From a5dcce876d40f2bce17886f6f7ecfad7dce9f7a2 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 14:04:26 -0400
Subject: [PATCH 01/39] DRY up meta()

---
 packages/ember-metal/lib/utils.js | 23 +++++++----------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/packages/ember-metal/lib/utils.js b/packages/ember-metal/lib/utils.js
index ac9f5f79109..9085a856955 100644
--- a/packages/ember-metal/lib/utils.js
+++ b/packages/ember-metal/lib/utils.js
@@ -328,27 +328,19 @@ function meta(obj, writable) {
     return ret || EMPTY_META;
   }
 
-  if (!ret) {
-    if (obj.__defineNonEnumerable) {
-      obj.__defineNonEnumerable(EMBER_META_PROPERTY);
-    } else {
-      Object.defineProperty(obj, '__ember_meta__', META_DESC);
-    }
+  if (obj.__defineNonEnumerable) {
+    obj.__defineNonEnumerable(EMBER_META_PROPERTY);
+  } else {
+    Object.defineProperty(obj, '__ember_meta__', META_DESC);
+  }
 
+  if (!ret) {
     ret = new Meta(obj);
 
     if (isEnabled('mandatory-setter')) {
       ret.values = {};
     }
-
-    obj.__ember_meta__ = ret;
   } else if (ret.source !== obj) {
-    if (obj.__defineNonEnumerable) {
-      obj.__defineNonEnumerable(EMBER_META_PROPERTY);
-    } else {
-      Object.defineProperty(obj, '__ember_meta__', META_DESC);
-    }
-
     ret = Object.create(ret);
     ret.watching  = Object.create(ret.watching);
     ret.cache     = undefined;
@@ -357,9 +349,8 @@ function meta(obj, writable) {
     if (isEnabled('mandatory-setter')) {
       ret.values = Object.create(ret.values);
     }
-
-    obj['__ember_meta__'] = ret;
   }
+  obj.__ember_meta__ = ret;
   return ret;
 }
 

From 8133291d3d1cc90297c490e20b711a0b90c693b5 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 15:04:29 -0400
Subject: [PATCH 02/39] moving meta into its own module

---
 packages/ember-metal/lib/main.js  |  8 ++-
 packages/ember-metal/lib/meta.js  | 93 +++++++++++++++++++++++++++++++
 packages/ember-metal/lib/utils.js | 93 +------------------------------
 3 files changed, 101 insertions(+), 93 deletions(-)
 create mode 100644 packages/ember-metal/lib/meta.js

diff --git a/packages/ember-metal/lib/main.js b/packages/ember-metal/lib/main.js
index e8d7a25ed97..d4a4f12d1ad 100644
--- a/packages/ember-metal/lib/main.js
+++ b/packages/ember-metal/lib/main.js
@@ -14,9 +14,7 @@ import {
   unsubscribe as instrumentationUnsubscribe
 } from 'ember-metal/instrumentation';
 import {
-  EMPTY_META,
   GUID_KEY,
-  META_DESC,
   apply,
   applyStr,
   canInvoke,
@@ -24,12 +22,16 @@ import {
   guidFor,
   inspect,
   makeArray,
-  meta,
   deprecatedTryCatchFinally,
   tryInvoke,
   uuid,
   wrap
 } from 'ember-metal/utils';
+import {
+  EMPTY_META,
+  META_DESC,
+  meta
+} from 'ember-metal/meta';
 import EmberError from 'ember-metal/error';
 import Cache from 'ember-metal/cache';
 import Logger from 'ember-metal/logger';
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
new file mode 100644
index 00000000000..60d75cf2780
--- /dev/null
+++ b/packages/ember-metal/lib/meta.js
@@ -0,0 +1,93 @@
+// Remove "use strict"; from transpiled module until
+// https://bugs.webkit.org/show_bug.cgi?id=138038 is fixed
+//
+'REMOVE_USE_STRICT: true';
+
+import isEnabled from 'ember-metal/features';
+
+/**
+@module ember-metal
+*/
+
+function Meta(obj) {
+  this.watching = {};
+  this.cache = undefined;
+  this.source = obj;
+  this.deps = undefined;
+  this.listeners = undefined;
+  this.mixins = undefined;
+  this.bindings = undefined;
+  this.chains = undefined;
+  this.chainWatchers = undefined;
+  this.values = undefined;
+  this.proto = undefined;
+}
+
+export var META_DESC = {
+  writable: true,
+  configurable: true,
+  enumerable: false,
+  value: null
+};
+
+var EMBER_META_PROPERTY = {
+  name: '__ember_meta__',
+  descriptor: META_DESC
+};
+
+// Placeholder for non-writable metas.
+export var EMPTY_META = new Meta(null);
+
+if (isEnabled('mandatory-setter')) {
+  EMPTY_META.values = {};
+}
+
+/**
+  Retrieves the meta hash for an object. If `writable` is true ensures the
+  hash is writable for this object as well.
+
+  The meta object contains information about computed property descriptors as
+  well as any watched properties and other information. You generally will
+  not access this information directly but instead work with higher level
+  methods that manipulate this hash indirectly.
+
+  @method meta
+  @for Ember
+  @private
+
+  @param {Object} obj The object to retrieve meta for
+  @param {Boolean} [writable=true] Pass `false` if you do not intend to modify
+    the meta hash, allowing the method to avoid making an unnecessary copy.
+  @return {Object} the meta hash for an object
+*/
+export function meta(obj, writable) {
+  var ret = obj.__ember_meta__;
+  if (writable === false) {
+    return ret || EMPTY_META;
+  }
+
+  if (obj.__defineNonEnumerable) {
+    obj.__defineNonEnumerable(EMBER_META_PROPERTY);
+  } else {
+    Object.defineProperty(obj, '__ember_meta__', META_DESC);
+  }
+
+  if (!ret) {
+    ret = new Meta(obj);
+
+    if (isEnabled('mandatory-setter')) {
+      ret.values = {};
+    }
+  } else if (ret.source !== obj) {
+    ret = Object.create(ret);
+    ret.watching  = Object.create(ret.watching);
+    ret.cache     = undefined;
+    ret.source    = obj;
+
+    if (isEnabled('mandatory-setter')) {
+      ret.values = Object.create(ret.values);
+    }
+  }
+  obj.__ember_meta__ = ret;
+  return ret;
+}
diff --git a/packages/ember-metal/lib/utils.js b/packages/ember-metal/lib/utils.js
index 9085a856955..c69d844e2c3 100644
--- a/packages/ember-metal/lib/utils.js
+++ b/packages/ember-metal/lib/utils.js
@@ -3,7 +3,7 @@
 //
 'REMOVE_USE_STRICT: true';
 
-import isEnabled from 'ember-metal/features';
+import { meta } from 'ember-metal/meta';
 
 /**
 @module ember-metal
@@ -139,18 +139,6 @@ var nullDescriptor = {
   value: null
 };
 
-var META_DESC = {
-  writable: true,
-  configurable: true,
-  enumerable: false,
-  value: null
-};
-
-export var EMBER_META_PROPERTY = {
-  name: '__ember_meta__',
-  descriptor: META_DESC
-};
-
 export var GUID_KEY_PROPERTY = {
   name: GUID_KEY,
   descriptor: nullDescriptor
@@ -280,79 +268,6 @@ export function guidFor(obj) {
   }
 }
 
-// ..........................................................
-// META
-//
-function Meta(obj) {
-  this.watching = {};
-  this.cache = undefined;
-  this.source = obj;
-  this.deps = undefined;
-  this.listeners = undefined;
-  this.mixins = undefined;
-  this.bindings = undefined;
-  this.chains = undefined;
-  this.chainWatchers = undefined;
-  this.values = undefined;
-  this.proto = undefined;
-}
-
-// Placeholder for non-writable metas.
-var EMPTY_META = new Meta(null);
-
-if (isEnabled('mandatory-setter')) {
-  EMPTY_META.values = {};
-}
-
-/**
-  Retrieves the meta hash for an object. If `writable` is true ensures the
-  hash is writable for this object as well.
-
-  The meta object contains information about computed property descriptors as
-  well as any watched properties and other information. You generally will
-  not access this information directly but instead work with higher level
-  methods that manipulate this hash indirectly.
-
-  @method meta
-  @for Ember
-  @private
-
-  @param {Object} obj The object to retrieve meta for
-  @param {Boolean} [writable=true] Pass `false` if you do not intend to modify
-    the meta hash, allowing the method to avoid making an unnecessary copy.
-  @return {Object} the meta hash for an object
-*/
-function meta(obj, writable) {
-  var ret = obj.__ember_meta__;
-  if (writable === false) {
-    return ret || EMPTY_META;
-  }
-
-  if (obj.__defineNonEnumerable) {
-    obj.__defineNonEnumerable(EMBER_META_PROPERTY);
-  } else {
-    Object.defineProperty(obj, '__ember_meta__', META_DESC);
-  }
-
-  if (!ret) {
-    ret = new Meta(obj);
-
-    if (isEnabled('mandatory-setter')) {
-      ret.values = {};
-    }
-  } else if (ret.source !== obj) {
-    ret = Object.create(ret);
-    ret.watching  = Object.create(ret.watching);
-    ret.cache     = undefined;
-    ret.source    = obj;
-
-    if (isEnabled('mandatory-setter')) {
-      ret.values = Object.create(ret.values);
-    }
-  }
-  obj.__ember_meta__ = ret;
-  return ret;
-}
 
 
 /**
@@ -584,9 +499,7 @@ export function applyStr(t, m, a) {
 
 export {
   GUID_KEY,
-  META_DESC,
-  EMPTY_META,
-  meta,
   makeArray,
-  canInvoke
+  canInvoke,
+  meta // this is temporary until I can refactor all the import sites
 };

From 30445476e4070444aa1f4c742807e3a86c62177c Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 15:11:26 -0400
Subject: [PATCH 03/39] make exports consistent

---
 packages/ember-metal/lib/events.js | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index 81646951566..13623428963 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -154,7 +154,7 @@ export function addListener(obj, eventName, target, method, once) {
   @param {Function|String} method A function or the name of a function to be called on `target`
   @public
 */
-function removeListener(obj, eventName, target, method) {
+export function removeListener(obj, eventName, target, method) {
   Ember.assert('You must pass at least an object and event name to Ember.removeListener', !!obj && !!eventName);
 
   if (!method && 'function' === typeof target) {
@@ -412,7 +412,3 @@ export function on(...args) {
   func.__ember_listens__ = events;
   return func;
 }
-
-export {
-  removeListener
-};

From ab2515359c51c701e7932a28e940c77c7bd335ca Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 16:33:18 -0400
Subject: [PATCH 04/39] notes-to-self on each meta property's access patterns

---
 packages/ember-metal/lib/meta.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 60d75cf2780..3ca5f96ce94 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -10,16 +10,46 @@ import isEnabled from 'ember-metal/features';
 */
 
 function Meta(obj) {
+  // map from strings to integer, with plain prototypical inheritance,
+  // cloned at meta creation.
   this.watching = {};
+
+  // plain map with no inheritance
   this.cache = undefined;
+
+  // used only internally by meta() to distinguish meta-from-prototype
+  // from instance's own meta
   this.source = obj;
+
+  // map of maps, with two-level prototypical inheritance, cloned on access
   this.deps = undefined;
+
+  // map from keys to lists. Has own __source__ property that's used
+  // to distinguish whether it is being inherited or not. Each list
+  // also has a __source__property. Both levels are inherited on
+  // demand with o_create.
   this.listeners = undefined;
+
+  // o_create inherited on demand
   this.mixins = undefined;
+
+  // o_create inherited on demand. May also get wiped out with a
+  // direct `m.bindings = {}` after they're handled.
   this.bindings = undefined;
+
+  // instance of ChainNode, inherited on demand via ChainNode.copy
   this.chains = undefined;
+
+  // instanceof ChainWatchers. Created on demand with a fresh new
+  // ChainWatchers at each level in prototype chain, by testing
+  // m.chainWatchers.obj.
   this.chainWatchers = undefined;
+
+  // plain inheritance, cloned at meta creation
   this.values = undefined;
+
+  // when meta(obj).proto === obj, the object is intended to be only a
+  // prototype and doesn't need to actually be observable itself
   this.proto = undefined;
 }
 

From 807b963ed318c4d6a7890a3aa0cf21e7525a99cf Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 17:31:29 -0400
Subject: [PATCH 05/39] encapsulated meta.cache

---
 packages/ember-metal/lib/chains.js            |  5 +-
 packages/ember-metal/lib/computed.js          | 30 ++++-----
 packages/ember-metal/lib/meta.js              | 64 +++++++++++++++++--
 .../ember-runtime/lib/system/core_object.js   |  2 +-
 4 files changed, 76 insertions(+), 25 deletions(-)

diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index 693de378a56..9884bc925ea 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -222,8 +222,9 @@ function lazyGet(obj, key) {
     return get(obj, key);
   // Otherwise attempt to get the cached value of the computed property
   } else {
-    if (meta.cache && key in meta.cache) {
-      return meta.cache[key];
+    let cache = meta.getCache();
+    if (cache && key in cache) {
+      return cache[key];
     }
   }
 }
diff --git a/packages/ember-metal/lib/computed.js b/packages/ember-metal/lib/computed.js
index d16a8b675ba..e205b9e4d34 100644
--- a/packages/ember-metal/lib/computed.js
+++ b/packages/ember-metal/lib/computed.js
@@ -266,9 +266,10 @@ ComputedPropertyPrototype.didChange = function(obj, keyName) {
   // _suspended is set via a CP.set to ensure we don't clear
   // the cached value set by the setter
   if (this._cacheable && this._suspended !== obj) {
-    var meta = metaFor(obj);
-    if (meta.cache && meta.cache[keyName] !== undefined) {
-      meta.cache[keyName] = undefined;
+    let meta = metaFor(obj);
+    let cache = meta.getCache();
+    if (cache && cache[keyName] !== undefined) {
+      cache[keyName] = undefined;
       removeDependentKeys(this, obj, keyName, meta);
     }
   }
@@ -305,9 +306,9 @@ ComputedPropertyPrototype.get = function(obj, keyName) {
   var ret, cache, meta;
   if (this._cacheable) {
     meta = metaFor(obj);
-    cache = meta.cache;
+    cache = meta.getOrCreateCache();
 
-    var result = cache && cache[keyName];
+    var result = cache[keyName];
 
     if (result === UNDEFINED) {
       return undefined;
@@ -316,10 +317,7 @@ ComputedPropertyPrototype.get = function(obj, keyName) {
     }
 
     ret = this._getter.call(obj, keyName);
-    cache = meta.cache;
-    if (!cache) {
-      cache = meta.cache = {};
-    }
+
     if (ret === undefined) {
       cache[keyName] = UNDEFINED;
     } else {
@@ -401,7 +399,7 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
   var cacheable      = this._cacheable;
   var setter         = this._setter;
   var meta           = metaFor(obj, cacheable);
-  var cache          = meta.cache;
+  var cache          = meta.getCache();
   var hadCachedValue = false;
 
   var cachedValue, ret;
@@ -441,7 +439,7 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
       addDependentKeys(this, obj, keyName, meta);
     }
     if (!cache) {
-      cache = meta.cache = {};
+      cache = meta.getOrCreateCache();
     }
     if (ret === undefined) {
       cache[keyName] = UNDEFINED;
@@ -460,13 +458,13 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
 /* called before property is overridden */
 ComputedPropertyPrototype.teardown = function(obj, keyName) {
   var meta = metaFor(obj);
-
-  if (meta.cache) {
-    if (keyName in meta.cache) {
+  let cache = meta.getCache();
+  if (cache) {
+    if (keyName in cache) {
       removeDependentKeys(this, obj, keyName, meta);
     }
 
-    if (this._cacheable) { delete meta.cache[keyName]; }
+    if (this._cacheable) { delete cache[keyName]; }
   }
 
   return null; // no value to restore
@@ -560,7 +558,7 @@ export default function computed(func) {
 */
 function cacheFor(obj, key) {
   var meta = obj['__ember_meta__'];
-  var cache = meta && meta.cache;
+  var cache = meta && meta.getCache();
   var ret = cache && cache[key];
 
   if (ret === UNDEFINED) {
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 3ca5f96ce94..604dcc3cc1f 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -9,14 +9,22 @@ import isEnabled from 'ember-metal/features';
 @module ember-metal
 */
 
-function Meta(obj) {
+let members = {
+  cache: ownMap
+};
+
+let memberNames = Object.keys(members);
+
+function Meta(obj, parentMeta) {
+  // preallocate a slot for each member
+  for (let i = 0; i < memberNames.length; i++) {
+    this['_' + memberNames[i]] = undefined;
+  }
+
   // map from strings to integer, with plain prototypical inheritance,
   // cloned at meta creation.
   this.watching = {};
 
-  // plain map with no inheritance
-  this.cache = undefined;
-
   // used only internally by meta() to distinguish meta-from-prototype
   // from instance's own meta
   this.source = obj;
@@ -51,6 +59,44 @@ function Meta(obj) {
   // when meta(obj).proto === obj, the object is intended to be only a
   // prototype and doesn't need to actually be observable itself
   this.proto = undefined;
+
+  // The next meta in our inheritance chain. We (will) track this
+  // explicitly instead of using prototypical inheritance because we
+  // have detailed knowledge of how each property should really be
+  // inherited, and we can optimize it much better than JS runtimes.
+  this.parent = parentMeta;
+}
+
+(function setupMembers() {
+  for (let i = 0; i < memberNames.length; i++) {
+    let name = memberNames[i];
+    let implementation = members[name];
+    implementation(name, Meta);
+  }
+})();
+
+
+// Implements a member that is a lazily created, non-inheritable
+// POJO. For member `thing` you get methods `getThing` and
+// `getOrCreateThing`.
+function ownMap(name, Meta) {
+  // This underscored name is preallocated in our constructor, so
+  // don't go changing it without updating that too.
+  let key = '_' + name;
+
+  let capitalized = name.replace(/^\w/, m => m.toUpperCase());
+
+  Meta.prototype['getOrCreate' + capitalized] = function() {
+    let ret = this[key];
+    if (!ret) {
+      ret = this[key] = Object.create(null);
+    }
+    return ret;
+  };
+
+  Meta.prototype['get' + capitalized] = function() {
+    return this[key];
+  };
 }
 
 export var META_DESC = {
@@ -109,9 +155,15 @@ export function meta(obj, writable) {
       ret.values = {};
     }
   } else if (ret.source !== obj) {
-    ret = Object.create(ret);
+    // temporary dance until I can eliminate remaining uses of
+    // prototype chain
+    let newRet = Object.create(ret);
+    newRet.parentMeta = ret;
+    ret = newRet;
+    ret._cache = undefined;
+    // end temporary dance
+
     ret.watching  = Object.create(ret.watching);
-    ret.cache     = undefined;
     ret.source    = obj;
 
     if (isEnabled('mandatory-setter')) {
diff --git a/packages/ember-runtime/lib/system/core_object.js b/packages/ember-runtime/lib/system/core_object.js
index 63bfc980dea..cdc63df5cc0 100644
--- a/packages/ember-runtime/lib/system/core_object.js
+++ b/packages/ember-runtime/lib/system/core_object.js
@@ -859,7 +859,7 @@ CoreObject.reopen({
   didDefineProperty(proto, key, value) {
     if (hasCachedComputedProperties === false) { return; }
     if (value instanceof Ember.ComputedProperty) {
-      var cache = Ember.meta(this.constructor).cache;
+      var cache = Ember.meta(this.constructor).getCache();
 
       if (cache && cache._computedProperties !== undefined) {
         cache._computedProperties = undefined;

From 31c16f0fffdb1caebd8ae86c5dd05db5ef1e58b2 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 17:33:01 -0400
Subject: [PATCH 06/39] generalize upgrade support

---
 packages/ember-metal/lib/meta.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 604dcc3cc1f..d1119abd08b 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -160,7 +160,10 @@ export function meta(obj, writable) {
     let newRet = Object.create(ret);
     newRet.parentMeta = ret;
     ret = newRet;
-    ret._cache = undefined;
+    for (let i = 0; i < memberNames.length; i++) {
+      let name = memberNames[i];
+      ret['_' + name] = undefined;
+    }
     // end temporary dance
 
     ret.watching  = Object.create(ret.watching);

From 4bb90091ec9544de26b64d857a9aa6feb860ce08 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:05:38 -0400
Subject: [PATCH 07/39] more progress on generic meta accessors

---
 packages/ember-metal/lib/meta.js | 53 ++++++++++++++++++++++++++------
 1 file changed, 44 insertions(+), 9 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index d1119abd08b..bf897d83e8c 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -18,7 +18,7 @@ let memberNames = Object.keys(members);
 function Meta(obj, parentMeta) {
   // preallocate a slot for each member
   for (let i = 0; i < memberNames.length; i++) {
-    this['_' + memberNames[i]] = undefined;
+    this[memberProperty(memberNames[i])] = undefined;
   }
 
   // map from strings to integer, with plain prototypical inheritance,
@@ -80,11 +80,8 @@ function Meta(obj, parentMeta) {
 // POJO. For member `thing` you get methods `getThing` and
 // `getOrCreateThing`.
 function ownMap(name, Meta) {
-  // This underscored name is preallocated in our constructor, so
-  // don't go changing it without updating that too.
-  let key = '_' + name;
-
-  let capitalized = name.replace(/^\w/, m => m.toUpperCase());
+  let key = memberProperty(name);
+  let capitalized = capitalize(name);
 
   Meta.prototype['getOrCreate' + capitalized] = function() {
     let ret = this[key];
@@ -99,6 +96,45 @@ function ownMap(name, Meta) {
   };
 }
 
