {
     var C = wrapper(function(that, iterable){
       strictNew(that, C, NAME);
       that._i = id++;      // collection id
-      that._l = undefined; // leak store for frozen objects
+      that._l = undefined; // leak store for uncaught frozen objects
       if(iterable != undefined)forOf(iterable, IS_MAP, that[ADDER], that);
     });
     redefineAll(C.prototype, {
       // 23.3.3.2 WeakMap.prototype.delete(key)
       // 23.4.3.3 WeakSet.prototype.delete(value)
       'delete': function(key){
         if(!isObject(key))return false;
-        if(!isExtensible(key))return frozenStore(this)['delete'](key);
-        return $has(key, WEAK) && $has(key[WEAK], this._i) && delete key[WEAK][this._i];
+        var data = getWeak(key);
+        if(data === true)return uncaughtFrozenStore(this)['delete'](key);
+        return data && $has(data, this._i) && delete data[this._i];
       },
       // 23.3.3.4 WeakMap.prototype.has(key)
       // 23.4.3.4 WeakSet.prototype.has(value)
       has: function has(key){
         if(!isObject(key))return false;
-        if(!isExtensible(key))return frozenStore(this).has(key);
-        return $has(key, WEAK) && $has(key[WEAK], this._i);
+        var data = getWeak(key);
+        if(data === true)return uncaughtFrozenStore(this).has(key);
+        return data && $has(data, this._i);
       }
     });
     return C;
   },
   def: function(that, key, value){
-    if(!isExtensible(anObject(key))){
-      frozenStore(that).set(key, value);
-    } else {
-      $has(key, WEAK) || hide(key, WEAK, {});
-      key[WEAK][that._i] = value;
-    } return that;
+    var data = getWeak(anObject(key), true);
+    if(data === true)uncaughtFrozenStore(that).set(key, value);
+    else data[that._i] = value;
+    return that;
   },
-  frozenStore: frozenStore,
-  WEAK: WEAK
+  ufstore: uncaughtFrozenStore
 };

library/modules/_collection.js

@@ -2,6 +2,7 @@
 var $              = require('./_')
   , global         = require('./_global')
   , $export        = require('./_export')
+  , meta           = require('./_meta')
   , fails          = require('./_fails')
   , hide           = require('./_hide')
   , redefineAll    = require('./_redefine-all')
@@ -23,6 +24,7 @@ module.exports = function(NAME, wrapper, methods, common, IS_MAP, IS_WEAK){
     // create collection constructor
     C = common.getConstructor(wrapper, NAME, IS_MAP, ADDER);
     redefineAll(C.prototype, methods);
+    meta.NEED = true;
   } else {
     C = wrapper(function(target, iterable){
       strictNew(target, C, NAME);

library/modules/_meta.js

@@ -0,0 +1,53 @@
+var META     = require('./_uid')('meta')
+  , isObject = require('./_is-object')
+  , has      = require('./_has')
+  , setDesc  = require('./_').setDesc
+  , id       = 0;
+var isExtensible = Object.isExtensible || function(){
+  return true;
+};
+var FREEZE = !require('./_fails')(function(){
+  return isExtensible(Object.preventExtensions({}));
+});
+var setMeta = function(it){
+  setDesc(it, META, {value: {
+    i: 'O' + ++id, // object ID
+    w: {}          // weak collections IDs
+  }});
+};
+var fastKey = function(it, create){
+  // return primitive with prefix
+  if(!isObject(it))return typeof it == 'symbol' ? it : (typeof it == 'string' ? 'S' : 'P') + it;
+  if(!has(it, META)){
+    // can't set metadata to uncaught frozen object
+    if(!isExtensible(it))return 'F';
+    // not necessary to add metadata
+    if(!create)return 'E';
+    // add missing metadata
+    setMeta(it);
+  // return object ID
+  } return it[META].i;
+};
+var getWeak = function(it, create){
+  if(!has(it, META)){
+    // can't set metadata to uncaught frozen object
+    if(!isExtensible(it))return true;
+    // not necessary to add metadata
+    if(!create)return false;
+    // add missing metadata
+    setMeta(it);
+  // return hash weak collections IDs
+  } return it[META].w;
+};
+// add metadata on freeze-family methods calling
+var onFreeze = function(it){
+  if(FREEZE && meta.NEED && isExtensible(it) && !has(it, META))setMeta(it);
+  return it;
+};
+var meta = module.exports = {
+  KEY:      META,
+  NEED:     false,
+  fastKey:  fastKey,
+  getWeak:  getWeak,
+  onFreeze: onFreeze
+};

library/modules/es6.object.freeze.js

@@ -1,8 +1,9 @@
 // 19.1.2.5 Object.freeze(O)
-var isObject = require('./_is-object');
+var isObject = require('./_is-object')
+  , meta     = require('./_meta').onFreeze;
 
 require('./_object-sap')('freeze', function($freeze){
   return function freeze(it){
-    return $freeze && isObject(it) ? $freeze(it) : it;
+    return $freeze && isObject(it) ? $freeze(meta(it)) : it;
   };
 });

library/modules/es6.object.prevent-extensions.js

@@ -1,8 +1,9 @@
 // 19.1.2.15 Object.preventExtensions(O)
-var isObject = require('./_is-object');
+var isObject = require('./_is-object')
+  , meta     = require('./_meta').onFreeze;
 
 require('./_object-sap')('preventExtensions', function($preventExtensions){
   return function preventExtensions(it){
-    return $preventExtensions && isObject(it) ? $preventExtensions(it) : it;
+    return $preventExtensions && isObject(it) ? $preventExtensions(meta(it)) : it;
   };
 });