+// Implements a member that is lazily created POJO with inheritable
+// values. For member `thing` you get methods `getThing`,
+// `getOrCreateThing`, and `peekThing`.
+function inheritedMap(name, Meta) {
+  let key = memberProperty(name);
+  let capitalized = capitalize(name);
+
+  let getOrCreate = Meta.prototype['getOrCreate' + capitalized] = function() {
+    let ret = this[key];
+    if (!ret) {
+      if (this.parent && this.parent[key]) {
+        ret = this[key] = Object.create(this.parent[key]);
+      } else {
+        ret = this[key] = Object.create(null);
+      }
+    }
+    return ret;
+  };
+
+  Meta.prototype['get' + capitalized] = getOrCreate;
+
+  Meta.prototype['peek' + capitalized] = function(subkey) {
+    let map = getOrCreate.apply(this);
+    if (map) {
+      return map[subkey];
+    }
+  };
+}
+
+function memberProperty(name) {
+  return '_' + name;
+}
+
+// there's a more general-purpose capitalize in ember-runtime, but we
+// don't want to make ember-metal depend on ember-runtime.
+function capitalize(name) {
+  return name.replace(/^\w/, m => m.toUpperCase());
+}
+
 export var META_DESC = {
   writable: true,
   configurable: true,
@@ -158,11 +194,10 @@ export function meta(obj, writable) {
     // temporary dance until I can eliminate remaining uses of
     // prototype chain
     let newRet = Object.create(ret);
-    newRet.parentMeta = ret;
+    newRet.parent = ret;
     ret = newRet;
     for (let i = 0; i < memberNames.length; i++) {
-      let name = memberNames[i];
-      ret['_' + name] = undefined;
+      ret[memberProperty(memberNames[i])] = undefined;
     }
     // end temporary dance
 

From d885f23999d1d2f45079dcd7860b77d8674f0d27 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:21:16 -0400
Subject: [PATCH 08/39] encapsulated meta.watching

---
 packages/ember-metal/lib/alias.js             |  4 ++--
 packages/ember-metal/lib/computed.js          |  2 +-
 packages/ember-metal/lib/meta.js              | 19 ++++++++-----------
 packages/ember-metal/lib/properties.js        |  2 +-
 packages/ember-metal/lib/property_events.js   |  4 ++--
 packages/ember-metal/lib/property_get.js      |  2 +-
 packages/ember-metal/lib/property_set.js      |  2 +-
 packages/ember-metal/lib/watch_key.js         |  8 ++++----
 packages/ember-metal/lib/watch_path.js        |  8 ++++----
 packages/ember-metal/lib/watching.js          |  2 +-
 .../ember-metal/tests/watching/watch_test.js  |  8 ++++----
 .../ember/tests/routing/query_params_test.js  |  6 ++----
 12 files changed, 31 insertions(+), 36 deletions(-)

diff --git a/packages/ember-metal/lib/alias.js b/packages/ember-metal/lib/alias.js
index 77b77ffa2e2..29e4240260e 100644
--- a/packages/ember-metal/lib/alias.js
+++ b/packages/ember-metal/lib/alias.js
@@ -47,14 +47,14 @@ AliasedProperty.prototype.didUnwatch = function(obj, keyName) {
 AliasedProperty.prototype.setup = function(obj, keyName) {
   Ember.assert(`Setting alias '${keyName}' on self`, this.altKey !== keyName);
   var m = meta(obj);
-  if (m.watching[keyName]) {
+  if (m.peekWatching(keyName)) {
     addDependentKeys(this, obj, keyName, m);
   }
 };
 
 AliasedProperty.prototype.teardown = function(obj, keyName) {
   var m = meta(obj);
-  if (m.watching[keyName]) {
+  if (m.peekWatching(keyName)) {
     removeDependentKeys(this, obj, keyName, m);
   }
 };
diff --git a/packages/ember-metal/lib/computed.js b/packages/ember-metal/lib/computed.js
index e205b9e4d34..2ba3892f01e 100644
--- a/packages/ember-metal/lib/computed.js
+++ b/packages/ember-metal/lib/computed.js
@@ -425,7 +425,7 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
 
   if (hadCachedValue && cachedValue === ret) { return; }
 
-  var watched = meta.watching[keyName];
+  var watched = meta.peekWatching(keyName);
   if (watched) {
     propertyWillChange(obj, keyName);
   }
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index bf897d83e8c..2240255aed2 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -10,7 +10,8 @@ import isEnabled from 'ember-metal/features';
 */
 
 let members = {
-  cache: ownMap
+  cache: ownMap,
+  watching: inheritedMap
 };
 
 let memberNames = Object.keys(members);
@@ -21,10 +22,6 @@ function Meta(obj, parentMeta) {
     this[memberProperty(memberNames[i])] = undefined;
   }
 
-  // map from strings to integer, with plain prototypical inheritance,
-  // cloned at meta creation.
-  this.watching = {};
-
   // used only internally by meta() to distinguish meta-from-prototype
   // from instance's own meta
   this.source = obj;
@@ -106,8 +103,8 @@ function inheritedMap(name, Meta) {
   let getOrCreate = Meta.prototype['getOrCreate' + capitalized] = function() {
     let ret = this[key];
     if (!ret) {
-      if (this.parent && this.parent[key]) {
-        ret = this[key] = Object.create(this.parent[key]);
+      if (this.parent) {
+        ret = this[key] = Object.create(getOrCreate.apply(this.parent));
       } else {
         ret = this[key] = Object.create(null);
       }
@@ -186,7 +183,7 @@ export function meta(obj, writable) {
 
   if (!ret) {
     ret = new Meta(obj);
-
+    //ret._watching = {}; //fixme
     if (isEnabled('mandatory-setter')) {
       ret.values = {};
     }
@@ -195,13 +192,13 @@ export function meta(obj, writable) {
     // prototype chain
     let newRet = Object.create(ret);
     newRet.parent = ret;
-    ret = newRet;
     for (let i = 0; i < memberNames.length; i++) {
-      ret[memberProperty(memberNames[i])] = undefined;
+      newRet[memberProperty(memberNames[i])] = undefined;
     }
+    //newRet._watching = Object.create(ret._watching); // fixme
+    ret = newRet;
     // end temporary dance
 
-    ret.watching  = Object.create(ret.watching);
     ret.source    = obj;
 
     if (isEnabled('mandatory-setter')) {
diff --git a/packages/ember-metal/lib/properties.js b/packages/ember-metal/lib/properties.js
index d5f7600ae11..2094b10dfbe 100644
--- a/packages/ember-metal/lib/properties.js
+++ b/packages/ember-metal/lib/properties.js
@@ -89,7 +89,7 @@ export function defineProperty(obj, keyName, desc, data, meta) {
   if (!meta) {
     meta = metaFor(obj);
   }
-  var watchEntry = meta.watching[keyName];
+  var watchEntry = meta.peekWatching(keyName);
   possibleDesc = obj[keyName];
   existingDesc = (possibleDesc !== null && typeof possibleDesc === 'object' && possibleDesc.isDescriptor) ? possibleDesc : undefined;
 
diff --git a/packages/ember-metal/lib/property_events.js b/packages/ember-metal/lib/property_events.js
index f46505f4f50..2a259bd0b74 100644
--- a/packages/ember-metal/lib/property_events.js
+++ b/packages/ember-metal/lib/property_events.js
@@ -36,7 +36,7 @@ var deferred = 0;
 */
 function propertyWillChange(obj, keyName) {
   var m = obj['__ember_meta__'];
-  var watching = (m && m.watching[keyName] > 0) || keyName === 'length';
+  var watching = (m && m.peekWatching(keyName) > 0) || keyName === 'length';
   var proto = m && m.proto;
   var possibleDesc = obj[keyName];
   var desc = (possibleDesc !== null && typeof possibleDesc === 'object' && possibleDesc.isDescriptor) ? possibleDesc : undefined;
@@ -76,7 +76,7 @@ function propertyWillChange(obj, keyName) {
 */
 function propertyDidChange(obj, keyName) {
   var m = obj['__ember_meta__'];
-  var watching = (m && m.watching[keyName] > 0) || keyName === 'length';
+  var watching = (m && m.peekWatching(keyName) > 0) || keyName === 'length';
   var proto = m && m.proto;
   var possibleDesc = obj[keyName];
   var desc = (possibleDesc !== null && typeof possibleDesc === 'object' && possibleDesc.isDescriptor) ? possibleDesc : undefined;
diff --git a/packages/ember-metal/lib/property_get.js b/packages/ember-metal/lib/property_get.js
index a96fdcc7892..814288f7101 100644
--- a/packages/ember-metal/lib/property_get.js
+++ b/packages/ember-metal/lib/property_get.js
@@ -69,7 +69,7 @@ export function get(obj, keyName) {
     return desc.get(obj, keyName);
   } else {
     if (isEnabled('mandatory-setter')) {
-      if (meta && meta.watching[keyName] > 0) {
+      if (meta && meta.peekWatching(keyName) > 0) {
         ret = meta.values[keyName];
       } else {
         ret = obj[keyName];
diff --git a/packages/ember-metal/lib/property_set.js b/packages/ember-metal/lib/property_set.js
index 7275e4ec106..37c3d7bce13 100644
--- a/packages/ember-metal/lib/property_set.js
+++ b/packages/ember-metal/lib/property_set.js
@@ -63,7 +63,7 @@ export function set(obj, keyName, value, tolerant) {
     // `setUnknownProperty` method exists on the object
     if (isUnknown && 'function' === typeof obj.setUnknownProperty) {
       obj.setUnknownProperty(keyName, value);
-    } else if (meta && meta.watching[keyName] > 0) {
+    } else if (meta && meta.peekWatching(keyName) > 0) {
       if (meta.proto !== obj) {
         if (isEnabled('mandatory-setter')) {
           currentValue = meta.values[keyName];
diff --git a/packages/ember-metal/lib/watch_key.js b/packages/ember-metal/lib/watch_key.js
index 473b49989a8..3d920295cac 100644
--- a/packages/ember-metal/lib/watch_key.js
+++ b/packages/ember-metal/lib/watch_key.js
@@ -12,7 +12,7 @@ export function watchKey(obj, keyName, meta) {
   if (keyName === 'length' && Array.isArray(obj)) { return; }
 
   var m = meta || metaFor(obj);
-  var watching = m.watching;
+  var watching = m.getOrCreateWatching();
 
   // activate watching first time
   if (!watching[keyName]) {
@@ -65,9 +65,9 @@ if (isEnabled('mandatory-setter')) {
 
 export function unwatchKey(obj, keyName, meta) {
   var m = meta || metaFor(obj);
-  var watching = m.watching;
+  var watching = m.getWatching();
 
-  if (watching[keyName] === 1) {
+  if (watching && watching[keyName] === 1) {
     watching[keyName] = 0;
 
     var possibleDesc = obj[keyName];
@@ -97,7 +97,7 @@ export function unwatchKey(obj, keyName, meta) {
         });
       }
     }
-  } else if (watching[keyName] > 1) {
+  } else if (watching && watching[keyName] > 1) {
     watching[keyName]--;
   }
 }
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index a5d67dc4f10..0244ee03b09 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -22,7 +22,7 @@ export function watchPath(obj, keyPath, meta) {
   if (keyPath === 'length' && Array.isArray(obj)) { return; }
 
   var m = meta || metaFor(obj);
-  var watching = m.watching;
+  var watching = m.getOrCreateWatching();
 
   if (!watching[keyPath]) { // activate watching first time
     watching[keyPath] = 1;
@@ -34,12 +34,12 @@ export function watchPath(obj, keyPath, meta) {
 
 export function unwatchPath(obj, keyPath, meta) {
   var m = meta || metaFor(obj);
-  var watching = m.watching;
+  var watching = m.getWatching();
 
-  if (watching[keyPath] === 1) {
+  if (watching && watching[keyPath] === 1) {
     watching[keyPath] = 0;
     chainsFor(obj, m).remove(keyPath);
-  } else if (watching[keyPath] > 1) {
+  } else if (watching && watching[keyPath] > 1) {
     watching[keyPath]--;
   }
 }
diff --git a/packages/ember-metal/lib/watching.js b/packages/ember-metal/lib/watching.js
index ed21b727245..74c247d8033 100644
--- a/packages/ember-metal/lib/watching.js
+++ b/packages/ember-metal/lib/watching.js
@@ -46,7 +46,7 @@ export { watch };
 
 export function isWatching(obj, key) {
   var meta = obj['__ember_meta__'];
-  return (meta && meta.watching[key]) > 0;
+  return (meta && meta.peekWatching(key)) > 0;
 }
 
 watch.flushPending = flushPendingChains;
diff --git a/packages/ember-metal/tests/watching/watch_test.js b/packages/ember-metal/tests/watching/watch_test.js
index 910a9d8e9c6..e4a6121d72b 100644
--- a/packages/ember-metal/tests/watching/watch_test.js
+++ b/packages/ember-metal/tests/watching/watch_test.js
@@ -205,12 +205,12 @@ QUnit.test('when watching a global object, destroy should remove chain watchers
   var meta_Global = Ember.meta(Global);
   var chainNode = Ember.meta(obj).chains._chains.Global._chains.foo;
 
-  equal(meta_Global.watching.foo, 1, 'should be watching foo');
+  equal(meta_Global.peekWatching('foo'), 1, 'should be watching foo');
   equal(meta_Global.chainWatchers.has('foo', chainNode), true, 'should have chain watcher');
 
   destroy(obj);
 
-  equal(meta_Global.watching.foo, 0, 'should not be watching foo');
+  equal(meta_Global.peekWatching('foo'), 0, 'should not be watching foo');
   equal(meta_Global.chainWatchers.has('foo', chainNode), false, 'should not have chain watcher');
 
   lookup['Global'] = Global = null; // reset
@@ -227,12 +227,12 @@ QUnit.test('when watching another object, destroy should remove chain watchers f
   var meta_objB = Ember.meta(objB);
   var chainNode = Ember.meta(objA).chains._chains.b._chains.foo;
 
-  equal(meta_objB.watching.foo, 1, 'should be watching foo');
+  equal(meta_objB.peekWatching('foo'), 1, 'should be watching foo');
   equal(meta_objB.chainWatchers.has('foo', chainNode), true, 'should have chain watcher');
 
   destroy(objA);
 
-  equal(meta_objB.watching.foo, 0, 'should not be watching foo');
+  equal(meta_objB.peekWatching('foo'), 0, 'should not be watching foo');
   equal(meta_objB.chainWatchers.has('foo', chainNode), false, 'should not have chain watcher');
 });
 
diff --git a/packages/ember/tests/routing/query_params_test.js b/packages/ember/tests/routing/query_params_test.js
index ce42493a938..02508274021 100644
--- a/packages/ember/tests/routing/query_params_test.js
+++ b/packages/ember/tests/routing/query_params_test.js
@@ -1811,7 +1811,7 @@ if (isEnabled('ember-routing-route-configured-query-params')) {
     App.OtherRoute = Ember.Route.extend({
       model(p, trans) {
         var m = Ember.meta(trans.params.application);
-        ok(!m.watching.woot, 'A meta object isn\'t constructed for this params POJO');
+        ok(!m.peekWatching('woot'), 'A meta object isn\'t constructed for this params POJO');
       }
     });
 
@@ -2960,7 +2960,7 @@ if (isEnabled('ember-routing-route-configured-query-params')) {
     App.OtherRoute = Ember.Route.extend({
       model(p, trans) {
         var m = Ember.meta(trans.params.application);
-        ok(!m.watching.woot, 'A meta object isn\'t constructed for this params POJO');
+        ok(!m.peekWatching('woot'), 'A meta object isn\'t constructed for this params POJO');
       }
     });
 
@@ -3102,5 +3102,3 @@ QUnit.test('handle routes names that clash with Object.prototype properties', fu
   var controller = container.lookup('controller:constructor');
   equal(get(controller, 'foo'), '999');
 });
-
-

From 542765bf69b4c47c5c48abd0251e50fb65098a0c Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:24:25 -0400
Subject: [PATCH 09/39] align semantics

---
 packages/ember-metal/lib/meta.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 2240255aed2..a603e08f02b 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -112,10 +112,10 @@ function inheritedMap(name, Meta) {
     return ret;
   };
 
-  Meta.prototype['get' + capitalized] = getOrCreate;
+  let getId = Meta.prototype['get' + capitalized] = getOrCreate;
 
   Meta.prototype['peek' + capitalized] = function(subkey) {
-    let map = getOrCreate.apply(this);
+    let map = getId.apply(this);
     if (map) {
       return map[subkey];
     }

From a4c9dd32a286da6a12b1ced163d65206877cca23 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:29:04 -0400
Subject: [PATCH 10/39] lazy watchers

---
 packages/ember-metal/lib/meta.js       | 10 +++++++++-
 packages/ember-metal/lib/watch_key.js  |  6 +++---
 packages/ember-metal/lib/watch_path.js |  6 +++---
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index a603e08f02b..76fc31fabdf 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -112,7 +112,15 @@ function inheritedMap(name, Meta) {
     return ret;
   };
 
-  let getId = Meta.prototype['get' + capitalized] = getOrCreate;
+  let getId = Meta.prototype['get' + capitalized] = function() {
+    let pointer = this;
+    while (pointer) {
+      if (pointer[key]) {
+        return pointer[key];
+      }
+      pointer = pointer.parent;
+    }
+  };
 
   Meta.prototype['peek' + capitalized] = function(subkey) {
     let map = getId.apply(this);
diff --git a/packages/ember-metal/lib/watch_key.js b/packages/ember-metal/lib/watch_key.js
index 3d920295cac..0b9e1310c08 100644
--- a/packages/ember-metal/lib/watch_key.js
+++ b/packages/ember-metal/lib/watch_key.js
@@ -65,9 +65,9 @@ if (isEnabled('mandatory-setter')) {
 
 export function unwatchKey(obj, keyName, meta) {
   var m = meta || metaFor(obj);
-  var watching = m.getWatching();
+  var watching = m.getOrCreateWatching();
 
-  if (watching && watching[keyName] === 1) {
+  if (watching[keyName] === 1) {
     watching[keyName] = 0;
 
     var possibleDesc = obj[keyName];
@@ -97,7 +97,7 @@ export function unwatchKey(obj, keyName, meta) {
         });
       }
     }
-  } else if (watching && watching[keyName] > 1) {
+  } else if (watching[keyName] > 1) {
     watching[keyName]--;
   }
 }
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index 0244ee03b09..c40194b5af5 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -34,12 +34,12 @@ export function watchPath(obj, keyPath, meta) {
 
 export function unwatchPath(obj, keyPath, meta) {
   var m = meta || metaFor(obj);
-  var watching = m.getWatching();
+  var watching = m.getOrCreateWatching();
 
-  if (watching && watching[keyPath] === 1) {
+  if (watching[keyPath] === 1) {
     watching[keyPath] = 0;
     chainsFor(obj, m).remove(keyPath);
-  } else if (watching && watching[keyPath] > 1) {
+  } else if (watching[keyPath] > 1) {
     watching[keyPath]--;
   }
 }

From 68895eca32a33f2d52011b932e07ae09f7af6670 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:36:05 -0400
Subject: [PATCH 11/39] encapsulated meta.mixins

---
 packages/ember-metal/lib/meta.js  |  6 ++----
 packages/ember-metal/lib/mixin.js | 20 +++++---------------
 2 files changed, 7 insertions(+), 19 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 76fc31fabdf..31d02d4f5c8 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -11,7 +11,8 @@ import isEnabled from 'ember-metal/features';
 
 let members = {
   cache: ownMap,
-  watching: inheritedMap
+  watching: inheritedMap,
+  mixins: inheritedMap
 };
 
 let memberNames = Object.keys(members);
@@ -35,9 +36,6 @@ function Meta(obj, parentMeta) {
   // demand with o_create.
   this.listeners = undefined;
 
-  // o_create inherited on demand
-  this.mixins = undefined;
-
   // o_create inherited on demand. May also get wiped out with a
   // direct `m.bindings = {}` after they're handled.
   this.bindings = undefined;
diff --git a/packages/ember-metal/lib/mixin.js b/packages/ember-metal/lib/mixin.js
index b7807b25cf7..494098d3d3a 100644
--- a/packages/ember-metal/lib/mixin.js
+++ b/packages/ember-metal/lib/mixin.js
@@ -74,14 +74,7 @@ superFunction.call(primer, 1, 2);
 superFunction.call(primer, 1, 2, 3);
 
 function mixinsMeta(obj) {
-  var m = metaFor(obj, true);
-  var ret = m.mixins;
-  if (!ret) {
-    ret = m.mixins = {};
-  } else if (!m.hasOwnProperty('mixins')) {
-    ret = m.mixins = Object.create(ret);
-  }
-  return ret;
+  return metaFor(obj, true).getOrCreateMixins();
 }
 
 function isMethod(obj) {
@@ -667,12 +660,9 @@ function _detect(curMixin, targetMixin, seen) {
 MixinPrototype.detect = function(obj) {
   if (!obj) { return false; }
   if (obj instanceof Mixin) { return _detect(obj, this, {}); }
-  var m = obj['__ember_meta__'];
-  var mixins = m && m.mixins;
-  if (mixins) {
-    return !!mixins[guidFor(this)];
-  }
-  return false;
+  var m = obj.__ember_meta__;
+  if (!m) { return false; }
+  return !!m.peekMixins(guidFor(this));
 };
 
 MixinPrototype.without = function(...args) {
@@ -712,7 +702,7 @@ MixinPrototype.keys = function() {
 // TODO: Make Ember.mixin
 Mixin.mixins = function(obj) {
   var m = obj['__ember_meta__'];
-  var mixins = m && m.mixins;
+  var mixins = m && m.getMixins();
   var ret = [];
 
   if (!mixins) { return ret; }

From aab8f9a23aca8ea74467cdadeb60b5378ef7dfd1 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:41:47 -0400
Subject: [PATCH 12/39] encapsulate meta.bindings

---
 packages/ember-metal/lib/meta.js                 | 13 ++++++-------
 packages/ember-metal/lib/mixin.js                | 12 +++---------
 packages/ember-runtime/lib/system/core_object.js |  8 +-------
 3 files changed, 10 insertions(+), 23 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 31d02d4f5c8..3f3a6317689 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -12,7 +12,8 @@ import isEnabled from 'ember-metal/features';
 let members = {
   cache: ownMap,
   watching: inheritedMap,
-  mixins: inheritedMap
+  mixins: inheritedMap,
+  bindings: inheritedMap
 };
 
 let memberNames = Object.keys(members);
@@ -36,10 +37,6 @@ function Meta(obj, parentMeta) {
   // demand with o_create.
   this.listeners = undefined;
 
-  // o_create inherited on demand. May also get wiped out with a
-  // direct `m.bindings = {}` after they're handled.
-  this.bindings = undefined;
-
   // instance of ChainNode, inherited on demand via ChainNode.copy
   this.chains = undefined;
 
@@ -126,6 +123,10 @@ function inheritedMap(name, Meta) {
       return map[subkey];
     }
   };
+
+  Meta.prototype['clear' + capitalized] = function() {
+    this[key] = Object.create(null);
+  };
 }
 
 function memberProperty(name) {
@@ -189,7 +190,6 @@ export function meta(obj, writable) {
 
   if (!ret) {
     ret = new Meta(obj);
-    //ret._watching = {}; //fixme
     if (isEnabled('mandatory-setter')) {
       ret.values = {};
     }
@@ -201,7 +201,6 @@ export function meta(obj, writable) {
     for (let i = 0; i < memberNames.length; i++) {
       newRet[memberProperty(memberNames[i])] = undefined;
     }
-    //newRet._watching = Object.create(ret._watching); // fixme
     ret = newRet;
     // end temporary dance
 
diff --git a/packages/ember-metal/lib/mixin.js b/packages/ember-metal/lib/mixin.js
index 494098d3d3a..3aba637b6f2 100644
--- a/packages/ember-metal/lib/mixin.js
+++ b/packages/ember-metal/lib/mixin.js
@@ -309,13 +309,7 @@ var IS_BINDING = /^.+Binding$/;
 
 function detectBinding(obj, key, value, m) {
   if (IS_BINDING.test(key)) {
-    var bindings = m.bindings;
-    if (!bindings) {
-      bindings = m.bindings = {};
-    } else if (!m.hasOwnProperty('bindings')) {
-      bindings = m.bindings = Object.create(m.bindings);
-    }
-    bindings[key] = value;
+    m.getOrCreateBindings()[key] = value;
   }
 }
 
@@ -346,7 +340,7 @@ function connectStreamBinding(obj, key, stream) {
 
 function connectBindings(obj, m) {
   // TODO Mixin.apply(instance) should disconnect binding if exists
-  var bindings = m.bindings;
+  var bindings = m.getBindings();
   var key, binding, to;
   if (bindings) {
     for (key in bindings) {
@@ -367,7 +361,7 @@ function connectBindings(obj, m) {
       }
     }
     // mark as applied
-    m.bindings = {};
+    m.clearBindings();
   }
 }
 
diff --git a/packages/ember-runtime/lib/system/core_object.js b/packages/ember-runtime/lib/system/core_object.js
index cdc63df5cc0..d2a8fef8168 100644
--- a/packages/ember-runtime/lib/system/core_object.js
+++ b/packages/ember-runtime/lib/system/core_object.js
@@ -104,13 +104,7 @@ function makeCtor() {
           var value = properties[keyName];
 
           if (IS_BINDING.test(keyName)) {
-            var bindings = m.bindings;
-            if (!bindings) {
-              bindings = m.bindings = {};
-            } else if (!m.hasOwnProperty('bindings')) {
-              bindings = m.bindings = Object.create(m.bindings);
-            }
-            bindings[keyName] = value;
+            m.getOrCreateBindings()[keyName] = value;
           }
 
           var possibleDesc = this[keyName];

From 0b96990950245f229f5ba68417430b3ea1863b7f Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 18:49:29 -0400
Subject: [PATCH 13/39] encapsulated meta.values

---
 packages/ember-metal/lib/meta.js                   | 14 ++++----------
 packages/ember-metal/lib/properties.js             |  4 ++--
 packages/ember-metal/lib/property_get.js           |  2 +-
 packages/ember-metal/lib/property_set.js           |  4 ++--
 packages/ember-metal/lib/watch_key.js              |  4 ++--
 .../tests/accessors/mandatory_setters_test.js      |  8 ++++----
 6 files changed, 15 insertions(+), 21 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 3f3a6317689..eeb14f09505 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -13,7 +13,8 @@ let members = {
   cache: ownMap,
   watching: inheritedMap,
   mixins: inheritedMap,
-  bindings: inheritedMap
+  bindings: inheritedMap,
+  values: inheritedMap
 };
 
 let memberNames = Object.keys(members);
@@ -45,9 +46,6 @@ function Meta(obj, parentMeta) {
   // m.chainWatchers.obj.
   this.chainWatchers = undefined;
 
-  // plain inheritance, cloned at meta creation
-  this.values = undefined;
-
   // when meta(obj).proto === obj, the object is intended to be only a
   // prototype and doesn't need to actually be observable itself
   this.proto = undefined;
@@ -155,7 +153,7 @@ var EMBER_META_PROPERTY = {
 export var EMPTY_META = new Meta(null);
 
 if (isEnabled('mandatory-setter')) {
-  EMPTY_META.values = {};
+  EMPTY_META.getOrCreateValues();
 }
 
 /**
@@ -191,7 +189,7 @@ export function meta(obj, writable) {
   if (!ret) {
     ret = new Meta(obj);
     if (isEnabled('mandatory-setter')) {
-      ret.values = {};
+      ret.getOrCreateValues();
     }
   } else if (ret.source !== obj) {
     // temporary dance until I can eliminate remaining uses of
@@ -205,10 +203,6 @@ export function meta(obj, writable) {
     // end temporary dance
 
     ret.source    = obj;
-
-    if (isEnabled('mandatory-setter')) {
-      ret.values = Object.create(ret.values);
-    }
   }
   obj.__ember_meta__ = ret;
   return ret;
diff --git a/packages/ember-metal/lib/properties.js b/packages/ember-metal/lib/properties.js
index 2094b10dfbe..abb25b1f0cf 100644
--- a/packages/ember-metal/lib/properties.js
+++ b/packages/ember-metal/lib/properties.js
@@ -34,7 +34,7 @@ export function MANDATORY_SETTER_FUNCTION(name) {
 export function DEFAULT_GETTER_FUNCTION(name) {
   return function GETTER_FUNCTION() {
     var meta = this['__ember_meta__'];
-    return meta && meta.values[name];
+    return meta && meta.peekValues(name);
   };
 }
 
@@ -122,7 +122,7 @@ export function defineProperty(obj, keyName, desc, data, meta) {
 
       if (isEnabled('mandatory-setter')) {
         if (watching) {
-          meta.values[keyName] = data;
+          meta.getOrCreateValues()[keyName] = data;
           Object.defineProperty(obj, keyName, {
             configurable: true,
             enumerable: true,
diff --git a/packages/ember-metal/lib/property_get.js b/packages/ember-metal/lib/property_get.js
index 814288f7101..26533b0f17a 100644
--- a/packages/ember-metal/lib/property_get.js
+++ b/packages/ember-metal/lib/property_get.js
@@ -70,7 +70,7 @@ export function get(obj, keyName) {
   } else {
     if (isEnabled('mandatory-setter')) {
       if (meta && meta.peekWatching(keyName) > 0) {
-        ret = meta.values[keyName];
+        ret = meta.peekValues(keyName);
       } else {
         ret = obj[keyName];
       }
diff --git a/packages/ember-metal/lib/property_set.js b/packages/ember-metal/lib/property_set.js
index 37c3d7bce13..2ebbafebd2c 100644
--- a/packages/ember-metal/lib/property_set.js
+++ b/packages/ember-metal/lib/property_set.js
@@ -66,7 +66,7 @@ export function set(obj, keyName, value, tolerant) {
     } else if (meta && meta.peekWatching(keyName) > 0) {
       if (meta.proto !== obj) {
         if (isEnabled('mandatory-setter')) {
-          currentValue = meta.values[keyName];
+          currentValue = meta.peekValues(keyName);
         } else {
           currentValue = obj[keyName];
         }
@@ -81,7 +81,7 @@ export function set(obj, keyName, value, tolerant) {
           ) {
             defineProperty(obj, keyName, null, value); // setup mandatory setter
           } else {
-            meta.values[keyName] = value;
+            meta.getOrCreateValues()[keyName] = value;
           }
         } else {
           obj[keyName] = value;
diff --git a/packages/ember-metal/lib/watch_key.js b/packages/ember-metal/lib/watch_key.js
index 0b9e1310c08..873b82cd519 100644
--- a/packages/ember-metal/lib/watch_key.js
+++ b/packages/ember-metal/lib/watch_key.js
@@ -48,7 +48,7 @@ if (isEnabled('mandatory-setter')) {
 
     // this x in Y deopts, so keeping it in this function is better;
     if (configurable && isWritable && hasValue && keyName in obj) {
-      m.values[keyName] = obj[keyName];
+      m.getOrCreateValues()[keyName] = obj[keyName];
       Object.defineProperty(obj, keyName, {
         configurable: true,
         enumerable: Object.prototype.propertyIsEnumerable.call(obj, keyName),
@@ -91,7 +91,7 @@ export function unwatchKey(obj, keyName, meta) {
               enumerable: true,
               value: val
             });
-            delete m.values[keyName];
+            delete m.getOrCreateValues()[keyName];
           },
           get: DEFAULT_GETTER_FUNCTION(keyName)
         });
diff --git a/packages/ember-metal/tests/accessors/mandatory_setters_test.js b/packages/ember-metal/tests/accessors/mandatory_setters_test.js
index 993cbf4372d..21df14d4058 100644
--- a/packages/ember-metal/tests/accessors/mandatory_setters_test.js
+++ b/packages/ember-metal/tests/accessors/mandatory_setters_test.js
@@ -8,8 +8,8 @@ QUnit.module('mandatory-setters');
 
 function hasMandatorySetter(object, property) {
   var meta = metaFor(object);
-
-  return property in meta.values;
+  let values = meta.getValues();
+  return values && property in values;
 }
 
 if (isEnabled('mandatory-setter')) {
@@ -114,7 +114,7 @@ if (isEnabled('mandatory-setter')) {
     });
 
     watch(obj, 'someProp');
-    ok(!('someProp' in meta.values), 'blastix');
+    ok(!('someProp' in meta.getValues()), 'blastix');
   });
 
   QUnit.test('sets up mandatory-setter if property comes from prototype', function() {
@@ -131,7 +131,7 @@ if (isEnabled('mandatory-setter')) {
     watch(obj2, 'someProp');
     var meta = metaFor(obj2);
 
-    ok(('someProp' in meta.values), 'mandatory setter has been setup');
+    ok(('someProp' in meta.getValues()), 'mandatory setter has been setup');
 
     expectAssertion(function() {
       obj2.someProp = 'foo-bar';

From bbfb0e701973587dd0f89518cd5d5fffeb0b3f34 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 19:04:01 -0400
Subject: [PATCH 14/39] typos

---
 packages/ember-metal/lib/meta.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index eeb14f09505..4a0bd2480b5 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -86,7 +86,7 @@ function ownMap(name, Meta) {
   };
 }
 
-// Implements a member that is lazily created POJO with inheritable
+// Implements a member that is a lazily created POJO with inheritable
 // values. For member `thing` you get methods `getThing`,
 // `getOrCreateThing`, and `peekThing`.
 function inheritedMap(name, Meta) {
@@ -105,7 +105,7 @@ function inheritedMap(name, Meta) {
     return ret;
   };
 
-  let getId = Meta.prototype['get' + capitalized] = function() {
+  let getIt = Meta.prototype['get' + capitalized] = function() {
     let pointer = this;
     while (pointer) {
       if (pointer[key]) {
@@ -116,7 +116,7 @@ function inheritedMap(name, Meta) {
   };
 
   Meta.prototype['peek' + capitalized] = function(subkey) {
-    let map = getId.apply(this);
+    let map = getIt.apply(this);
     if (map) {
       return map[subkey];
     }

From c40512a349b56cce234e071f5365f51a8f4193ec Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 19:18:41 -0400
Subject: [PATCH 15/39] extra reusable bits

---
 packages/ember-metal/lib/meta.js | 64 ++++++++++++++++++--------------
 1 file changed, 36 insertions(+), 28 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 4a0bd2480b5..67160a0d593 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -72,18 +72,18 @@ function Meta(obj, parentMeta) {
 function ownMap(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
-
   Meta.prototype['getOrCreate' + capitalized] = function() {
-    let ret = this[key];
-    if (!ret) {
-      ret = this[key] = Object.create(null);
-    }
-    return ret;
+    return getOrCreateOwnMap.call(this, key);
   };
+  Meta.prototype['get' + capitalized] = function() { return this[key]; };
+}
 
-  Meta.prototype['get' + capitalized] = function() {
-    return this[key];
-  };
+function getOrCreateOwnMap(key) {
+  let ret = this[key];
+  if (!ret) {
+    ret = this[key] = Object.create(null);
+  }
+  return ret;
 }
 
 // Implements a member that is a lazily created POJO with inheritable
@@ -93,30 +93,16 @@ function inheritedMap(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
 
-  let getOrCreate = Meta.prototype['getOrCreate' + capitalized] = function() {
-    let ret = this[key];
-    if (!ret) {
-      if (this.parent) {
-        ret = this[key] = Object.create(getOrCreate.apply(this.parent));
-      } else {
-        ret = this[key] = Object.create(null);
-      }
-    }
-    return ret;
+  Meta.prototype['getOrCreate' + capitalized] = function() {
+    return getOrCreateInheritedMap.call(this, key);
   };
 
-  let getIt = Meta.prototype['get' + capitalized] = function() {
-    let pointer = this;
-    while (pointer) {
-      if (pointer[key]) {
-        return pointer[key];
-      }
-      pointer = pointer.parent;
-    }
+  Meta.prototype['get' + capitalized] = function() {
+    return getInheritedMap.call(this, key);
   };
 
   Meta.prototype['peek' + capitalized] = function(subkey) {
-    let map = getIt.apply(this);
+    let map = getInheritedMap.call(this, key);
     if (map) {
       return map[subkey];
     }
@@ -127,6 +113,28 @@ function inheritedMap(name, Meta) {
   };
 }
 
+function getOrCreateInheritedMap(key) {
+  let ret = this[key];
+  if (!ret) {
+    if (this.parent) {
+      ret = this[key] = Object.create(getOrCreateInheritedMap.call(this.parent, key));
+    } else {
+      ret = this[key] = Object.create(null);
+    }
+  }
+  return ret;
+}
+
+function getInheritedMap(key) {
+  let pointer = this;
+  while (pointer) {
+    if (pointer[key]) {
+      return pointer[key];
+    }
+    pointer = pointer.parent;
+  }
+}
+
 function memberProperty(name) {
   return '_' + name;
 }

From bab0092319fd950192ea8a8994fbe5da87e2b3fd Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 19:38:07 -0400
Subject: [PATCH 16/39] encapsulate meta.listeners

---
 packages/ember-metal/lib/events.js        | 38 +++++------------------
 packages/ember-metal/lib/meta.js          | 38 ++++++++++++++++++-----
 packages/ember-metal/tests/events_test.js |  4 +--
 3 files changed, 40 insertions(+), 40 deletions(-)

diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index 13623428963..2056239c24f 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -52,36 +52,12 @@ function indexOf(array, target, method) {
 }
 
 function actionsFor(obj, eventName) {
-  var meta = metaFor(obj, true);
-  var actions;
-  var listeners = meta.listeners;
-
-  if (!listeners) {
-    listeners = meta.listeners = Object.create(null);
-    listeners.__source__ = obj;
-  } else if (listeners.__source__ !== obj) {
-    // setup inherited copy of the listeners object
-    listeners = meta.listeners = Object.create(listeners);
-    listeners.__source__ = obj;
-  }
-
-  actions = listeners[eventName];
-
-  // if there are actions, but the eventName doesn't exist in our listeners, then copy them from the prototype
-  if (actions && actions.__source__ !== obj) {
-    actions = listeners[eventName] = listeners[eventName].slice();
-    actions.__source__ = obj;
-  } else if (!actions) {
-    actions = listeners[eventName] = [];
-    actions.__source__ = obj;
-  }
-
-  return actions;
+  return metaFor(obj, true).getOrCreateListeners(eventName);
 }
 
 export function accumulateListeners(obj, eventName, otherActions) {
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.listeners && meta.listeners[eventName];
+  var actions = meta && meta.getListeners(eventName);
 
   if (!actions) { return; }
 
@@ -180,7 +156,7 @@ export function removeListener(obj, eventName, target, method) {
     _removeListener(target, method);
   } else {
     var meta = obj['__ember_meta__'];
-    var actions = meta && meta.listeners && meta.listeners[eventName];
+    var actions = meta && meta.getListeners(eventName);
 
     if (!actions) { return; }
     for (var i = actions.length - 3; i >= 0; i -= 3) {
@@ -282,7 +258,7 @@ export function suspendListeners(obj, eventNames, target, method, callback) {
   @param obj
 */
 export function watchedEvents(obj) {
-  var listeners = obj['__ember_meta__'].listeners;
+  var listeners = obj['__ember_meta__'].getAllListeners();
   var ret = [];
 
   if (listeners) {
@@ -314,7 +290,7 @@ export function watchedEvents(obj) {
 export function sendEvent(obj, eventName, params, actions) {
   if (!actions) {
     var meta = obj['__ember_meta__'];
-    actions = meta && meta.listeners && meta.listeners[eventName];
+    actions = meta && meta.getListeners(eventName);
   }
 
   if (!actions) { return; }
@@ -354,7 +330,7 @@ export function sendEvent(obj, eventName, params, actions) {
 */
 export function hasListeners(obj, eventName) {
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.listeners && meta.listeners[eventName];
+  var actions = meta && meta.getListeners(eventName);
 
   return !!(actions && actions.length);
 }
@@ -369,7 +345,7 @@ export function hasListeners(obj, eventName) {
 export function listenersFor(obj, eventName) {
   var ret = [];
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.listeners && meta.listeners[eventName];
+  var actions = meta && meta.getListeners(eventName);
 
   if (!actions) { return ret; }
 
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 67160a0d593..9a2301bdbc7 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -14,7 +14,8 @@ let members = {
   watching: inheritedMap,
   mixins: inheritedMap,
   bindings: inheritedMap,
-  values: inheritedMap
+  values: inheritedMap,
+  listeners: inheritedMapOfLists
 };
 
 let memberNames = Object.keys(members);
@@ -32,12 +33,6 @@ function Meta(obj, parentMeta) {
   // map of maps, with two-level prototypical inheritance, cloned on access
   this.deps = undefined;
 
-  // map from keys to lists. Has own __source__ property that's used
-  // to distinguish whether it is being inherited or not. Each list
-  // also has a __source__property. Both levels are inherited on
-  // demand with o_create.
-  this.listeners = undefined;
-
   // instance of ChainNode, inherited on demand via ChainNode.copy
   this.chains = undefined;
 
@@ -135,6 +130,35 @@ function getInheritedMap(key) {
   }
 }
 
+// Implements a member that provides a lazily created mapping from
+// keys to lists, with inheritance at both levels.
+function inheritedMapOfLists(name, Meta) {
+  let key = memberProperty(name);
+  let capitalized = capitalize(name);
+
+  Meta.prototype['getOrCreate' + capitalized] = function(subkey) {
+    let map = getOrCreateInheritedMap.call(this, key);
+    let list = map[subkey];
+    if (!list) {
+      list = map[subkey] = [];
+    } else if (!Object.hasOwnProperty.call(map, subkey)) {
+      list = map[subkey] = list.slice();
+    }
+    return list;
+  };
+
+  Meta.prototype['get' + capitalized] = function(subkey) {
+    let map = getInheritedMap.call(this, key);
+    if (map) {
+      return map[subkey];
+    }
+  };
+
+  Meta.prototype['getAll' + capitalized] = function() {
+    return getInheritedMap.call(this, key);
+  };
+}
+
 function memberProperty(name) {
   return '_' + name;
 }
diff --git a/packages/ember-metal/tests/events_test.js b/packages/ember-metal/tests/events_test.js
index d53334fa804..f118d9b653c 100644
--- a/packages/ember-metal/tests/events_test.js
+++ b/packages/ember-metal/tests/events_test.js
@@ -205,7 +205,7 @@ QUnit.test('while suspended, it should not be possible to add a duplicate listen
   suspendListener(obj, 'event!', target, target.method, callback);
 
   equal(target.count, 1, 'should invoke');
-  equal(meta(obj).listeners['event!'].length, 3, 'a duplicate listener wasn\'t added');
+  equal(meta(obj).getListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
 
   // now test suspendListeners...
 