library/modules/es6.object.seal.js

@@ -1,8 +1,9 @@
 // 19.1.2.17 Object.seal(O)
-var isObject = require('./_is-object');
+var isObject = require('./_is-object')
+  , meta     = require('./_meta').onFreeze;
 
 require('./_object-sap')('seal', function($seal){
   return function seal(it){
-    return $seal && isObject(it) ? $seal(it) : it;
+    return $seal && isObject(it) ? $seal(meta(it)) : it;
   };
 });

library/modules/es6.symbol.js

@@ -6,6 +6,7 @@ var $              = require('./_')
   , DESCRIPTORS    = require('./_descriptors')
   , $export        = require('./_export')
   , redefine       = require('./_redefine')
+  , META           = require('./_meta').KEY
   , $fails         = require('./_fails')
   , shared         = require('./_shared')
   , setToStringTag = require('./_set-to-string-tag')
@@ -100,7 +101,7 @@ var $getOwnPropertyNames = function getOwnPropertyNames(it){
     , result = []
     , i      = 0
     , key;
-  while(names.length > i)if(!has(AllSymbols, key = names[i++]) && key != HIDDEN)result.push(key);
+  while(names.length > i)if(!has(AllSymbols, key = names[i++]) && key != HIDDEN && key != META)result.push(key);
   return result;
 };
 var $getOwnPropertySymbols = function getOwnPropertySymbols(it){

library/modules/es6.weak-map.js

@@ -1,40 +1,52 @@
 'use strict';
-var $            = require('./_')
+var each         = require('./_').each
   , redefine     = require('./_redefine')
+  , getWeak      = require('./_meta').getWeak
+  , assign       = require('./_object-assign')
   , weak         = require('./_collection-weak')
   , isObject     = require('./_is-object')
   , has          = require('./_has')
-  , frozenStore  = weak.frozenStore
-  , WEAK         = weak.WEAK
-  , isExtensible = Object.isExtensible || isObject
-  , tmp          = {};
+  , isExtensible = Object.isExtensible
+  , uncaughtFrozenStore = weak.ufstore
+  , tmp          = {}
+  , InternalMap;
 
-// 23.3 WeakMap Objects
-var $WeakMap = require('./_collection')('WeakMap', function(get){
-  return function WeakMap(){ return get(this, arguments.length > 0 ? arguments[0] : undefined); };
-}, {
+var wrapper = function(get){
+  return function WeakMap(){
+    return get(this, arguments.length > 0 ? arguments[0] : undefined);
+  };
+};
+
+var methods = {
   // 23.3.3.3 WeakMap.prototype.get(key)
   get: function get(key){
     if(isObject(key)){
-      if(!isExtensible(key))return frozenStore(this).get(key);
-      if(has(key, WEAK))return key[WEAK][this._i];
+      var data = getWeak(key);
+      if(data === true)return uncaughtFrozenStore(this).get(key);
+      return data ? data[this._i] : undefined;
     }
   },
   // 23.3.3.5 WeakMap.prototype.set(key, value)
   set: function set(key, value){
     return weak.def(this, key, value);
   }
-}, weak, true, true);
+};
+
+// 23.3 WeakMap Objects
+var $WeakMap = require('./_collection')('WeakMap', wrapper, methods, weak, true, true);
 
 // IE11 WeakMap frozen keys fix
 if(new $WeakMap().set((Object.freeze || Object)(tmp), 7).get(tmp) != 7){
-  $.each.call(['delete', 'has', 'get', 'set'], function(key){
+  InternalMap = weak.getConstructor(wrapper);
+  assign(InternalMap.prototype, methods);
+  each.call(['delete', 'has', 'get', 'set'], function(key){
     var proto  = $WeakMap.prototype
       , method = proto[key];
     redefine(proto, key, function(a, b){
-      // store frozen objects on leaky map
+      // store frozen objects on internal weakmap shim
       if(isObject(a) && !isExtensible(a)){
-        var result = frozenStore(this)[key](a, b);
+        if(!this._f)this._f = new InternalMap;
+        var result = this._f[key](a, b);
         return key == 'set' ? this : result;
       // store all the rest on native weakmap
       } return method.call(this, a, b);

modules/_collection-strong.js

@@ -8,28 +8,10 @@ var $            = require('./_')
   , forOf        = require('./_for-of')
   , $iterDefine  = require('./_iter-define')
   , step         = require('./_iter-step')
-  , ID           = require('./_uid')('id')
-  , $has         = require('./_has')
-  , isObject     = require('./_is-object')
   , setSpecies   = require('./_set-species')
   , DESCRIPTORS  = require('./_descriptors')
-  , isExtensible = Object.isExtensible || isObject
-  , SIZE         = DESCRIPTORS ? '_s' : 'size'
-  , id           = 0;
-
-var fastKey = function(it, create){
-  // return primitive with prefix
-  if(!isObject(it))return typeof it == 'symbol' ? it : (typeof it == 'string' ? 'S' : 'P') + it;
-  if(!$has(it, ID)){
-    // can't set id to frozen object
-    if(!isExtensible(it))return 'F';
-    // not necessary to add id
-    if(!create)return 'E';
-    // add missing object id
-    hide(it, ID, ++id);
-  // return object id with prefix
-  } return 'O' + it[ID];
-};
+  , fastKey      = require('./_meta').fastKey
+  , SIZE         = DESCRIPTORS ? '_s' : 'size';
 
 var getEntry = function(that, key){
   // fast case