@@ -214,7 +214,7 @@ QUnit.test('while suspended, it should not be possible to add a duplicate listen
   suspendListeners(obj, ['event!'], target, target.method, callback);
 
   equal(target.count, 2, 'should have invoked again');
-  equal(meta(obj).listeners['event!'].length, 3, 'a duplicate listener wasn\'t added');
+  equal(meta(obj).getListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
 });
 
 QUnit.test('a listener can be added as part of a mixin', function() {

From 9b51c9ef0baa59be07898ba7091d89bdf5a47f00 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 19:50:00 -0400
Subject: [PATCH 17/39] encapsulate meta.deps

---
 packages/ember-metal/lib/dependent_keys.js  | 41 ++-------------------
 packages/ember-metal/lib/meta.js            | 36 ++++++++++++++++--
 packages/ember-metal/lib/property_events.js |  6 +--
 packages/ember-metal/tests/alias_test.js    |  4 +-
 4 files changed, 41 insertions(+), 46 deletions(-)

diff --git a/packages/ember-metal/lib/dependent_keys.js b/packages/ember-metal/lib/dependent_keys.js
index 9d93ed650f4..9976c8251be 100644
--- a/packages/ember-metal/lib/dependent_keys.js
+++ b/packages/ember-metal/lib/dependent_keys.js
@@ -17,50 +17,19 @@ import {
 // DEPENDENT KEYS
 //
 
-// data structure:
-//  meta.deps = {
-//    'depKey': {
-//      'keyName': count,
-//    }
-//  }
-
-/*
-  This function returns a map of unique dependencies for a
-  given object and key.
-*/
-function keysForDep(depsMeta, depKey) {
-  var keys = depsMeta[depKey];
-  if (!keys) {
-    // if there are no dependencies yet for a the given key
-    // create a new empty list of dependencies for the key
-    keys = depsMeta[depKey] = {};
-  } else if (!depsMeta.hasOwnProperty(depKey)) {
-    // otherwise if the dependency list is inherited from
-    // a superclass, clone the hash
-    keys = depsMeta[depKey] = Object.create(keys);
-  }
-  return keys;
-}
-
-function metaForDeps(meta) {
-  return keysForDep(meta, 'deps');
-}
-
 export function addDependentKeys(desc, obj, keyName, meta) {
   // the descriptor has a list of dependent keys, so
   // add all of its dependent keys.
-  var depsMeta, idx, len, depKey, keys;
+  var idx, len, depKey, keys;
   var depKeys = desc._dependentKeys;
   if (!depKeys) {
     return;
   }
 
-  depsMeta = metaForDeps(meta);
-
   for (idx = 0, len = depKeys.length; idx < len; idx++) {
     depKey = depKeys[idx];
     // Lookup keys meta for depKey
-    keys = keysForDep(depsMeta, depKey);
+    keys = meta.getOrCreateDeps(depKey);
     // Increment the number of times depKey depends on keyName.
     keys[keyName] = (keys[keyName] || 0) + 1;
     // Watch the depKey
@@ -72,17 +41,15 @@ export function removeDependentKeys(desc, obj, keyName, meta) {
   // the descriptor has a list of dependent keys, so
   // remove all of its dependent keys.
   var depKeys = desc._dependentKeys;
-  var depsMeta, idx, len, depKey, keys;
+  var idx, len, depKey, keys;
   if (!depKeys) {
     return;
   }
 
-  depsMeta = metaForDeps(meta);
-
   for (idx = 0, len = depKeys.length; idx < len; idx++) {
     depKey = depKeys[idx];
     // Lookup keys meta for depKey
-    keys = keysForDep(depsMeta, depKey);
+    keys = meta.getOrCreateDeps(depKey);
     // Decrement the number of times depKey depends on keyName.
     keys[keyName] = (keys[keyName] || 0) - 1;
     // Unwatch the depKey
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 9a2301bdbc7..154c543e22a 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -15,7 +15,8 @@ let members = {
   mixins: inheritedMap,
   bindings: inheritedMap,
   values: inheritedMap,
-  listeners: inheritedMapOfLists
+  listeners: inheritedMapOfLists,
+  deps: inheritedMapOfMaps
 };
 
 let memberNames = Object.keys(members);
@@ -30,9 +31,6 @@ function Meta(obj, parentMeta) {
   // from instance's own meta
   this.source = obj;
 
-  // map of maps, with two-level prototypical inheritance, cloned on access
-  this.deps = undefined;
-
   // instance of ChainNode, inherited on demand via ChainNode.copy
   this.chains = undefined;
 
@@ -159,6 +157,36 @@ function inheritedMapOfLists(name, Meta) {
   };
 }
 
+
+// Implements a member that provides a lazily created map of maps,
+// with inheritance at both levels.
+function inheritedMapOfMaps(name, Meta) {
+  let key = memberProperty(name);
+  let capitalized = capitalize(name);
+
+  Meta.prototype['getOrCreate' + capitalized] = function(subkey) {
+    let outerMap = getOrCreateInheritedMap.call(this, key);
+    let innerMap = outerMap[subkey];
+    if (!innerMap) {
+      innerMap = outerMap[subkey] = Object.create(null);
+    } else if (!Object.hasOwnProperty.call(outerMap, subkey)) {
+      innerMap = outerMap[subkey] = Object.create(innerMap);
+    }
+    return innerMap;
+  };
+
+  Meta.prototype['get' + capitalized] = function(subkey) {
+    let map = getInheritedMap.call(this, key);
+    if (map) {
+      return map[subkey];
+    }
+  };
+
+  Meta.prototype['getAll' + capitalized] = function() {
+    return getInheritedMap.call(this, key);
+  };
+}
+
 function memberProperty(name) {
   return '_' + name;
 }
diff --git a/packages/ember-metal/lib/property_events.js b/packages/ember-metal/lib/property_events.js
index 2a259bd0b74..f588def99e5 100644
--- a/packages/ember-metal/lib/property_events.js
+++ b/packages/ember-metal/lib/property_events.js
@@ -98,7 +98,7 @@ function propertyDidChange(obj, keyName) {
     return;
   }
 
-  if (m && m.deps && m.deps[keyName]) {
+  if (m && m.getDeps(keyName)) {
     dependentKeysDidChange(obj, keyName, m);
   }
 
@@ -112,7 +112,7 @@ function dependentKeysWillChange(obj, depKey, meta) {
   if (obj.isDestroying) { return; }
 
   var deps;
-  if (meta && meta.deps && (deps = meta.deps[depKey])) {
+  if (meta && (deps = meta.getDeps(depKey))) {
     var seen = WILL_SEEN;
     var top = !seen;
 
@@ -133,7 +133,7 @@ function dependentKeysDidChange(obj, depKey, meta) {
   if (obj.isDestroying) { return; }
 
   var deps;
-  if (meta && meta.deps && (deps = meta.deps[depKey])) {
+  if (meta && (deps = meta.getDeps(depKey))) {
     var seen = DID_SEEN;
     var top = !seen;
 
diff --git a/packages/ember-metal/tests/alias_test.js b/packages/ember-metal/tests/alias_test.js
index 4efe77b35b6..8078e6ef0d3 100644
--- a/packages/ember-metal/tests/alias_test.js
+++ b/packages/ember-metal/tests/alias_test.js
@@ -37,9 +37,9 @@ QUnit.test('basic lifecycle', function() {
   defineProperty(obj, 'bar', alias('foo.faz'));
   var m = meta(obj);
   addObserver(obj, 'bar', incrementCount);
-  equal(m.deps['foo.faz'].bar, 1);
+  equal(m.getDeps('foo.faz').bar, 1);
   removeObserver(obj, 'bar', incrementCount);
-  equal(m.deps['foo.faz'].bar, 0);
+  equal(m.getDeps('foo.faz').bar, 0);
 });
 
 QUnit.test('begins watching alt key as soon as alias is watched', function() {

From 1fd3eb531c513f4677c8c168708691096abf0d57 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 20:22:56 -0400
Subject: [PATCH 18/39] encapsulate meta.chainWatchers

---
 packages/ember-metal/lib/chains.js            | 15 +++-------
 packages/ember-metal/lib/computed.js          |  5 ++--
 packages/ember-metal/lib/meta.js              | 28 +++++++++++++------
 packages/ember-metal/lib/property_events.js   | 20 ++++++-------
 .../ember-metal/tests/watching/watch_test.js  |  8 +++---
 5 files changed, 40 insertions(+), 36 deletions(-)

diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index 9884bc925ea..93ff0ce094f 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -137,13 +137,7 @@ function addChainWatcher(obj, keyName, node) {
   }
 
   let m = metaFor(obj);
-
-  if (m.chainWatchers === undefined || m.chainWatchers.obj !== obj) {
-    m.chainWatchers = new ChainWatchers(obj);
-  }
-
-  m.chainWatchers.add(keyName, node);
-
+  m.getOrCreateChainWatchers(ChainWatchers).add(keyName, node);
   watchKey(obj, keyName, m);
 }
 
@@ -154,15 +148,14 @@ function removeChainWatcher(obj, keyName, node) {
 
   let m = obj.__ember_meta__;
 
-  if (!m ||
-      m.chainWatchers === undefined || m.chainWatchers.obj !== obj) {
+  if (!m || !m.getChainWatchers()) {
     return;
   }
 
   // make meta writable
   m = metaFor(obj);
 
-  m.chainWatchers.remove(keyName, node);
+  m.getChainWatchers().remove(keyName, node);
 
   unwatchKey(obj, keyName, m);
 }
@@ -425,7 +418,7 @@ export function finishChains(obj) {
   let m = obj.__ember_meta__;
   if (m) {
     // finish any current chains node watchers that reference obj
-    let chainWatchers = m.chainWatchers;
+    let chainWatchers = m.getChainWatchers();
     if (chainWatchers) {
       chainWatchers.revalidateAll();
     }
diff --git a/packages/ember-metal/lib/computed.js b/packages/ember-metal/lib/computed.js
index 2ba3892f01e..e32240b7b0c 100644
--- a/packages/ember-metal/lib/computed.js
+++ b/packages/ember-metal/lib/computed.js
@@ -324,8 +324,9 @@ ComputedPropertyPrototype.get = function(obj, keyName) {
       cache[keyName] = ret;
     }
 
-    if (meta.chainWatchers) {
-      meta.chainWatchers.revalidate(keyName);
+    let chainWatchers = meta.getChainWatchers();
+    if (chainWatchers) {
+      chainWatchers.revalidate(keyName);
     }
     addDependentKeys(this, obj, keyName, meta);
   } else {
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 154c543e22a..8852f368fd7 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -16,7 +16,8 @@ let members = {
   bindings: inheritedMap,
   values: inheritedMap,
   listeners: inheritedMapOfLists,
-  deps: inheritedMapOfMaps
+  deps: inheritedMapOfMaps,
+  chainWatchers: ownCustomObject
 };
 
 let memberNames = Object.keys(members);
@@ -27,18 +28,12 @@ function Meta(obj, parentMeta) {
     this[memberProperty(memberNames[i])] = undefined;
   }
 
-  // used only internally by meta() to distinguish meta-from-prototype
-  // from instance's own meta
+  // used only internally
   this.source = obj;
 
   // instance of ChainNode, inherited on demand via ChainNode.copy
   this.chains = undefined;
 
-  // instanceof ChainWatchers. Created on demand with a fresh new
-  // ChainWatchers at each level in prototype chain, by testing
-  // m.chainWatchers.obj.
-  this.chainWatchers = undefined;
-
   // when meta(obj).proto === obj, the object is intended to be only a
   // prototype and doesn't need to actually be observable itself
   this.proto = undefined;
@@ -187,6 +182,23 @@ function inheritedMapOfMaps(name, Meta) {
   };
 }
 
+// Implements a member that provides a non-heritable, lazily-created
+// object using the class you provide.
+function ownCustomObject(name, Meta) {
+  let key = memberProperty(name);
+  let capitalized = capitalize(name);
+  Meta.prototype['getOrCreate' + capitalized] = function(Klass) {
+    let ret = this[key];
+    if (!ret) {
+      ret = this[key] = new Klass(this.source);
+    }
+    return ret;
+  };
+  Meta.prototype['get' + capitalized] = function() {
+    return this[key];
+  };
+}
+
 function memberProperty(name) {
   return '_' + name;
 }
diff --git a/packages/ember-metal/lib/property_events.js b/packages/ember-metal/lib/property_events.js
index f588def99e5..42af019fd05 100644
--- a/packages/ember-metal/lib/property_events.js
+++ b/packages/ember-metal/lib/property_events.js
@@ -191,26 +191,24 @@ function iterDeps(method, obj, deps, depKey, seen, meta) {
 }
 
 function chainsWillChange(obj, keyName, m) {
-  if (m.chainWatchers === undefined || m.chainWatchers.obj !== obj) {
-    return;
+  let c = m.getChainWatchers();
+  if (c) {
+    c.notify(keyName, false, propertyWillChange);
   }
-
-  m.chainWatchers.notify(keyName, false, propertyWillChange);
 }
 
 function chainsDidChange(obj, keyName, m) {
-  if (m.chainWatchers === undefined || m.chainWatchers.obj !== obj) {
-    return;
+  let c = m.getChainWatchers();
+  if (c) {
+    c.notify(keyName, true, propertyDidChange);
   }
-
-  m.chainWatchers.notify(keyName, true, propertyDidChange);
 }
 
 function overrideChains(obj, keyName, m) {
-  if (m.chainWatchers === undefined || m.chainWatchers.obj !== obj) {
-    return;
+  let c = m.getChainWatchers();
+  if (c) {
+    c.revalidate(keyName);
   }
-  m.chainWatchers.revalidate(keyName);
 }
 
 /**
diff --git a/packages/ember-metal/tests/watching/watch_test.js b/packages/ember-metal/tests/watching/watch_test.js
index e4a6121d72b..5b0e16ef436 100644
--- a/packages/ember-metal/tests/watching/watch_test.js
+++ b/packages/ember-metal/tests/watching/watch_test.js
@@ -206,12 +206,12 @@ QUnit.test('when watching a global object, destroy should remove chain watchers
   var chainNode = Ember.meta(obj).chains._chains.Global._chains.foo;
 
   equal(meta_Global.peekWatching('foo'), 1, 'should be watching foo');
-  equal(meta_Global.chainWatchers.has('foo', chainNode), true, 'should have chain watcher');
+  equal(meta_Global.getChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
 
   destroy(obj);
 
   equal(meta_Global.peekWatching('foo'), 0, 'should not be watching foo');
-  equal(meta_Global.chainWatchers.has('foo', chainNode), false, 'should not have chain watcher');
+  equal(meta_Global.getChainWatchers().has('foo', chainNode), false, 'should not have chain watcher');
 
   lookup['Global'] = Global = null; // reset
 });
@@ -228,12 +228,12 @@ QUnit.test('when watching another object, destroy should remove chain watchers f
   var chainNode = Ember.meta(objA).chains._chains.b._chains.foo;
 
   equal(meta_objB.peekWatching('foo'), 1, 'should be watching foo');
-  equal(meta_objB.chainWatchers.has('foo', chainNode), true, 'should have chain watcher');
+  equal(meta_objB.getChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
 
   destroy(objA);
 
   equal(meta_objB.peekWatching('foo'), 0, 'should not be watching foo');
-  equal(meta_objB.chainWatchers.has('foo', chainNode), false, 'should not have chain watcher');
+  equal(meta_objB.getChainWatchers().has('foo', chainNode), false, 'should not have chain watcher');
 });
 
 // TESTS for length property

From a3f86cc1cc6c4724a04d7264c823cf060c315947 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 20:53:58 -0400
Subject: [PATCH 19/39] encapsulate meta.chains

---
 packages/ember-metal/lib/chains.js            | 17 ++++---
 packages/ember-metal/lib/meta.js              | 49 +++++++++++++------
 packages/ember-metal/lib/watch_path.js        | 13 ++---
 packages/ember-metal/lib/watching.js          |  2 +-
 packages/ember-metal/tests/chains_test.js     |  3 +-
 .../ember-metal/tests/watching/watch_test.js  |  4 +-
 6 files changed, 55 insertions(+), 33 deletions(-)

diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index 93ff0ce094f..80b3f9c720b 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -131,13 +131,17 @@ export function flushPendingChains() {
   );
 }
 
+function makeChainWatcher(obj) {
+  return new ChainWatchers(obj);
+}
+
 function addChainWatcher(obj, keyName, node) {
   if (!isObject(obj)) {
     return;
   }
 
   let m = metaFor(obj);
-  m.getOrCreateChainWatchers(ChainWatchers).add(keyName, node);
+  m.getOrCreateChainWatchers(makeChainWatcher).add(keyName, node);
   watchKey(obj, keyName, m);
 }
 
@@ -417,16 +421,17 @@ export function finishChains(obj) {
   // We only create meta if we really have to
   let m = obj.__ember_meta__;
   if (m) {
+    m = metaFor(obj);
+
     // finish any current chains node watchers that reference obj
     let chainWatchers = m.getChainWatchers();
     if (chainWatchers) {
       chainWatchers.revalidateAll();
     }
-    // copy chains from prototype
-    let chains = m.chains;
-    if (chains && chains.value() !== obj) {
-      // need to check if meta is writable
-      metaFor(obj).chains = chains.copy(obj);
+    // ensure that if we have inherited any chains they have been
+    // copied onto our own meta.
+    if (m.getChains()) {
+      m.getOrCreateChains();
     }
   }
 }
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 8852f368fd7..727c63c9766 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -17,7 +17,8 @@ let members = {
   values: inheritedMap,
   listeners: inheritedMapOfLists,
   deps: inheritedMapOfMaps,
-  chainWatchers: ownCustomObject
+  chainWatchers: ownCustomObject,
+  chains: inheritedCustomObject
 };
 
 let memberNames = Object.keys(members);
@@ -31,9 +32,6 @@ function Meta(obj, parentMeta) {
   // used only internally
   this.source = obj;
 
-  // instance of ChainNode, inherited on demand via ChainNode.copy
-  this.chains = undefined;
-
   // when meta(obj).proto === obj, the object is intended to be only a
   // prototype and doesn't need to actually be observable itself
   this.proto = undefined;
@@ -86,11 +84,11 @@ function inheritedMap(name, Meta) {
   };
 
   Meta.prototype['get' + capitalized] = function() {
-    return getInheritedMap.call(this, key);
+    return getInherited.call(this, key);
   };
 
   Meta.prototype['peek' + capitalized] = function(subkey) {
-    let map = getInheritedMap.call(this, key);
+    let map = getInherited.call(this, key);
     if (map) {
       return map[subkey];
     }
@@ -113,7 +111,7 @@ function getOrCreateInheritedMap(key) {
   return ret;
 }
 
-function getInheritedMap(key) {
+function getInherited(key) {
   let pointer = this;
   while (pointer) {
     if (pointer[key]) {
@@ -141,14 +139,14 @@ function inheritedMapOfLists(name, Meta) {
   };
 
   Meta.prototype['get' + capitalized] = function(subkey) {
-    let map = getInheritedMap.call(this, key);
+    let map = getInherited.call(this, key);
     if (map) {
       return map[subkey];
     }
   };
 
   Meta.prototype['getAll' + capitalized] = function() {
-    return getInheritedMap.call(this, key);
+    return getInherited.call(this, key);
   };
 }
 
@@ -171,26 +169,26 @@ function inheritedMapOfMaps(name, Meta) {
   };
 
   Meta.prototype['get' + capitalized] = function(subkey) {
-    let map = getInheritedMap.call(this, key);
+    let map = getInherited.call(this, key);
     if (map) {
       return map[subkey];
     }
   };
 
   Meta.prototype['getAll' + capitalized] = function() {
-    return getInheritedMap.call(this, key);
+    return getInherited.call(this, key);
   };
 }
 
 // Implements a member that provides a non-heritable, lazily-created
-// object using the class you provide.
+// object using the method you provide.
 function ownCustomObject(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
-  Meta.prototype['getOrCreate' + capitalized] = function(Klass) {
+  Meta.prototype['getOrCreate' + capitalized] = function(create) {
     let ret = this[key];
     if (!ret) {
-      ret = this[key] = new Klass(this.source);
+      ret = this[key] = create(this.source);
     }
     return ret;
   };
@@ -199,6 +197,29 @@ function ownCustomObject(name, Meta) {
   };
 }
 
+// Implements a member that provides an inheritable, lazily-created
+// object using the method you provide. We will derived children from
+// their parents by calling your object's `copy()` method.
+function inheritedCustomObject(name, Meta) {
+  let key = memberProperty(name);
+  let capitalized = capitalize(name);
+  let getOrCreate = Meta.prototype['getOrCreate' + capitalized] = function(create) {
+    let ret = this[key];
+    if (!ret) {
+      if (this.parent) {
+        ret = this[key] = getOrCreate.call(this.parent, create).copy(this.source);
+      } else {
+        ret = this[key] = create(this.source);
+      }
+    }
+    return ret;
+  };
+  Meta.prototype['get' + capitalized] = function() {
+    return getInherited.call(this, key);
+  };
+}
+
+
 function memberProperty(name) {
   return '_' + name;
 }
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index c40194b5af5..7773793b3f5 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -7,14 +7,11 @@ import { ChainNode } from 'ember-metal/chains';
 // chains inherited from the proto they will be cloned and reconfigured for
 // the current object.
 function chainsFor(obj, meta) {
-  var m = meta || metaFor(obj);
-  var ret = m.chains;
-  if (!ret) {
-    ret = m.chains = new ChainNode(null, null, obj);
-  } else if (ret.value() !== obj) {
-    ret = m.chains = ret.copy(obj);
-  }
-  return ret;
+  return (meta || metaFor(obj)).getOrCreateChains(makeChainNode);
+}
+
+function makeChainNode(obj) {
+  return new ChainNode(null, null, obj);
 }
 
 export function watchPath(obj, keyPath, meta) {
diff --git a/packages/ember-metal/lib/watching.js b/packages/ember-metal/lib/watching.js
index 74c247d8033..1a470b9fa55 100644
--- a/packages/ember-metal/lib/watching.js
+++ b/packages/ember-metal/lib/watching.js
@@ -81,7 +81,7 @@ export function destroy(obj) {
   if (meta) {
     obj['__ember_meta__'] = null;
     // remove chainWatchers to remove circular references that would prevent GC
-    node = meta.chains;
+    node = meta.getChains();
     if (node) {
       NODE_STACK.push(node);
       // process tree
diff --git a/packages/ember-metal/tests/chains_test.js b/packages/ember-metal/tests/chains_test.js
index 774b62c1472..446612f0bb1 100644
--- a/packages/ember-metal/tests/chains_test.js
+++ b/packages/ember-metal/tests/chains_test.js
@@ -14,8 +14,7 @@ QUnit.test('finishChains should properly copy chains from prototypes to instance
 
   var childObj = Object.create(obj);
   finishChains(childObj);
-
-  ok(obj['__ember_meta__'].chains !== childObj['__ember_meta__'].chains, 'The chains object is copied');
+  ok(obj['__ember_meta__'].getChains() !== childObj['__ember_meta__'].getChains(), 'The chains object is copied');
 });
 
 
diff --git a/packages/ember-metal/tests/watching/watch_test.js b/packages/ember-metal/tests/watching/watch_test.js
index 5b0e16ef436..199a130232b 100644
--- a/packages/ember-metal/tests/watching/watch_test.js
+++ b/packages/ember-metal/tests/watching/watch_test.js
@@ -203,7 +203,7 @@ QUnit.test('when watching a global object, destroy should remove chain watchers
   watch(obj, 'Global.foo');
 
   var meta_Global = Ember.meta(Global);
-  var chainNode = Ember.meta(obj).chains._chains.Global._chains.foo;
+  var chainNode = Ember.meta(obj).getChains()._chains.Global._chains.foo;
 
   equal(meta_Global.peekWatching('foo'), 1, 'should be watching foo');
   equal(meta_Global.getChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
@@ -225,7 +225,7 @@ QUnit.test('when watching another object, destroy should remove chain watchers f
   watch(objA, 'b.foo');
 
   var meta_objB = Ember.meta(objB);
-  var chainNode = Ember.meta(objA).chains._chains.b._chains.foo;
+  var chainNode = Ember.meta(objA).getChains()._chains.b._chains.foo;
 
   equal(meta_objB.peekWatching('foo'), 1, 'should be watching foo');
   equal(meta_objB.getChainWatchers().has('foo', chainNode), true, 'should have chain watcher');

From 93743c1de5324d2dc5c7ad9e82a75c9adc7ef908 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 20:58:19 -0400
Subject: [PATCH 20/39] break the meta prototype chain!

---
 packages/ember-metal/lib/meta.js | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 727c63c9766..f5a31717cd2 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -285,17 +285,7 @@ export function meta(obj, writable) {
       ret.getOrCreateValues();
     }
   } else if (ret.source !== obj) {
-    // temporary dance until I can eliminate remaining uses of
-    // prototype chain
-    let newRet = Object.create(ret);
-    newRet.parent = ret;
-    for (let i = 0; i < memberNames.length; i++) {
-      newRet[memberProperty(memberNames[i])] = undefined;
-    }
-    ret = newRet;
-    // end temporary dance
-
-    ret.source    = obj;
+    ret = new Meta(obj, ret);
   }
   obj.__ember_meta__ = ret;
   return ret;

From d51a492e0b26a3d7f1fb90a9bd0c4ffb84eb458f Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:09:32 -0400
Subject: [PATCH 21/39] better naming

---
 packages/ember-metal/lib/chains.js               |  2 +-
 packages/ember-metal/lib/computed.js             | 12 ++++++------
 packages/ember-metal/lib/meta.js                 |  7 +++----
 packages/ember-runtime/lib/system/core_object.js |  2 +-
 4 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index 80b3f9c720b..d4bbfe62e53 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -219,7 +219,7 @@ function lazyGet(obj, key) {
     return get(obj, key);
   // Otherwise attempt to get the cached value of the computed property
   } else {
-    let cache = meta.getCache();
+    let cache = meta.readableCache();
     if (cache && key in cache) {
       return cache[key];
     }
diff --git a/packages/ember-metal/lib/computed.js b/packages/ember-metal/lib/computed.js
index e32240b7b0c..29b7d1e6b75 100644
--- a/packages/ember-metal/lib/computed.js
+++ b/packages/ember-metal/lib/computed.js
@@ -267,7 +267,7 @@ ComputedPropertyPrototype.didChange = function(obj, keyName) {
   // the cached value set by the setter
   if (this._cacheable && this._suspended !== obj) {
     let meta = metaFor(obj);
-    let cache = meta.getCache();
+    let cache = meta.readableCache();
     if (cache && cache[keyName] !== undefined) {
       cache[keyName] = undefined;
       removeDependentKeys(this, obj, keyName, meta);
@@ -306,7 +306,7 @@ ComputedPropertyPrototype.get = function(obj, keyName) {
   var ret, cache, meta;
   if (this._cacheable) {
     meta = metaFor(obj);
-    cache = meta.getOrCreateCache();
+    cache = meta.writableCache();
 
     var result = cache[keyName];
 
@@ -400,7 +400,7 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
   var cacheable      = this._cacheable;
   var setter         = this._setter;
   var meta           = metaFor(obj, cacheable);
-  var cache          = meta.getCache();
+  var cache          = meta.readableCache();
   var hadCachedValue = false;
 
   var cachedValue, ret;
@@ -440,7 +440,7 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
       addDependentKeys(this, obj, keyName, meta);
     }
     if (!cache) {
-      cache = meta.getOrCreateCache();
+      cache = meta.writableCache();
     }
     if (ret === undefined) {
       cache[keyName] = UNDEFINED;
@@ -459,7 +459,7 @@ ComputedPropertyPrototype._set = function computedPropertySet(obj, keyName, valu
 /* called before property is overridden */
 ComputedPropertyPrototype.teardown = function(obj, keyName) {
   var meta = metaFor(obj);
-  let cache = meta.getCache();
+  let cache = meta.readableCache();
   if (cache) {
     if (keyName in cache) {
       removeDependentKeys(this, obj, keyName, meta);
@@ -559,7 +559,7 @@ export default function computed(func) {
 */
 function cacheFor(obj, key) {
   var meta = obj['__ember_meta__'];
-  var cache = meta && meta.getCache();
+  var cache = meta && meta.readableCache();
   var ret = cache && cache[key];
 
   if (ret === UNDEFINED) {
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index f5a31717cd2..c399ce7faa5 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -53,15 +53,14 @@ function Meta(obj, parentMeta) {
 
 
 // Implements a member that is a lazily created, non-inheritable
-// POJO. For member `thing` you get methods `getThing` and
-// `getOrCreateThing`.
+// POJO.
 function ownMap(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
-  Meta.prototype['getOrCreate' + capitalized] = function() {
+  Meta.prototype['writable' + capitalized] = function() {
     return getOrCreateOwnMap.call(this, key);
   };
-  Meta.prototype['get' + capitalized] = function() { return this[key]; };
+  Meta.prototype['readable' + capitalized] = function() { return this[key]; };
 }
 
 function getOrCreateOwnMap(key) {
diff --git a/packages/ember-runtime/lib/system/core_object.js b/packages/ember-runtime/lib/system/core_object.js
index d2a8fef8168..9b328b8026e 100644
--- a/packages/ember-runtime/lib/system/core_object.js
+++ b/packages/ember-runtime/lib/system/core_object.js
@@ -853,7 +853,7 @@ CoreObject.reopen({
   didDefineProperty(proto, key, value) {
     if (hasCachedComputedProperties === false) { return; }
     if (value instanceof Ember.ComputedProperty) {
-      var cache = Ember.meta(this.constructor).getCache();
+      var cache = Ember.meta(this.constructor).readableCache();
 
       if (cache && cache._computedProperties !== undefined) {
         cache._computedProperties = undefined;

From f216afccb12919bd7dcd60d0b4686f074c12919b Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:15:26 -0400
Subject: [PATCH 22/39] better naming for inheritedMap accessors

---
 packages/ember-metal/lib/meta.js                          | 8 ++++----
 packages/ember-metal/lib/mixin.js                         | 8 ++++----
 packages/ember-metal/lib/properties.js                    | 2 +-
 packages/ember-metal/lib/property_set.js                  | 2 +-
 packages/ember-metal/lib/watch_key.js                     | 8 ++++----
 packages/ember-metal/lib/watch_path.js                    | 4 ++--
 .../ember-metal/tests/accessors/mandatory_setters_test.js | 6 +++---
 packages/ember-runtime/lib/system/core_object.js          | 2 +-
 8 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index c399ce7faa5..80925ccce38 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -78,11 +78,11 @@ function inheritedMap(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
 
-  Meta.prototype['getOrCreate' + capitalized] = function() {
+  Meta.prototype['writable' + capitalized] = function() {
     return getOrCreateInheritedMap.call(this, key);
   };
 
-  Meta.prototype['get' + capitalized] = function() {
+  Meta.prototype['readable' + capitalized] = function() {
     return getInherited.call(this, key);
   };
 
@@ -245,7 +245,7 @@ var EMBER_META_PROPERTY = {
 export var EMPTY_META = new Meta(null);
 
 if (isEnabled('mandatory-setter')) {
-  EMPTY_META.getOrCreateValues();
+  EMPTY_META.writableValues();
 }
 
 /**
@@ -281,7 +281,7 @@ export function meta(obj, writable) {
   if (!ret) {
     ret = new Meta(obj);
     if (isEnabled('mandatory-setter')) {
-      ret.getOrCreateValues();
+      ret.writableValues();
     }
   } else if (ret.source !== obj) {
     ret = new Meta(obj, ret);
diff --git a/packages/ember-metal/lib/mixin.js b/packages/ember-metal/lib/mixin.js
index 3aba637b6f2..1b986b562b3 100644
--- a/packages/ember-metal/lib/mixin.js
+++ b/packages/ember-metal/lib/mixin.js
@@ -74,7 +74,7 @@ superFunction.call(primer, 1, 2);
 superFunction.call(primer, 1, 2, 3);
 
 function mixinsMeta(obj) {
-  return metaFor(obj, true).getOrCreateMixins();
+  return metaFor(obj, true).writableMixins();
 }
 
 function isMethod(obj) {
@@ -309,7 +309,7 @@ var IS_BINDING = /^.+Binding$/;
 
 function detectBinding(obj, key, value, m) {
   if (IS_BINDING.test(key)) {
-    m.getOrCreateBindings()[key] = value;
+    m.writableBindings()[key] = value;
   }
 }
 
@@ -340,7 +340,7 @@ function connectStreamBinding(obj, key, stream) {
 
 function connectBindings(obj, m) {
   // TODO Mixin.apply(instance) should disconnect binding if exists
-  var bindings = m.getBindings();
+  var bindings = m.readableBindings();
   var key, binding, to;
   if (bindings) {
     for (key in bindings) {
@@ -696,7 +696,7 @@ MixinPrototype.keys = function() {
 // TODO: Make Ember.mixin
 Mixin.mixins = function(obj) {
   var m = obj['__ember_meta__'];
-  var mixins = m && m.getMixins();
+  var mixins = m && m.readableMixins();
   var ret = [];
 
   if (!mixins) { return ret; }
diff --git a/packages/ember-metal/lib/properties.js b/packages/ember-metal/lib/properties.js
index abb25b1f0cf..cd7e8b14ec4 100644
--- a/packages/ember-metal/lib/properties.js
+++ b/packages/ember-metal/lib/properties.js
@@ -122,7 +122,7 @@ export function defineProperty(obj, keyName, desc, data, meta) {
 
       if (isEnabled('mandatory-setter')) {
         if (watching) {
-          meta.getOrCreateValues()[keyName] = data;
+          meta.writableValues()[keyName] = data;
           Object.defineProperty(obj, keyName, {
             configurable: true,
             enumerable: true,
diff --git a/packages/ember-metal/lib/property_set.js b/packages/ember-metal/lib/property_set.js
index 2ebbafebd2c..16d591324ed 100644
--- a/packages/ember-metal/lib/property_set.js
+++ b/packages/ember-metal/lib/property_set.js
@@ -81,7 +81,7 @@ export function set(obj, keyName, value, tolerant) {
           ) {
             defineProperty(obj, keyName, null, value); // setup mandatory setter
           } else {
-            meta.getOrCreateValues()[keyName] = value;
+            meta.writableValues()[keyName] = value;
           }
         } else {
           obj[keyName] = value;
diff --git a/packages/ember-metal/lib/watch_key.js b/packages/ember-metal/lib/watch_key.js
index 873b82cd519..2773a61efef 100644
--- a/packages/ember-metal/lib/watch_key.js
+++ b/packages/ember-metal/lib/watch_key.js
@@ -12,7 +12,7 @@ export function watchKey(obj, keyName, meta) {
   if (keyName === 'length' && Array.isArray(obj)) { return; }
 
   var m = meta || metaFor(obj);
-  var watching = m.getOrCreateWatching();
+  var watching = m.writableWatching();
 
   // activate watching first time
   if (!watching[keyName]) {
@@ -48,7 +48,7 @@ if (isEnabled('mandatory-setter')) {
 
     // this x in Y deopts, so keeping it in this function is better;
     if (configurable && isWritable && hasValue && keyName in obj) {
-      m.getOrCreateValues()[keyName] = obj[keyName];
+      m.writableValues()[keyName] = obj[keyName];
       Object.defineProperty(obj, keyName, {
         configurable: true,
         enumerable: Object.prototype.propertyIsEnumerable.call(obj, keyName),
@@ -65,7 +65,7 @@ if (isEnabled('mandatory-setter')) {
 
 export function unwatchKey(obj, keyName, meta) {
   var m = meta || metaFor(obj);
-  var watching = m.getOrCreateWatching();
+  var watching = m.writableWatching();
 
   if (watching[keyName] === 1) {
     watching[keyName] = 0;
@@ -91,7 +91,7 @@ export function unwatchKey(obj, keyName, meta) {
               enumerable: true,
               value: val
             });
-            delete m.getOrCreateValues()[keyName];
+            delete m.writableValues()[keyName];
           },
           get: DEFAULT_GETTER_FUNCTION(keyName)
         });
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index 7773793b3f5..4e9957f9325 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -19,7 +19,7 @@ export function watchPath(obj, keyPath, meta) {
   if (keyPath === 'length' && Array.isArray(obj)) { return; }
 
   var m = meta || metaFor(obj);
-  var watching = m.getOrCreateWatching();
+  var watching = m.writableWatching();
 
   if (!watching[keyPath]) { // activate watching first time
     watching[keyPath] = 1;
@@ -31,7 +31,7 @@ export function watchPath(obj, keyPath, meta) {
 
 export function unwatchPath(obj, keyPath, meta) {
   var m = meta || metaFor(obj);
-  var watching = m.getOrCreateWatching();
+  var watching = m.writableWatching();
 
   if (watching[keyPath] === 1) {
     watching[keyPath] = 0;
diff --git a/packages/ember-metal/tests/accessors/mandatory_setters_test.js b/packages/ember-metal/tests/accessors/mandatory_setters_test.js
index 21df14d4058..3bafd745ae5 100644
--- a/packages/ember-metal/tests/accessors/mandatory_setters_test.js
+++ b/packages/ember-metal/tests/accessors/mandatory_setters_test.js
@@ -8,7 +8,7 @@ QUnit.module('mandatory-setters');
 
 function hasMandatorySetter(object, property) {
   var meta = metaFor(object);
-  let values = meta.getValues();
+  let values = meta.readableValues();
   return values && property in values;
 }
 
@@ -114,7 +114,7 @@ if (isEnabled('mandatory-setter')) {
     });
 
     watch(obj, 'someProp');
-    ok(!('someProp' in meta.getValues()), 'blastix');
+    ok(!('someProp' in meta.readableValues()), 'blastix');
   });
 
   QUnit.test('sets up mandatory-setter if property comes from prototype', function() {
@@ -131,7 +131,7 @@ if (isEnabled('mandatory-setter')) {
     watch(obj2, 'someProp');
     var meta = metaFor(obj2);
 
-    ok(('someProp' in meta.getValues()), 'mandatory setter has been setup');
+    ok(('someProp' in meta.readableValues()), 'mandatory setter has been setup');
 
     expectAssertion(function() {
       obj2.someProp = 'foo-bar';
diff --git a/packages/ember-runtime/lib/system/core_object.js b/packages/ember-runtime/lib/system/core_object.js
index 9b328b8026e..09e4c0ce43f 100644
--- a/packages/ember-runtime/lib/system/core_object.js
+++ b/packages/ember-runtime/lib/system/core_object.js
@@ -104,7 +104,7 @@ function makeCtor() {
           var value = properties[keyName];
 
           if (IS_BINDING.test(keyName)) {
-            m.getOrCreateBindings()[keyName] = value;
+            m.writableBindings()[keyName] = value;
           }
 
           var possibleDesc = this[keyName];

From a4a48544d1b887f8c0547278035d65d65220afd9 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:17:44 -0400
Subject: [PATCH 23/39] better naming for inheritMapOfLists accessors

---
 packages/ember-metal/lib/events.js        | 12 ++++++------
 packages/ember-metal/lib/meta.js          |  4 ++--
 packages/ember-metal/tests/events_test.js |  4 ++--
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index 2056239c24f..fa9a217cc8e 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -52,12 +52,12 @@ function indexOf(array, target, method) {
 }
 
 function actionsFor(obj, eventName) {
-  return metaFor(obj, true).getOrCreateListeners(eventName);
+  return metaFor(obj, true).writableListeners(eventName);
 }
 
 export function accumulateListeners(obj, eventName, otherActions) {
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.getListeners(eventName);
+  var actions = meta && meta.readableListeners(eventName);
 
   if (!actions) { return; }
 
@@ -156,7 +156,7 @@ export function removeListener(obj, eventName, target, method) {
     _removeListener(target, method);
   } else {
     var meta = obj['__ember_meta__'];
-    var actions = meta && meta.getListeners(eventName);
+    var actions = meta && meta.readableListeners(eventName);
 
     if (!actions) { return; }
     for (var i = actions.length - 3; i >= 0; i -= 3) {
@@ -290,7 +290,7 @@ export function watchedEvents(obj) {
 export function sendEvent(obj, eventName, params, actions) {
   if (!actions) {
     var meta = obj['__ember_meta__'];
-    actions = meta && meta.getListeners(eventName);
+    actions = meta && meta.readableListeners(eventName);
   }
 
   if (!actions) { return; }
@@ -330,7 +330,7 @@ export function sendEvent(obj, eventName, params, actions) {
 */
 export function hasListeners(obj, eventName) {
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.getListeners(eventName);
+  var actions = meta && meta.readableListeners(eventName);
 
   return !!(actions && actions.length);
 }
@@ -345,7 +345,7 @@ export function hasListeners(obj, eventName) {
 export function listenersFor(obj, eventName) {
   var ret = [];
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.getListeners(eventName);
+  var actions = meta && meta.readableListeners(eventName);
 
   if (!actions) { return ret; }
 
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 80925ccce38..b9078ced634 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -126,7 +126,7 @@ function inheritedMapOfLists(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
 
-  Meta.prototype['getOrCreate' + capitalized] = function(subkey) {
+  Meta.prototype['writable' + capitalized] = function(subkey) {
     let map = getOrCreateInheritedMap.call(this, key);
     let list = map[subkey];
     if (!list) {
@@ -137,7 +137,7 @@ function inheritedMapOfLists(name, Meta) {
     return list;
   };
 
-  Meta.prototype['get' + capitalized] = function(subkey) {
+  Meta.prototype['readable' + capitalized] = function(subkey) {
     let map = getInherited.call(this, key);
     if (map) {
       return map[subkey];
diff --git a/packages/ember-metal/tests/events_test.js b/packages/ember-metal/tests/events_test.js
index f118d9b653c..ead7da29c05 100644
--- a/packages/ember-metal/tests/events_test.js
+++ b/packages/ember-metal/tests/events_test.js
@@ -205,7 +205,7 @@ QUnit.test('while suspended, it should not be possible to add a duplicate listen
   suspendListener(obj, 'event!', target, target.method, callback);
 
   equal(target.count, 1, 'should invoke');
-  equal(meta(obj).getListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
+  equal(meta(obj).readableListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
 
   // now test suspendListeners...
 
@@ -214,7 +214,7 @@ QUnit.test('while suspended, it should not be possible to add a duplicate listen
   suspendListeners(obj, ['event!'], target, target.method, callback);
 
   equal(target.count, 2, 'should have invoked again');
-  equal(meta(obj).getListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
+  equal(meta(obj).readableListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
 });
 
 QUnit.test('a listener can be added as part of a mixin', function() {

From 2d70d56c3da1b0910d6592dfffc4c380afa19e49 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:19:56 -0400
Subject: [PATCH 24/39] better naming for inheritedMapOfMaps accessors

---
 packages/ember-metal/lib/dependent_keys.js  | 4 ++--
 packages/ember-metal/lib/meta.js            | 4 ++--
 packages/ember-metal/lib/property_events.js | 6 +++---
 packages/ember-metal/tests/alias_test.js    | 4 ++--
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/packages/ember-metal/lib/dependent_keys.js b/packages/ember-metal/lib/dependent_keys.js
index 9976c8251be..6a7990b8fcd 100644
--- a/packages/ember-metal/lib/dependent_keys.js
+++ b/packages/ember-metal/lib/dependent_keys.js
@@ -29,7 +29,7 @@ export function addDependentKeys(desc, obj, keyName, meta) {
   for (idx = 0, len = depKeys.length; idx < len; idx++) {
     depKey = depKeys[idx];
     // Lookup keys meta for depKey
-    keys = meta.getOrCreateDeps(depKey);
+    keys = meta.writableDeps(depKey);
     // Increment the number of times depKey depends on keyName.
     keys[keyName] = (keys[keyName] || 0) + 1;
     // Watch the depKey
@@ -49,7 +49,7 @@ export function removeDependentKeys(desc, obj, keyName, meta) {
   for (idx = 0, len = depKeys.length; idx < len; idx++) {
     depKey = depKeys[idx];
     // Lookup keys meta for depKey
-    keys = meta.getOrCreateDeps(depKey);
+    keys = meta.writableDeps(depKey);
     // Decrement the number of times depKey depends on keyName.
     keys[keyName] = (keys[keyName] || 0) - 1;
     // Unwatch the depKey
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index b9078ced634..21e31b2e767 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -156,7 +156,7 @@ function inheritedMapOfMaps(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
 
-  Meta.prototype['getOrCreate' + capitalized] = function(subkey) {
+  Meta.prototype['writable' + capitalized] = function(subkey) {
     let outerMap = getOrCreateInheritedMap.call(this, key);
     let innerMap = outerMap[subkey];
     if (!innerMap) {
@@ -167,7 +167,7 @@ function inheritedMapOfMaps(name, Meta) {
     return innerMap;
   };
 
-  Meta.prototype['get' + capitalized] = function(subkey) {
+  Meta.prototype['readable' + capitalized] = function(subkey) {
     let map = getInherited.call(this, key);
     if (map) {
       return map[subkey];
diff --git a/packages/ember-metal/lib/property_events.js b/packages/ember-metal/lib/property_events.js
index 42af019fd05..77030a9a7b7 100644
--- a/packages/ember-metal/lib/property_events.js
+++ b/packages/ember-metal/lib/property_events.js
@@ -98,7 +98,7 @@ function propertyDidChange(obj, keyName) {
     return;
   }
 
-  if (m && m.getDeps(keyName)) {
+  if (m && m.readableDeps(keyName)) {
     dependentKeysDidChange(obj, keyName, m);
   }
 
@@ -112,7 +112,7 @@ function dependentKeysWillChange(obj, depKey, meta) {
   if (obj.isDestroying) { return; }
 
   var deps;
-  if (meta && (deps = meta.getDeps(depKey))) {
+  if (meta && (deps = meta.readableDeps(depKey))) {
     var seen = WILL_SEEN;
     var top = !seen;
 
@@ -133,7 +133,7 @@ function dependentKeysDidChange(obj, depKey, meta) {
   if (obj.isDestroying) { return; }
 
   var deps;
-  if (meta && (deps = meta.getDeps(depKey))) {
+  if (meta && (deps = meta.readableDeps(depKey))) {
     var seen = DID_SEEN;
     var top = !seen;
 
diff --git a/packages/ember-metal/tests/alias_test.js b/packages/ember-metal/tests/alias_test.js
index 8078e6ef0d3..546fac0c451 100644
--- a/packages/ember-metal/tests/alias_test.js
+++ b/packages/ember-metal/tests/alias_test.js
@@ -37,9 +37,9 @@ QUnit.test('basic lifecycle', function() {
   defineProperty(obj, 'bar', alias('foo.faz'));
   var m = meta(obj);
   addObserver(obj, 'bar', incrementCount);
-  equal(m.getDeps('foo.faz').bar, 1);
+  equal(m.readableDeps('foo.faz').bar, 1);
   removeObserver(obj, 'bar', incrementCount);
-  equal(m.getDeps('foo.faz').bar, 0);
+  equal(m.readableDeps('foo.faz').bar, 0);
 });
 
 QUnit.test('begins watching alt key as soon as alias is watched', function() {

From d74887952e9899f216f660f1ef0c9e5e77a89f33 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:22:07 -0400
Subject: [PATCH 25/39] better naming for ownCustomObject accessors

---
 packages/ember-metal/lib/chains.js                | 8 ++++----
 packages/ember-metal/lib/computed.js              | 2 +-
 packages/ember-metal/lib/meta.js                  | 4 ++--
 packages/ember-metal/lib/property_events.js       | 6 +++---
 packages/ember-metal/tests/watching/watch_test.js | 8 ++++----
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index d4bbfe62e53..2b5225046ec 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -141,7 +141,7 @@ function addChainWatcher(obj, keyName, node) {
   }
 
   let m = metaFor(obj);
-  m.getOrCreateChainWatchers(makeChainWatcher).add(keyName, node);
+  m.writableChainWatchers(makeChainWatcher).add(keyName, node);
   watchKey(obj, keyName, m);
 }
 
@@ -152,14 +152,14 @@ function removeChainWatcher(obj, keyName, node) {
 
   let m = obj.__ember_meta__;
 
-  if (!m || !m.getChainWatchers()) {
+  if (!m || !m.readableChainWatchers()) {
     return;
   }
 
   // make meta writable
   m = metaFor(obj);
 
-  m.getChainWatchers().remove(keyName, node);
+  m.readableChainWatchers().remove(keyName, node);
 
   unwatchKey(obj, keyName, m);
 }
@@ -424,7 +424,7 @@ export function finishChains(obj) {
     m = metaFor(obj);
 
     // finish any current chains node watchers that reference obj
-    let chainWatchers = m.getChainWatchers();
+    let chainWatchers = m.readableChainWatchers();
     if (chainWatchers) {
       chainWatchers.revalidateAll();
     }
diff --git a/packages/ember-metal/lib/computed.js b/packages/ember-metal/lib/computed.js
index 29b7d1e6b75..00b9b1e1944 100644
--- a/packages/ember-metal/lib/computed.js
+++ b/packages/ember-metal/lib/computed.js
@@ -324,7 +324,7 @@ ComputedPropertyPrototype.get = function(obj, keyName) {
       cache[keyName] = ret;
     }
 
-    let chainWatchers = meta.getChainWatchers();
+    let chainWatchers = meta.readableChainWatchers();
     if (chainWatchers) {
       chainWatchers.revalidate(keyName);
     }
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 21e31b2e767..a89be764295 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -184,14 +184,14 @@ function inheritedMapOfMaps(name, Meta) {
 function ownCustomObject(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
-  Meta.prototype['getOrCreate' + capitalized] = function(create) {
+  Meta.prototype['writable' + capitalized] = function(create) {
     let ret = this[key];
     if (!ret) {
       ret = this[key] = create(this.source);
     }
     return ret;
   };
-  Meta.prototype['get' + capitalized] = function() {
+  Meta.prototype['readable' + capitalized] = function() {
     return this[key];
   };
 }
diff --git a/packages/ember-metal/lib/property_events.js b/packages/ember-metal/lib/property_events.js
index 77030a9a7b7..68a7caf1e33 100644
--- a/packages/ember-metal/lib/property_events.js
+++ b/packages/ember-metal/lib/property_events.js
@@ -191,21 +191,21 @@ function iterDeps(method, obj, deps, depKey, seen, meta) {
 }
 
 function chainsWillChange(obj, keyName, m) {
-  let c = m.getChainWatchers();
+  let c = m.readableChainWatchers();
   if (c) {
     c.notify(keyName, false, propertyWillChange);
   }
 }
 
 function chainsDidChange(obj, keyName, m) {
-  let c = m.getChainWatchers();
+  let c = m.readableChainWatchers();
   if (c) {
     c.notify(keyName, true, propertyDidChange);
   }
 }
 
 function overrideChains(obj, keyName, m) {
-  let c = m.getChainWatchers();
+  let c = m.readableChainWatchers();
   if (c) {
     c.revalidate(keyName);
   }
diff --git a/packages/ember-metal/tests/watching/watch_test.js b/packages/ember-metal/tests/watching/watch_test.js
index 199a130232b..12caede4c19 100644
--- a/packages/ember-metal/tests/watching/watch_test.js
+++ b/packages/ember-metal/tests/watching/watch_test.js
@@ -206,12 +206,12 @@ QUnit.test('when watching a global object, destroy should remove chain watchers
   var chainNode = Ember.meta(obj).getChains()._chains.Global._chains.foo;
 
   equal(meta_Global.peekWatching('foo'), 1, 'should be watching foo');
-  equal(meta_Global.getChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
+  equal(meta_Global.readableChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
 
   destroy(obj);
 
   equal(meta_Global.peekWatching('foo'), 0, 'should not be watching foo');
-  equal(meta_Global.getChainWatchers().has('foo', chainNode), false, 'should not have chain watcher');
+  equal(meta_Global.readableChainWatchers().has('foo', chainNode), false, 'should not have chain watcher');
 
   lookup['Global'] = Global = null; // reset
 });
@@ -228,12 +228,12 @@ QUnit.test('when watching another object, destroy should remove chain watchers f
   var chainNode = Ember.meta(objA).getChains()._chains.b._chains.foo;
 
   equal(meta_objB.peekWatching('foo'), 1, 'should be watching foo');
-  equal(meta_objB.getChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
+  equal(meta_objB.readableChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
 
   destroy(objA);
 
   equal(meta_objB.peekWatching('foo'), 0, 'should not be watching foo');
-  equal(meta_objB.getChainWatchers().has('foo', chainNode), false, 'should not have chain watcher');
+  equal(meta_objB.readableChainWatchers().has('foo', chainNode), false, 'should not have chain watcher');
 });
 
 // TESTS for length property

From dbc712cfd19a8bfa6ede3730ba3642eb199a0bd4 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:25:04 -0400
Subject: [PATCH 26/39] better naming for inheritedCustomObject accessors

---
 packages/ember-metal/lib/chains.js                | 4 ++--
 packages/ember-metal/lib/meta.js                  | 6 +++---
 packages/ember-metal/lib/watch_path.js            | 2 +-
 packages/ember-metal/lib/watching.js              | 2 +-
 packages/ember-metal/tests/chains_test.js         | 2 +-
 packages/ember-metal/tests/watching/watch_test.js | 4 ++--
 6 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index 2b5225046ec..b65db575ac2 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -430,8 +430,8 @@ export function finishChains(obj) {
     }
     // ensure that if we have inherited any chains they have been
     // copied onto our own meta.
-    if (m.getChains()) {
-      m.getOrCreateChains();
+    if (m.readableChains()) {
+      m.writableChains();
     }
   }
 }
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index a89be764295..64937c37762 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -202,18 +202,18 @@ function ownCustomObject(name, Meta) {
 function inheritedCustomObject(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
-  let getOrCreate = Meta.prototype['getOrCreate' + capitalized] = function(create) {
+  let writable = Meta.prototype['writable' + capitalized] = function(create) {
     let ret = this[key];
     if (!ret) {
       if (this.parent) {
-        ret = this[key] = getOrCreate.call(this.parent, create).copy(this.source);
+        ret = this[key] = writable.call(this.parent, create).copy(this.source);
       } else {
         ret = this[key] = create(this.source);
       }
     }
     return ret;
   };
-  Meta.prototype['get' + capitalized] = function() {
+  Meta.prototype['readable' + capitalized] = function() {
     return getInherited.call(this, key);
   };
 }
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index 4e9957f9325..53685bd18b9 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -7,7 +7,7 @@ import { ChainNode } from 'ember-metal/chains';
 // chains inherited from the proto they will be cloned and reconfigured for
 // the current object.
 function chainsFor(obj, meta) {
-  return (meta || metaFor(obj)).getOrCreateChains(makeChainNode);
+  return (meta || metaFor(obj)).writableChains(makeChainNode);
 }
 
 function makeChainNode(obj) {
diff --git a/packages/ember-metal/lib/watching.js b/packages/ember-metal/lib/watching.js
index 1a470b9fa55..301df33ab00 100644
--- a/packages/ember-metal/lib/watching.js
+++ b/packages/ember-metal/lib/watching.js
@@ -81,7 +81,7 @@ export function destroy(obj) {
   if (meta) {
     obj['__ember_meta__'] = null;
     // remove chainWatchers to remove circular references that would prevent GC
-    node = meta.getChains();
+    node = meta.readableChains();
     if (node) {
       NODE_STACK.push(node);
       // process tree
diff --git a/packages/ember-metal/tests/chains_test.js b/packages/ember-metal/tests/chains_test.js
index 446612f0bb1..ec3518078bd 100644
--- a/packages/ember-metal/tests/chains_test.js
+++ b/packages/ember-metal/tests/chains_test.js
@@ -14,7 +14,7 @@ QUnit.test('finishChains should properly copy chains from prototypes to instance
 
   var childObj = Object.create(obj);
   finishChains(childObj);
-  ok(obj['__ember_meta__'].getChains() !== childObj['__ember_meta__'].getChains(), 'The chains object is copied');
+  ok(obj['__ember_meta__'].readableChains() !== childObj['__ember_meta__'].readableChains(), 'The chains object is copied');
 });
 
 
diff --git a/packages/ember-metal/tests/watching/watch_test.js b/packages/ember-metal/tests/watching/watch_test.js
index 12caede4c19..7926003a6d8 100644
--- a/packages/ember-metal/tests/watching/watch_test.js
+++ b/packages/ember-metal/tests/watching/watch_test.js
@@ -203,7 +203,7 @@ QUnit.test('when watching a global object, destroy should remove chain watchers
   watch(obj, 'Global.foo');
 
   var meta_Global = Ember.meta(Global);
-  var chainNode = Ember.meta(obj).getChains()._chains.Global._chains.foo;
+  var chainNode = Ember.meta(obj).readableChains()._chains.Global._chains.foo;
 
   equal(meta_Global.peekWatching('foo'), 1, 'should be watching foo');
   equal(meta_Global.readableChainWatchers().has('foo', chainNode), true, 'should have chain watcher');
@@ -225,7 +225,7 @@ QUnit.test('when watching another object, destroy should remove chain watchers f
   watch(objA, 'b.foo');
 
   var meta_objB = Ember.meta(objB);
-  var chainNode = Ember.meta(objA).getChains()._chains.b._chains.foo;
+  var chainNode = Ember.meta(objA).readableChains()._chains.b._chains.foo;
 
   equal(meta_objB.peekWatching('foo'), 1, 'should be watching foo');
   equal(meta_objB.readableChainWatchers().has('foo', chainNode), true, 'should have chain watcher');

From 8886eb7f689b7415e1a89da7e1e8a925278555e2 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:31:40 -0400
Subject: [PATCH 27/39] commenting

---
 packages/ember-metal/lib/meta.js | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 64937c37762..07c263017d3 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -9,16 +9,26 @@ import isEnabled from 'ember-metal/features';
 @module ember-metal
 */
 
+/*
+ This declares the members on the Meta class. All access to Meta needs
+ to go through them.
+
+ In general, the `readable` variants will give you an object (if it
+ already exists) that you can read but should not modify. The
+ `writable` variants will give you a mutable object, and they will
+ create it if it didn't already exist.
+
+*/
 let members = {
-  cache: ownMap,
-  watching: inheritedMap,
-  mixins: inheritedMap,
-  bindings: inheritedMap,
-  values: inheritedMap,
-  listeners: inheritedMapOfLists,
-  deps: inheritedMapOfMaps,
-  chainWatchers: ownCustomObject,
-  chains: inheritedCustomObject
+  cache: ownMap,                  // writableCache, readableCache
+  watching: inheritedMap,         // writableWatching, readableWatching, peakWatching, clearWatching
+  mixins: inheritedMap,           // writableMixins, readableMixins, peakMixins, clearMixins
+  bindings: inheritedMap,         // writableBindings, readableBindings, peakBindings, clearBindings
+  values: inheritedMap,           // writableValues, readableValues, peakValues, clearValues
+  listeners: inheritedMapOfLists, // writableListeners, readableListeners, getAllListeners
+  deps: inheritedMapOfMaps,       // writableDeps, readableDeps, getAllDeps
+  chainWatchers: ownCustomObject, // writableChainWatchers, readableChainWatchers
+  chains: inheritedCustomObject   // writableChains, readableChains
 };
 
 let memberNames = Object.keys(members);

From 45d73c117273bc87813d87017b08db3e84575d4a Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Sun, 2 Aug 2015 21:32:01 -0400
Subject: [PATCH 28/39] spelling, how does it work?

---
 packages/ember-metal/lib/meta.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 07c263017d3..9ddcd09d698 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -21,10 +21,10 @@ import isEnabled from 'ember-metal/features';
 */
 let members = {
   cache: ownMap,                  // writableCache, readableCache
-  watching: inheritedMap,         // writableWatching, readableWatching, peakWatching, clearWatching
-  mixins: inheritedMap,           // writableMixins, readableMixins, peakMixins, clearMixins
-  bindings: inheritedMap,         // writableBindings, readableBindings, peakBindings, clearBindings
-  values: inheritedMap,           // writableValues, readableValues, peakValues, clearValues
+  watching: inheritedMap,         // writableWatching, readableWatching, peekWatching, clearWatching
+  mixins: inheritedMap,           // writableMixins, readableMixins, peekMixins, clearMixins
+  bindings: inheritedMap,         // writableBindings, readableBindings, peekBindings, clearBindings
+  values: inheritedMap,           // writableValues, readableValues, peekValues, clearValues
   listeners: inheritedMapOfLists, // writableListeners, readableListeners, getAllListeners
   deps: inheritedMapOfMaps,       // writableDeps, readableDeps, getAllDeps
   chainWatchers: ownCustomObject, // writableChainWatchers, readableChainWatchers

From 26008e045cc6ed24ca6150b993b4e9e20708f0db Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 02:33:21 -0400
Subject: [PATCH 29/39] starting some new meta tests

---
 .../tests/{utils => }/meta_test.js            | 33 +++++++++++++++++--
 1 file changed, 30 insertions(+), 3 deletions(-)
 rename packages/ember-metal/tests/{utils => }/meta_test.js (51%)

diff --git a/packages/ember-metal/tests/utils/meta_test.js b/packages/ember-metal/tests/meta_test.js
similarity index 51%
rename from packages/ember-metal/tests/utils/meta_test.js
rename to packages/ember-metal/tests/meta_test.js
index 49982786100..9eac8165980 100644
--- a/packages/ember-metal/tests/utils/meta_test.js
+++ b/packages/ember-metal/tests/meta_test.js
@@ -1,6 +1,6 @@
 import {
   meta
-} from 'ember-metal/utils';
+} from 'ember-metal/meta';
 
 QUnit.module('Ember.meta');
 
@@ -12,8 +12,6 @@ QUnit.test('should return the same hash for an object', function() {
   equal(meta(obj).foo, 'bar', 'returns same hash with multiple calls to Ember.meta()');
 });
 
-QUnit.module('Ember.meta enumerable');
-
 QUnit.test('meta is not enumerable', function () {
   var proto, obj, props, prop;
   proto = { foo: 'bar' };
@@ -55,3 +53,32 @@ QUnit.test('meta is not enumerable', function () {
     }
   }
 });
+
+QUnit.skip('meta.listeners basics', function(assert) {
+  let t = {};
+  let m = meta({});
+  m.addToListeners({ eventName: 'hello', target: t, method: 'm', flags: 0 });
+  let matching = m.matchingListeners(e => e.eventName === 'hello');
+  assert.equal(matching.length, 1);
+  assert.equal(matching[0].target, t);
+  m.removeFromListeners({ eventName: 'hello', target: t, method: 'm'});
+  matching = m.matchingListeners(e => e.eventName === 'hello');
+  assert.equal(matching.length, 0);
+});
+
+QUnit.skip('meta.listeners inheritance', function(assert) {
+  let target = {};
+  let parent = {};
+  let parentMeta = meta(parent);
+  parentMeta.addToListeners({ eventName: 'hello', target, method: 'm', flags: 0 });
+
+  let child = Object.create(parent);
+  let m = meta(child);
+
+  let matching = m.matchingListeners(e => e.eventName === 'hello');
+  assert.equal(matching.length, 1);
+  assert.equal(matching[0].target, target);
+  m.removeFromListeners({ eventName: 'hello', target, method: 'm'});
+  matching = m.matchingListeners(e => e.eventName === 'hello');
+  assert.equal(matching.length, 0);
+});

From c4b3bceaf6d94a73d1c251bbacc5682474ec989c Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 03:15:31 -0400
Subject: [PATCH 30/39] point everything at the new meta module

---
 packages/ember-metal/lib/alias.js             |  6 +--
 packages/ember-metal/lib/chains.js            |  2 +-
 packages/ember-metal/lib/computed.js          |  6 +--
 packages/ember-metal/lib/events.js            |  2 +-
 packages/ember-metal/lib/meta.js              | 38 ++++++++++++-------
 packages/ember-metal/lib/mixin.js             |  2 +-
 packages/ember-metal/lib/properties.js        |  2 +-
 packages/ember-metal/lib/utils.js             |  5 +--
 packages/ember-metal/lib/watch_key.js         |  2 +-
 packages/ember-metal/lib/watch_path.js        |  2 +-
 .../tests/accessors/mandatory_setters_test.js |  2 +-
 packages/ember-metal/tests/alias_test.js      |  2 +-
 packages/ember-metal/tests/events_test.js     |  2 +-
 packages/ember-metal/tests/meta_test.js       |  4 +-
 packages/ember-runtime/lib/mixins/-proxy.js   |  2 +-
 .../ember-runtime/lib/system/core_object.js   |  2 +-
 16 files changed, 43 insertions(+), 38 deletions(-)

diff --git a/packages/ember-metal/lib/alias.js b/packages/ember-metal/lib/alias.js
index 29e4240260e..78f6dcbde93 100644
--- a/packages/ember-metal/lib/alias.js
+++ b/packages/ember-metal/lib/alias.js
@@ -7,10 +7,8 @@ import {
   defineProperty
 } from 'ember-metal/properties';
 import { ComputedProperty } from 'ember-metal/computed';
-import {
-  meta,
-  inspect
-} from 'ember-metal/utils';
+import { inspect } from 'ember-metal/utils';
+import { meta } from 'ember-metal/meta';
 import {
   addDependentKeys,
   removeDependentKeys
diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index b65db575ac2..63bc024e5a9 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -1,6 +1,6 @@
 import Ember from 'ember-metal/core'; // warn, assert, etc;
 import { get, normalizeTuple } from 'ember-metal/property_get';
-import { meta as metaFor } from 'ember-metal/utils';
+import { meta as metaFor } from 'ember-metal/meta';
 import { watchKey, unwatchKey } from 'ember-metal/watch_key';
 
 var FIRST_KEY = /^([^\.]+)/;
diff --git a/packages/ember-metal/lib/computed.js b/packages/ember-metal/lib/computed.js
index 00b9b1e1944..46a5a35d564 100644
--- a/packages/ember-metal/lib/computed.js
+++ b/packages/ember-metal/lib/computed.js
@@ -1,9 +1,7 @@
 import Ember from 'ember-metal/core';
 import { set } from 'ember-metal/property_set';
-import {
-  meta,
-  inspect
-} from 'ember-metal/utils';
+import { inspect } from 'ember-metal/utils';
+import { meta } from 'ember-metal/meta';
 import expandProperties from 'ember-metal/expand_properties';
 import EmberError from 'ember-metal/error';
 import {
diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index fa9a217cc8e..353781f0cd5 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -9,10 +9,10 @@
 */
 import Ember from 'ember-metal/core';
 import {
-  meta as metaFor,
   apply,
   applyStr
 } from 'ember-metal/utils';
+import { meta as metaFor } from 'ember-metal/meta';
 
 /* listener flags */
 var ONCE = 1;
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 9ddcd09d698..9e6e2b9dacc 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -18,17 +18,29 @@ import isEnabled from 'ember-metal/features';
  `writable` variants will give you a mutable object, and they will
  create it if it didn't already exist.
 
+ The following methods will get generated metaprogrammatically, and
+ I'm including them here for greppability:
+
+ writableCache, readableCache, writableWatching, readableWatching,
+ peekWatching, clearWatching, writableMixins, readableMixins,
+ peekMixins, clearMixins, writableBindings, readableBindings,
+ peekBindings, clearBindings, writableValues, readableValues,
+ peekValues, clearValues, writableListeners, readableListeners,
+ getAllListeners, writableDeps, readableDeps, getAllDeps
+ writableChainWatchers, readableChainWatchers, writableChains,
+ readableChains
+
 */
 let members = {
-  cache: ownMap,                  // writableCache, readableCache
-  watching: inheritedMap,         // writableWatching, readableWatching, peekWatching, clearWatching
-  mixins: inheritedMap,           // writableMixins, readableMixins, peekMixins, clearMixins
-  bindings: inheritedMap,         // writableBindings, readableBindings, peekBindings, clearBindings
-  values: inheritedMap,           // writableValues, readableValues, peekValues, clearValues
-  listeners: inheritedMapOfLists, // writableListeners, readableListeners, getAllListeners
-  deps: inheritedMapOfMaps,       // writableDeps, readableDeps, getAllDeps
-  chainWatchers: ownCustomObject, // writableChainWatchers, readableChainWatchers
-  chains: inheritedCustomObject   // writableChains, readableChains
+  cache: ownMap,
+  watching: inheritedMap,
+  mixins: inheritedMap,
+  bindings: inheritedMap,
+  values: inheritedMap,
+  listeners: inheritedMapOfLists,
+  deps: inheritedMapOfMaps,
+  chainWatchers: ownCustomObject,
+  chains: inheritedCustomObject
 };
 
 let memberNames = Object.keys(members);
@@ -76,7 +88,7 @@ function ownMap(name, Meta) {
 function getOrCreateOwnMap(key) {
   let ret = this[key];
   if (!ret) {
-    ret = this[key] = Object.create(null);
+    ret = this[key] = {};
   }
   return ret;
 }
@@ -104,7 +116,7 @@ function inheritedMap(name, Meta) {
   };
 
   Meta.prototype['clear' + capitalized] = function() {
-    this[key] = Object.create(null);
+    this[key] = {};
   };
 }
 
@@ -114,7 +126,7 @@ function getOrCreateInheritedMap(key) {
     if (this.parent) {
       ret = this[key] = Object.create(getOrCreateInheritedMap.call(this.parent, key));
     } else {
-      ret = this[key] = Object.create(null);
+      ret = this[key] = {};
     }
   }
   return ret;
@@ -170,7 +182,7 @@ function inheritedMapOfMaps(name, Meta) {
     let outerMap = getOrCreateInheritedMap.call(this, key);
     let innerMap = outerMap[subkey];
     if (!innerMap) {
-      innerMap = outerMap[subkey] = Object.create(null);
+      innerMap = outerMap[subkey] = {};
     } else if (!Object.hasOwnProperty.call(outerMap, subkey)) {
       innerMap = outerMap[subkey] = Object.create(innerMap);
     }
diff --git a/packages/ember-metal/lib/mixin.js b/packages/ember-metal/lib/mixin.js
index 1b986b562b3..874b8d77a49 100644
--- a/packages/ember-metal/lib/mixin.js
+++ b/packages/ember-metal/lib/mixin.js
@@ -14,10 +14,10 @@ import { get } from 'ember-metal/property_get';
 import { set, trySet } from 'ember-metal/property_set';
 import {
   guidFor,
-  meta as metaFor,
   wrap,
   makeArray
 } from 'ember-metal/utils';
+import { meta as metaFor } from 'ember-metal/meta';
 import expandProperties from 'ember-metal/expand_properties';
 import {
   Descriptor,
diff --git a/packages/ember-metal/lib/properties.js b/packages/ember-metal/lib/properties.js
index cd7e8b14ec4..3fd5f3f705e 100644
--- a/packages/ember-metal/lib/properties.js
+++ b/packages/ember-metal/lib/properties.js
@@ -4,7 +4,7 @@
 
 import Ember from 'ember-metal/core';
 import isEnabled from 'ember-metal/features';
-import { meta as metaFor } from 'ember-metal/utils';
+import { meta as metaFor } from 'ember-metal/meta';
 import { overrideChains } from 'ember-metal/property_events';
 // ..........................................................
 // DESCRIPTOR
diff --git a/packages/ember-metal/lib/utils.js b/packages/ember-metal/lib/utils.js
index c69d844e2c3..86f6a17095c 100644
--- a/packages/ember-metal/lib/utils.js
+++ b/packages/ember-metal/lib/utils.js
@@ -3,8 +3,6 @@
 //
 'REMOVE_USE_STRICT: true';
 
-import { meta } from 'ember-metal/meta';
-
 /**
 @module ember-metal
 */
@@ -500,6 +498,5 @@ export function applyStr(t, m, a) {
 export {
   GUID_KEY,
   makeArray,
-  canInvoke,
-  meta // this is temporary until I can refactor all the import sites
+  canInvoke
 };
diff --git a/packages/ember-metal/lib/watch_key.js b/packages/ember-metal/lib/watch_key.js
index 2773a61efef..803ea869f92 100644
--- a/packages/ember-metal/lib/watch_key.js
+++ b/packages/ember-metal/lib/watch_key.js
@@ -1,7 +1,7 @@
 import isEnabled from 'ember-metal/features';
 import {
   meta as metaFor
-} from 'ember-metal/utils';
+} from 'ember-metal/meta';
 import {
   MANDATORY_SETTER_FUNCTION,
   DEFAULT_GETTER_FUNCTION
diff --git a/packages/ember-metal/lib/watch_path.js b/packages/ember-metal/lib/watch_path.js
index 53685bd18b9..d6f6d8a75f5 100644
--- a/packages/ember-metal/lib/watch_path.js
+++ b/packages/ember-metal/lib/watch_path.js
@@ -1,6 +1,6 @@
 import {
   meta as metaFor
-} from 'ember-metal/utils';
+} from 'ember-metal/meta';
 import { ChainNode } from 'ember-metal/chains';
 
 // get the chains for the current object. If the current object has
diff --git a/packages/ember-metal/tests/accessors/mandatory_setters_test.js b/packages/ember-metal/tests/accessors/mandatory_setters_test.js
index 3bafd745ae5..bf3a12e55ff 100644
--- a/packages/ember-metal/tests/accessors/mandatory_setters_test.js
+++ b/packages/ember-metal/tests/accessors/mandatory_setters_test.js
@@ -2,7 +2,7 @@ import isEnabled from 'ember-metal/features';
 import { get } from 'ember-metal/property_get';
 import { set } from 'ember-metal/property_set';
 import { watch } from 'ember-metal/watching';
-import { meta as metaFor } from 'ember-metal/utils';
+import { meta as metaFor } from 'ember-metal/meta';
 
 QUnit.module('mandatory-setters');
 
diff --git a/packages/ember-metal/tests/alias_test.js b/packages/ember-metal/tests/alias_test.js
index 546fac0c451..e432314dcc5 100644
--- a/packages/ember-metal/tests/alias_test.js
+++ b/packages/ember-metal/tests/alias_test.js
@@ -2,7 +2,7 @@ import alias from 'ember-metal/alias';
 import { defineProperty } from 'ember-metal/properties';
 import { get } from 'ember-metal/property_get';
 import { set } from 'ember-metal/property_set';
-import { meta } from 'ember-metal/utils';
+import { meta } from 'ember-metal/meta';
 import { isWatching } from 'ember-metal/watching';
 import { addObserver, removeObserver } from 'ember-metal/observer';
 
diff --git a/packages/ember-metal/tests/events_test.js b/packages/ember-metal/tests/events_test.js
index ead7da29c05..d09713b226a 100644
--- a/packages/ember-metal/tests/events_test.js
+++ b/packages/ember-metal/tests/events_test.js
@@ -1,5 +1,5 @@
 import { Mixin } from 'ember-metal/mixin';
-import { meta } from 'ember-metal/utils';
+import { meta } from 'ember-metal/meta';
 
 import {
   on,
diff --git a/packages/ember-metal/tests/meta_test.js b/packages/ember-metal/tests/meta_test.js
index 9eac8165980..721523fcee8 100644
--- a/packages/ember-metal/tests/meta_test.js
+++ b/packages/ember-metal/tests/meta_test.js
@@ -61,7 +61,7 @@ QUnit.skip('meta.listeners basics', function(assert) {
   let matching = m.matchingListeners(e => e.eventName === 'hello');
   assert.equal(matching.length, 1);
   assert.equal(matching[0].target, t);
-  m.removeFromListeners({ eventName: 'hello', target: t, method: 'm'});
+  m.removeFromListeners({ eventName: 'hello', target: t, method: 'm' });
   matching = m.matchingListeners(e => e.eventName === 'hello');
   assert.equal(matching.length, 0);
 });
@@ -78,7 +78,7 @@ QUnit.skip('meta.listeners inheritance', function(assert) {
   let matching = m.matchingListeners(e => e.eventName === 'hello');
   assert.equal(matching.length, 1);
   assert.equal(matching[0].target, target);
-  m.removeFromListeners({ eventName: 'hello', target, method: 'm'});
+  m.removeFromListeners({ eventName: 'hello', target, method: 'm' });
   matching = m.matchingListeners(e => e.eventName === 'hello');
   assert.equal(matching.length, 0);
 });
diff --git a/packages/ember-runtime/lib/mixins/-proxy.js b/packages/ember-runtime/lib/mixins/-proxy.js
index ec1e768a84d..e9c653013b2 100644
--- a/packages/ember-runtime/lib/mixins/-proxy.js
+++ b/packages/ember-runtime/lib/mixins/-proxy.js
@@ -6,7 +6,7 @@
 import Ember from 'ember-metal/core'; // Ember.assert
 import { get } from 'ember-metal/property_get';
 import { set } from 'ember-metal/property_set';
-import { meta } from 'ember-metal/utils';
+import { meta } from 'ember-metal/meta';
 import {
   addObserver,
   removeObserver,
diff --git a/packages/ember-runtime/lib/system/core_object.js b/packages/ember-runtime/lib/system/core_object.js
index 09e4c0ce43f..49c1ad72b84 100644
--- a/packages/ember-runtime/lib/system/core_object.js
+++ b/packages/ember-runtime/lib/system/core_object.js
@@ -26,9 +26,9 @@ import {
   generateGuid,
   GUID_KEY_PROPERTY,
   NEXT_SUPER_PROPERTY,
-  meta,
   makeArray
 } from 'ember-metal/utils';
+import { meta } from 'ember-metal/meta';
 import { finishChains } from 'ember-metal/chains';
 import { sendEvent } from 'ember-metal/events';
 import {

From 71ebf9cd45e18a3cc4f49bad980c735ad78becb1 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 05:38:25 -0400
Subject: [PATCH 31/39] fancy new listener data structures

---
 packages/ember-metal/lib/events.js         | 116 ++--------------
 packages/ember-metal/lib/meta.js           |  45 ++----
 packages/ember-metal/lib/meta_listeners.js | 154 +++++++++++++++++++++
 packages/ember-metal/tests/events_test.js  |   5 +-
 packages/ember-metal/tests/meta_test.js    |  42 ++++--
 5 files changed, 208 insertions(+), 154 deletions(-)
 create mode 100644 packages/ember-metal/lib/meta_listeners.js

diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index 353781f0cd5..e8f20bf56f4 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -14,9 +14,7 @@ import {
 } from 'ember-metal/utils';
 import { meta as metaFor } from 'ember-metal/meta';
 
-/* listener flags */
-var ONCE = 1;
-var SUSPENDED = 2;
+import { ONCE, SUSPENDED } from 'ember-metal/meta_listeners';
 
 
 /*
@@ -51,16 +49,10 @@ function indexOf(array, target, method) {
   return index;
 }
 
-function actionsFor(obj, eventName) {
-  return metaFor(obj, true).writableListeners(eventName);
-}
-
 export function accumulateListeners(obj, eventName, otherActions) {
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.readableListeners(eventName);
-
-  if (!actions) { return; }
-
+  if (!meta) { return; }
+  var actions = meta.matchingListeners(eventName);
   var newActions = [];
 
   for (var i = actions.length - 3; i >= 0; i -= 3) {
@@ -98,19 +90,12 @@ export function addListener(obj, eventName, target, method, once) {
     target = null;
   }
 
-  var actions = actionsFor(obj, eventName);
-  var actionIndex = indexOf(actions, target, method);
   var flags = 0;
-
   if (once) {
     flags |= ONCE;
   }
 
-  if (actionIndex !== -1) {
-    return;
-  }
-
-  actions.push(target, method, flags);
+  metaFor(obj).addToListeners(eventName, target, method, flags);
 
   if ('function' === typeof obj.didAddListener) {
     obj.didAddListener(eventName, target, method);
@@ -138,31 +123,11 @@ export function removeListener(obj, eventName, target, method) {
     target = null;
   }
 
-  function _removeListener(target, method) {
-    var actions = actionsFor(obj, eventName);
-    var actionIndex = indexOf(actions, target, method);
-
-    // action doesn't exist, give up silently
-    if (actionIndex === -1) { return; }
-
-    actions.splice(actionIndex, 3);
-
+  metaFor(obj).removeFromListeners(eventName, target, method, (...args) => {
     if ('function' === typeof obj.didRemoveListener) {
-      obj.didRemoveListener(eventName, target, method);
+      obj.didRemoveListener(...args);
     }
-  }
-
-  if (method) {
-    _removeListener(target, method);
-  } else {
-    var meta = obj['__ember_meta__'];
-    var actions = meta && meta.readableListeners(eventName);
-
-    if (!actions) { return; }
-    for (var i = actions.length - 3; i >= 0; i -= 3) {
-      _removeListener(actions[i], actions[i + 1]);
-    }
-  }
+  });
 }
 
 /**
@@ -184,25 +149,7 @@ export function removeListener(obj, eventName, target, method) {
   @param {Function} callback
 */
 export function suspendListener(obj, eventName, target, method, callback) {
-  if (!method && 'function' === typeof target) {
-    method = target;
-    target = null;
-  }
-
-  var actions = actionsFor(obj, eventName);
-  var actionIndex = indexOf(actions, target, method);
-
-  if (actionIndex !== -1) {
-    actions[actionIndex + 2] |= SUSPENDED; // mark the action as suspended
-  }
-
-  try {
-    return callback.call(target);
-  } finally {
-    if (actionIndex !== -1) {
-      actions[actionIndex + 2] &= ~SUSPENDED;
-    }
-  }
+  return suspendListeners(obj, [eventName], target, method, callback);
 }
 
 /**
@@ -223,30 +170,7 @@ export function suspendListeners(obj, eventNames, target, method, callback) {
     method = target;
     target = null;
   }
-
-  var suspendedActions = [];
-  var actionsList = [];
-
-  for (let i = 0, l = eventNames.length; i < l; i++) {
-    let eventName = eventNames[i];
-    let actions = actionsFor(obj, eventName);
-    let actionIndex = indexOf(actions, target, method);
-
-    if (actionIndex !== -1) {
-      actions[actionIndex + 2] |= SUSPENDED;
-      suspendedActions.push(actionIndex);
-      actionsList.push(actions);
-    }
-  }
-
-  try {
-    return callback.call(target);
-  } finally {
-    for (let i = 0, l = suspendedActions.length; i < l; i++) {
-      let actionIndex = suspendedActions[i];
-      actionsList[i][actionIndex + 2] &= ~SUSPENDED;
-    }
-  }
+  return metaFor(obj).suspendListeners(eventNames, target, method, callback);
 }
 
 /**
@@ -258,18 +182,7 @@ export function suspendListeners(obj, eventNames, target, method, callback) {
   @param obj
 */
 export function watchedEvents(obj) {
-  var listeners = obj['__ember_meta__'].getAllListeners();
-  var ret = [];
-
-  if (listeners) {
-    for (var eventName in listeners) {
-      if (eventName !== '__source__' &&
-          listeners[eventName]) {
-        ret.push(eventName);
-      }
-    }
-  }
-  return ret;
+  return metaFor(obj).watchedEvents();
 }
 
 /**
@@ -290,7 +203,7 @@ export function watchedEvents(obj) {
 export function sendEvent(obj, eventName, params, actions) {
   if (!actions) {
     var meta = obj['__ember_meta__'];
-    actions = meta && meta.readableListeners(eventName);
+    actions = meta && meta.matchingListeners(eventName);
   }
 
   if (!actions) { return; }
@@ -330,9 +243,8 @@ export function sendEvent(obj, eventName, params, actions) {
 */
 export function hasListeners(obj, eventName) {
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.readableListeners(eventName);
-
-  return !!(actions && actions.length);
+  if (!meta) { return false; }
+  return meta.matchingListeners(eventName).length > 0;
 }
 
 /**
@@ -345,7 +257,7 @@ export function hasListeners(obj, eventName) {
 export function listenersFor(obj, eventName) {
   var ret = [];
   var meta = obj['__ember_meta__'];
-  var actions = meta && meta.readableListeners(eventName);
+  var actions = meta && meta.matchingListeners(eventName);
 
   if (!actions) { return ret; }
 
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 9e6e2b9dacc..ca5154aa40a 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -4,14 +4,15 @@
 'REMOVE_USE_STRICT: true';
 
 import isEnabled from 'ember-metal/features';
+import { protoMethods as listenerMethods } from 'ember-metal/meta_listeners';
 
 /**
 @module ember-metal
 */
 
 /*
- This declares the members on the Meta class. All access to Meta needs
- to go through them.
+ This declares several meta-programmed members on the Meta class. Such
+ meta!
 
  In general, the `readable` variants will give you an object (if it
  already exists) that you can read but should not modify. The
@@ -25,8 +26,7 @@ import isEnabled from 'ember-metal/features';
  peekWatching, clearWatching, writableMixins, readableMixins,
  peekMixins, clearMixins, writableBindings, readableBindings,
  peekBindings, clearBindings, writableValues, readableValues,
- peekValues, clearValues, writableListeners, readableListeners,
- getAllListeners, writableDeps, readableDeps, getAllDeps
+ peekValues, clearValues, writableDeps, readableDeps, getAllDeps
  writableChainWatchers, readableChainWatchers, writableChains,
  readableChains
 
@@ -37,7 +37,6 @@ let members = {
   mixins: inheritedMap,
   bindings: inheritedMap,
   values: inheritedMap,
-  listeners: inheritedMapOfLists,
   deps: inheritedMapOfMaps,
   chainWatchers: ownCustomObject,
   chains: inheritedCustomObject
@@ -63,6 +62,12 @@ function Meta(obj, parentMeta) {
   // have detailed knowledge of how each property should really be
   // inherited, and we can optimize it much better than JS runtimes.
   this.parent = parentMeta;
+
+  this._initializeListeners();
+}
+
+for (let name in listenerMethods) {
+  Meta.prototype[name] = listenerMethods[name];
 }
 
 (function setupMembers() {
@@ -142,36 +147,6 @@ function getInherited(key) {
   }
 }
 
-// Implements a member that provides a lazily created mapping from
-// keys to lists, with inheritance at both levels.
-function inheritedMapOfLists(name, Meta) {
-  let key = memberProperty(name);
-  let capitalized = capitalize(name);
-
-  Meta.prototype['writable' + capitalized] = function(subkey) {
-    let map = getOrCreateInheritedMap.call(this, key);
-    let list = map[subkey];
-    if (!list) {
-      list = map[subkey] = [];
-    } else if (!Object.hasOwnProperty.call(map, subkey)) {
-      list = map[subkey] = list.slice();
-    }
-    return list;
-  };
-
-  Meta.prototype['readable' + capitalized] = function(subkey) {
-    let map = getInherited.call(this, key);
-    if (map) {
-      return map[subkey];
-    }
-  };
-
-  Meta.prototype['getAll' + capitalized] = function() {
-    return getInherited.call(this, key);
-  };
-}
-
-
 // Implements a member that provides a lazily created map of maps,
 // with inheritance at both levels.
 function inheritedMapOfMaps(name, Meta) {
diff --git a/packages/ember-metal/lib/meta_listeners.js b/packages/ember-metal/lib/meta_listeners.js
new file mode 100644
index 00000000000..736dda52585
--- /dev/null
+++ b/packages/ember-metal/lib/meta_listeners.js
@@ -0,0 +1,154 @@
+/*
+ When we render a rich template hierarchy, the set of events that
+ *might* happen tends to be much larger than the set of events that
+ actually happen. This implies that we should make listener creation &
+ destruction cheap, even at the cost of making event dispatch more
+ expensive.
+
+ Thus we store a new listener with a single push and no new
+ allocations, without even bothering to do deduplication -- we can
+ save that for dispatch time, if an event actually happens.
+ */
+
+/* listener flags */
+export var ONCE = 1;
+export var SUSPENDED = 2;
+
+export var protoMethods = {
+
+  addToListeners(eventName, target, method, flags) {
+    if (!this._listeners) {
+      this._listeners = [];
+    }
+    this._listeners.push(eventName, target, method, flags);
+  },
+
+  _finalizeListeners() {
+    if (this._listenersFinalized) { return; }
+    if (!this._listeners) { this._listeners = []; }
+    let pointer = this.parent;
+    while (pointer) {
+      let listeners = pointer._listeners;
+      if (listeners) {
+        this._listeners = this._listeners.concat(listeners);
+      }
+      if (pointer._listenersFinalized) { break; }
+      pointer = pointer.parent;
+    }
+    this._listenersFinalized = true;
+  },
+
+  removeFromListeners(eventName, target, method, didRemove) {
+    let pointer = this;
+    while (pointer) {
+      let listeners = pointer._listeners;
+      if (listeners) {
+        for (let index = listeners.length - 4; index >= 0; index -= 4) {
+          if (listeners[index] === eventName && (!method || (listeners[index + 1] === target && listeners[index + 2] === method))) {
+            if (pointer === this) {
+              // we are modifying our own list, so we edit directly
+              if (typeof didRemove === 'function') {
+                didRemove(eventName, target, listeners[index + 2]);
+              }
+              listeners.splice(index, 4);
+            } else {
+              // we are trying to remove an inherited listener, so we do
+              // just-in-time copying to detach our own listeners from
+              // our inheritance chain.
+              this._finalizeListeners();
+              return this.removeFromListeners(eventName, target, method);
+            }
+          }
+        }
+      }
+      if (pointer._listenersFinalized) { break; }
+      pointer = pointer.parent;
+    }
+  },
+
+  matchingListeners(eventName) {
+    let pointer = this;
+    let result = [];
+    while (pointer) {
+      let listeners = pointer._listeners;
+      if (listeners) {
+        for (let index = 0; index < listeners.length - 3; index += 4) {
+          if (listeners[index] === eventName) {
+            pushUniqueListener(result, listeners, index);
+          }
+        }
+      }
+      if (pointer._listenersFinalized) { break; }
+      pointer = pointer.parent;
+    }
+    let sus = this._suspendedListeners;
+    if (sus) {
+      for (let susIndex = 0; susIndex < sus.length - 2; susIndex += 3) {
+        if (eventName === sus[susIndex]) {
+          for (let resultIndex = 0; resultIndex < result.length - 2; resultIndex += 3) {
+            if (result[resultIndex] === sus[susIndex + 1] && result[resultIndex + 1] === sus[susIndex + 2]) {
+              result[resultIndex + 2] |= SUSPENDED;
+            }
+          }
+        }
+      }
+    }
+    return result;
+  },
+
+  suspendListeners(eventNames, target, method, callback) {
+    let sus = this._suspendedListeners;
+    if (!sus) {
+      sus = this._suspendedListeners = [];
+    }
+    for (let i = 0; i < eventNames.length; i++) {
+      sus.push(eventNames[i], target, method);
+    }
+    try {
+      return callback.call(target);
+    } finally {
+      if (sus.length === eventNames.length) {
+        this._suspendedListeners = undefined;
+      } else {
+        for (let i = sus.length - 3; i >= 0; i -= 3) {
+          if (sus[i + 1] === target && sus[i + 2] === method && eventNames.indexOf(sus[i]) !== -1) {
+            sus.splice(i, 3);
+          }
+        }
+      }
+    }
+  },
+
+  watchedEvents() {
+    let pointer = this;
+    let names = {};
+    while (pointer) {
+      let listeners = pointer._listeners;
+      if (listeners) {
+        for (let index = 0; index < listeners.length - 3; index += 4) {
+          names[listeners[index]] = true;
+        }
+      }
+      if (pointer._listenersFinalized) { break; }
+      pointer = pointer.parent;
+    }
+    return Object.keys(names);
+  },
+
+  _initializeListeners() {
+    this._listeners = undefined;
+    this._listenersFinalized = undefined;
+    this._suspendedListeners = undefined;
+  }
+};
+
+function pushUniqueListener(destination, source, index) {
+  let target = source[index + 1];
+  let method = source[index + 2];
+  for (let destinationIndex = 0; destinationIndex < destination.length - 2; destinationIndex += 3) {
+    if (destination[destinationIndex] === target  && destination[destinationIndex + 1] === method) {
+      return;
+    }
+  }
+  destination.push(target, method, source[index + 3]);
+}
diff --git a/packages/ember-metal/tests/events_test.js b/packages/ember-metal/tests/events_test.js
index d09713b226a..68e507b8ffc 100644
--- a/packages/ember-metal/tests/events_test.js
+++ b/packages/ember-metal/tests/events_test.js
@@ -179,7 +179,6 @@ QUnit.test('calling removeListener without method should remove all listeners',
   addListener(obj, 'event!', F2);
 
   equal(hasListeners(obj, 'event!'), true, 'has listeners');
-
   removeListener(obj, 'event!');
 
   equal(hasListeners(obj, 'event!'), false, 'has no more listeners');
@@ -205,7 +204,7 @@ QUnit.test('while suspended, it should not be possible to add a duplicate listen
   suspendListener(obj, 'event!', target, target.method, callback);
 
   equal(target.count, 1, 'should invoke');
-  equal(meta(obj).readableListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
+  equal(meta(obj).matchingListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
 
   // now test suspendListeners...
 
@@ -214,7 +213,7 @@ QUnit.test('while suspended, it should not be possible to add a duplicate listen
   suspendListeners(obj, ['event!'], target, target.method, callback);
 
   equal(target.count, 2, 'should have invoked again');
-  equal(meta(obj).readableListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
+  equal(meta(obj).matchingListeners('event!').length, 3, 'a duplicate listener wasn\'t added');
 });
 
 QUnit.test('a listener can be added as part of a mixin', function() {
diff --git a/packages/ember-metal/tests/meta_test.js b/packages/ember-metal/tests/meta_test.js
index 721523fcee8..125b30f4ef6 100644
--- a/packages/ember-metal/tests/meta_test.js
+++ b/packages/ember-metal/tests/meta_test.js
@@ -54,31 +54,45 @@ QUnit.test('meta is not enumerable', function () {
   }
 });
 
-QUnit.skip('meta.listeners basics', function(assert) {
+QUnit.test('meta.listeners basics', function(assert) {
   let t = {};
   let m = meta({});
-  m.addToListeners({ eventName: 'hello', target: t, method: 'm', flags: 0 });
-  let matching = m.matchingListeners(e => e.eventName === 'hello');
-  assert.equal(matching.length, 1);
-  assert.equal(matching[0].target, t);
-  m.removeFromListeners({ eventName: 'hello', target: t, method: 'm' });
-  matching = m.matchingListeners(e => e.eventName === 'hello');
+  m.addToListeners('hello', t, 'm', 0);
+  let matching = m.matchingListeners('hello');
+  assert.equal(matching.length, 3);
+  assert.equal(matching[0], t);
+  m.removeFromListeners('hello', t, 'm');
+  matching = m.matchingListeners('hello');
   assert.equal(matching.length, 0);
 });
 
-QUnit.skip('meta.listeners inheritance', function(assert) {
+QUnit.test('meta.listeners inheritance', function(assert) {
   let target = {};
   let parent = {};
   let parentMeta = meta(parent);
-  parentMeta.addToListeners({ eventName: 'hello', target, method: 'm', flags: 0 });
+  parentMeta.addToListeners('hello', target, 'm', 0);
 
   let child = Object.create(parent);
   let m = meta(child);
 
-  let matching = m.matchingListeners(e => e.eventName === 'hello');
-  assert.equal(matching.length, 1);
-  assert.equal(matching[0].target, target);
-  m.removeFromListeners({ eventName: 'hello', target, method: 'm' });
-  matching = m.matchingListeners(e => e.eventName === 'hello');
+  let matching = m.matchingListeners('hello');
+  assert.equal(matching.length, 3);
+  assert.equal(matching[0], target);
+  assert.equal(matching[1], 'm');
+  assert.equal(matching[2], 0);
+  m.removeFromListeners('hello', target, 'm');
+  matching = m.matchingListeners('hello');
   assert.equal(matching.length, 0);
+  matching = parentMeta.matchingListeners('hello');
+  assert.equal(matching.length, 3);
+});
+
+QUnit.test('meta.listeners deduplication', function(assert) {
+  let t = {};
+  let m = meta({});
+  m.addToListeners('hello', t, 'm', 0);
+  m.addToListeners('hello', t, 'm', 0);
+  let matching = m.matchingListeners('hello');
+  assert.equal(matching.length, 3);
+  assert.equal(matching[0], t);
 });

From 84a0a50b618da480588cf0c9e60e0fcd9785fdc3 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 06:36:28 -0400
Subject: [PATCH 32/39] remove outdated comment

---
 packages/ember-metal/lib/meta.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index ca5154aa40a..1c1194e1c28 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -99,8 +99,7 @@ function getOrCreateOwnMap(key) {
 }
 
 // Implements a member that is a lazily created POJO with inheritable
-// values. For member `thing` you get methods `getThing`,
-// `getOrCreateThing`, and `peekThing`.
+// values.
 function inheritedMap(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);

From 7b5fcc01b3da387eea48166e91f22da28a56fef9 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 12:56:06 -0400
Subject: [PATCH 33/39] micro-optimize every Object.create(null) to our own
 EmptyObject

---
 .../lib/system/application.js                 |  5 +++--
 packages/ember-htmlbars/lib/helpers.js        |  3 ++-
 packages/ember-metal/lib/chains.js            |  3 ++-
 packages/ember-metal/lib/empty_object.js      | 19 +++++++++++++++++++
 packages/ember-metal/lib/map.js               | 11 ++++++-----
 packages/ember-metal/lib/mixin.js             |  3 ++-
 packages/ember-metal/lib/streams/stream.js    |  5 +++--
 .../lib/keywords/render.js                    |  3 ++-
 packages/ember-routing/lib/system/router.js   |  9 +++++----
 packages/ember-views/lib/views/text_field.js  |  3 ++-
 10 files changed, 46 insertions(+), 18 deletions(-)
 create mode 100644 packages/ember-metal/lib/empty_object.js

diff --git a/packages/ember-application/lib/system/application.js b/packages/ember-application/lib/system/application.js
index d7b61617071..0c0bf785ec7 100644
--- a/packages/ember-application/lib/system/application.js
+++ b/packages/ember-application/lib/system/application.js
@@ -9,6 +9,7 @@ import Ember from 'ember-metal'; // Ember.deprecate, Ember.assert, Ember.librari
 import isEnabled from 'ember-metal/features';
 import { get } from 'ember-metal/property_get';
 import { set } from 'ember-metal/property_set';
+import EmptyObject from 'ember-metal/empty_object';
 import { runLoadHooks } from 'ember-runtime/system/lazy_load';
 import Namespace from 'ember-runtime/system/namespace';
 import DefaultResolver from 'ember-application/system/resolver';
@@ -722,8 +723,8 @@ if (isEnabled('ember-application-visit')) {
 }
 
 Application.reopenClass({
-  initializers: Object.create(null),
-  instanceInitializers: Object.create(null),
+  initializers: new EmptyObject(),
+  instanceInitializers: new EmptyObject(),
 
   /**
     Initializer receives an object which has the following attributes:
diff --git a/packages/ember-htmlbars/lib/helpers.js b/packages/ember-htmlbars/lib/helpers.js
index 8016f423ca2..b89ed29a085 100644
--- a/packages/ember-htmlbars/lib/helpers.js
+++ b/packages/ember-htmlbars/lib/helpers.js
@@ -8,8 +8,9 @@
  @property helpers
 */
 import Ember from 'ember-metal/core';
+import EmptyObject from 'ember-metal/empty_object';
 
-var helpers = Object.create(null);
+var helpers = new EmptyObject();
 
 /**
 @module ember
diff --git a/packages/ember-metal/lib/chains.js b/packages/ember-metal/lib/chains.js
index 63bc024e5a9..0111e832ead 100644
--- a/packages/ember-metal/lib/chains.js
+++ b/packages/ember-metal/lib/chains.js
@@ -2,6 +2,7 @@ import Ember from 'ember-metal/core'; // warn, assert, etc;
 import { get, normalizeTuple } from 'ember-metal/property_get';
 import { meta as metaFor } from 'ember-metal/meta';
 import { watchKey, unwatchKey } from 'ember-metal/watch_key';
+import EmptyObject from 'ember-metal/empty_object';
 
 var FIRST_KEY = /^([^\.]+)/;
 
@@ -19,7 +20,7 @@ function isVolatile(obj) {
 
 function Chains() { }
 
-Chains.prototype = Object.create(null);
+Chains.prototype = new EmptyObject();
 
 function ChainWatchers(obj) {
   // this obj would be the referencing chain node's parent node's value
diff --git a/packages/ember-metal/lib/empty_object.js b/packages/ember-metal/lib/empty_object.js
new file mode 100644
index 00000000000..dbe6d6ddb35
--- /dev/null
+++ b/packages/ember-metal/lib/empty_object.js
@@ -0,0 +1,19 @@
+// This exists because `Object.create(null)` is absurdly slow compared
+// to `new EmptyObject()`. In either case, you want a null prototype
+// when you're treating the object instances as arbitrary dictionaries
+// and don't want your keys colliding with build-in methods on the
+// default object prototype.
+
+var proto = Object.create(null, {
+  // without this, we will always still end up with (new
+  // EmptyObject()).constructor === Object
+  constructor: {
+    value: undefined,
+    enumerable: false,
+    writable: true
+  }
+});
+
+function EmptyObject() {}
+EmptyObject.prototype = proto;
+export default EmptyObject;
diff --git a/packages/ember-metal/lib/map.js b/packages/ember-metal/lib/map.js
index df8f54c2799..740983d2a36 100644
--- a/packages/ember-metal/lib/map.js
+++ b/packages/ember-metal/lib/map.js
@@ -23,6 +23,7 @@
 
 import Ember from 'ember-metal/core';
 import { guidFor } from 'ember-metal/utils';
+import EmptyObject from 'ember-metal/empty_object';
 
 function missingFunction(fn) {
   throw new TypeError(`${Object.prototype.toString.call(fn)} is not a function`);
@@ -33,10 +34,10 @@ function missingNew(name) {
 }
 
 function copyNull(obj) {
-  var output = Object.create(null);
+  var output = new EmptyObject();
 
   for (var prop in obj) {
-    // hasOwnPropery is not needed because obj is Object.create(null);
+    // hasOwnPropery is not needed because obj is new EmptyObject();
     output[prop] = obj[prop];
   }
 
@@ -92,7 +93,7 @@ OrderedSet.prototype = {
     @private
   */
   clear() {
-    this.presenceSet = Object.create(null);
+    this.presenceSet = new EmptyObject();
     this.list = [];
     this.size = 0;
   },
@@ -246,7 +247,7 @@ function Map() {
   if (this instanceof this.constructor) {
     this._keys = OrderedSet.create();
     this._keys._silenceRemoveDeprecation = true;
-    this._values = Object.create(null);
+    this._values = new EmptyObject();
     this.size = 0;
   } else {
     missingNew('OrderedSet');
@@ -405,7 +406,7 @@ Map.prototype = {
   */
   clear() {
     this._keys.clear();
-    this._values = Object.create(null);
+    this._values = new EmptyObject();
     this.size = 0;
   },
 
diff --git a/packages/ember-metal/lib/mixin.js b/packages/ember-metal/lib/mixin.js
index 874b8d77a49..bafe40de2cd 100644
--- a/packages/ember-metal/lib/mixin.js
+++ b/packages/ember-metal/lib/mixin.js
@@ -10,6 +10,7 @@
 
 import Ember from 'ember-metal/core'; // warn, assert, wrap, et;
 import merge from 'ember-metal/merge';
+import EmptyObject from 'ember-metal/empty_object';
 import { get } from 'ember-metal/property_get';
 import { set, trySet } from 'ember-metal/property_set';
 import {
@@ -332,7 +333,7 @@ function connectStreamBinding(obj, key, stream) {
   stream.subscribe(onNotify);
 
   if (obj._streamBindingSubscriptions === undefined) {
-    obj._streamBindingSubscriptions = Object.create(null);
+    obj._streamBindingSubscriptions = new EmptyObject();
   }
 
   obj._streamBindingSubscriptions[key] = onNotify;
diff --git a/packages/ember-metal/lib/streams/stream.js b/packages/ember-metal/lib/streams/stream.js
index 372a31b0e47..57ee12656ef 100644
--- a/packages/ember-metal/lib/streams/stream.js
+++ b/packages/ember-metal/lib/streams/stream.js
@@ -2,6 +2,7 @@ import Ember from 'ember-metal/core';
 import { getFirstKey, getTailPath } from 'ember-metal/path_cache';
 import { addObserver, removeObserver } from 'ember-metal/observer';
 import { isStream } from 'ember-metal/streams/utils';
+import EmptyObject from 'ember-metal/empty_object';
 import Subscriber from 'ember-metal/streams/subscriber';
 import Dependency from 'ember-metal/streams/dependency';
 
@@ -51,7 +52,7 @@ Stream.prototype = {
 
   getKey(key) {
     if (this.children === undefined) {
-      this.children = Object.create(null);
+      this.children = new EmptyObject();
     }
 
     var keyStream = this.children[key];
@@ -69,7 +70,7 @@ Stream.prototype = {
     var tailPath = getTailPath(path);
 
     if (this.children === undefined) {
-      this.children = Object.create(null);
+      this.children = new EmptyObject();
     }
 
     var keyStream = this.children[firstKey];
diff --git a/packages/ember-routing-htmlbars/lib/keywords/render.js b/packages/ember-routing-htmlbars/lib/keywords/render.js
index c08a00bcd57..142d38ae5d6 100644
--- a/packages/ember-routing-htmlbars/lib/keywords/render.js
+++ b/packages/ember-routing-htmlbars/lib/keywords/render.js
@@ -1,5 +1,6 @@
 import Ember from 'ember-metal/core'; // assert
 import { get } from 'ember-metal/property_get';
+import EmptyObject from 'ember-metal/empty_object';
 import EmberError from 'ember-metal/error';
 import { isStream, read } from 'ember-metal/streams/utils';
 import { camelize } from 'ember-runtime/system/string';
@@ -186,7 +187,7 @@ function childOutletState(name, env) {
   if (!selectedOutletState) { return; }
   var matched = selectedOutletState.outlets[name];
   if (matched) {
-    var childState = Object.create(null);
+    var childState = new EmptyObject();
     childState[matched.render.outlet] = matched;
     matched.wasUsed = true;
     return childState;
diff --git a/packages/ember-routing/lib/system/router.js b/packages/ember-routing/lib/system/router.js
index 0d23bc58197..58f6175568c 100644
--- a/packages/ember-routing/lib/system/router.js
+++ b/packages/ember-routing/lib/system/router.js
@@ -4,6 +4,7 @@ import EmberError from 'ember-metal/error';
 import { get } from 'ember-metal/property_get';
 import { set } from 'ember-metal/property_set';
 import { defineProperty } from 'ember-metal/properties';
+import EmptyObject from 'ember-metal/empty_object';
 import { computed } from 'ember-metal/computed';
 import merge from 'ember-metal/merge';
 import run from 'ember-metal/run_loop';
@@ -102,7 +103,7 @@ var EmberRouter = EmberObject.extend(Evented, {
 
   init() {
     this._activeViews = {};
-    this._qpCache = Object.create(null);
+    this._qpCache = new EmptyObject();
     this._resetQueuedQueryParameterChanges();
   },
 
@@ -464,7 +465,7 @@ var EmberRouter = EmberObject.extend(Evented, {
   },
 
   _getHandlerFunction() {
-    var seen = Object.create(null);
+    var seen = new EmptyObject();
     var container = this.container;
     var DefaultRoute = container.lookupFactory('route:basic');
 
@@ -1054,7 +1055,7 @@ function appendLiveRoute(liveRoutes, defaultParentState, renderOptions) {
   var target;
   var myState = {
     render: renderOptions,
-    outlets: Object.create(null)
+    outlets: new EmptyObject()
   };
   if (renderOptions.into) {
     target = findLiveRoute(liveRoutes, renderOptions.into);
@@ -1088,7 +1089,7 @@ function appendOrphan(liveRoutes, into, myState) {
       render: {
         name: '__ember_orphans__'
       },
-      outlets: Object.create(null)
+      outlets: new EmptyObject()
     };
   }
   liveRoutes.outlets.__ember_orphans__.outlets[into] = myState;
diff --git a/packages/ember-views/lib/views/text_field.js b/packages/ember-views/lib/views/text_field.js
index 1a403ac72eb..0fc539b6827 100644
--- a/packages/ember-views/lib/views/text_field.js
+++ b/packages/ember-views/lib/views/text_field.js
@@ -6,9 +6,10 @@ import { computed } from 'ember-metal/computed';
 import environment from 'ember-metal/environment';
 import Component from 'ember-views/views/component';
 import TextSupport from 'ember-views/mixins/text_support';
+import EmptyObject from 'ember-metal/empty_object';
 
 var inputTypeTestElement;
-var inputTypes = Object.create(null);
+var inputTypes = new EmptyObject();
 function canSetTypeOfInput(type) {
   if (type in inputTypes) {
     return inputTypes[type];

From c64b3166dc1d2855266ec2b86a03ec2d786398f1 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 17:41:16 -0400
Subject: [PATCH 34/39] fix silly unnecessary defProp

---
 packages/ember-metal/lib/meta.js | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 1c1194e1c28..95781771a51 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -268,10 +268,8 @@ export function meta(obj, writable) {
     return ret || EMPTY_META;
   }
 
-  if (obj.__defineNonEnumerable) {
-    obj.__defineNonEnumerable(EMBER_META_PROPERTY);
-  } else {
-    Object.defineProperty(obj, '__ember_meta__', META_DESC);
+  if (ret && ret.source === obj) {
+    return ret;
   }
 
   if (!ret) {
@@ -279,9 +277,16 @@ export function meta(obj, writable) {
     if (isEnabled('mandatory-setter')) {
       ret.writableValues();
     }
-  } else if (ret.source !== obj) {
+  } else {
     ret = new Meta(obj, ret);
   }
+
+  if (obj.__defineNonEnumerable) {
+    obj.__defineNonEnumerable(EMBER_META_PROPERTY);
+  } else {
+    Object.defineProperty(obj, '__ember_meta__', META_DESC);
+  }
   obj.__ember_meta__ = ret;
+
   return ret;
 }

From 09218cf889c964b36c46bfaf37f52a1032dcdced Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 20:24:21 -0400
Subject: [PATCH 35/39] incorporating stef feedback

---
 packages/ember-metal/lib/meta.js | 51 +++++++++++++-------------------
 1 file changed, 21 insertions(+), 30 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 95781771a51..c0b357554ed 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -43,12 +43,11 @@ let members = {
 };
 
 let memberNames = Object.keys(members);
+let memberProperties = memberNames.map(memberProperty);
 
 function Meta(obj, parentMeta) {
   // preallocate a slot for each member
-  for (let i = 0; i < memberNames.length; i++) {
-    this[memberProperty(memberNames[i])] = undefined;
-  }
+  memberProperties.forEach(prop => this[prop] = undefined);
 
   // used only internally
   this.source = obj;
@@ -69,15 +68,7 @@ function Meta(obj, parentMeta) {
 for (let name in listenerMethods) {
   Meta.prototype[name] = listenerMethods[name];
 }
-
-(function setupMembers() {
-  for (let i = 0; i < memberNames.length; i++) {
-    let name = memberNames[i];
-    let implementation = members[name];
-    implementation(name, Meta);
-  }
-})();
-
+memberNames.forEach(name => members[name](name, Meta));
 
 // Implements a member that is a lazily created, non-inheritable
 // POJO.
@@ -85,18 +76,18 @@ function ownMap(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
   Meta.prototype['writable' + capitalized] = function() {
-    return getOrCreateOwnMap.call(this, key);
+    return this._getOrCreateOwnMap(key);
   };
   Meta.prototype['readable' + capitalized] = function() { return this[key]; };
 }
 
-function getOrCreateOwnMap(key) {
+Meta.prototype._getOrCreateOwnMap = function(key) {
   let ret = this[key];
   if (!ret) {
     ret = this[key] = {};
   }
   return ret;
-}
+};
 
 // Implements a member that is a lazily created POJO with inheritable
 // values.
@@ -105,15 +96,15 @@ function inheritedMap(name, Meta) {
   let capitalized = capitalize(name);
 
   Meta.prototype['writable' + capitalized] = function() {
-    return getOrCreateInheritedMap.call(this, key);
+    return this._getOrCreateInheritedMap(key);
   };
 
   Meta.prototype['readable' + capitalized] = function() {
-    return getInherited.call(this, key);
+    return this._getInherited(key);
   };
 
   Meta.prototype['peek' + capitalized] = function(subkey) {
-    let map = getInherited.call(this, key);
+    let map = this._getInherited(key);
     if (map) {
       return map[subkey];
     }
@@ -124,27 +115,27 @@ function inheritedMap(name, Meta) {
   };
 }
 
-function getOrCreateInheritedMap(key) {
+Meta.prototype._getOrCreateInheritedMap = function(key) {
   let ret = this[key];
   if (!ret) {
     if (this.parent) {
-      ret = this[key] = Object.create(getOrCreateInheritedMap.call(this.parent, key));
+      ret = this[key] = Object.create(this.parent._getOrCreateInheritedMap(key));
     } else {
       ret = this[key] = {};
     }
   }
   return ret;
-}
+};
 
-function getInherited(key) {
+Meta.prototype._getInherited = function(key) {
   let pointer = this;
-  while (pointer) {
+  while (pointer !== undefined) {
     if (pointer[key]) {
       return pointer[key];
     }
     pointer = pointer.parent;
   }
-}
+};
 
 // Implements a member that provides a lazily created map of maps,
 // with inheritance at both levels.
@@ -153,7 +144,7 @@ function inheritedMapOfMaps(name, Meta) {
   let capitalized = capitalize(name);
 
   Meta.prototype['writable' + capitalized] = function(subkey) {
-    let outerMap = getOrCreateInheritedMap.call(this, key);
+    let outerMap = this._getOrCreateInheritedMap(key);
     let innerMap = outerMap[subkey];
     if (!innerMap) {
       innerMap = outerMap[subkey] = {};
@@ -164,14 +155,14 @@ function inheritedMapOfMaps(name, Meta) {
   };
 
   Meta.prototype['readable' + capitalized] = function(subkey) {
-    let map = getInherited.call(this, key);
+    let map = this._getInherited(key);
     if (map) {
       return map[subkey];
     }
   };
 
   Meta.prototype['getAll' + capitalized] = function() {
-    return getInherited.call(this, key);
+    return this._getInherited(key);
   };
 }
 
@@ -198,11 +189,11 @@ function ownCustomObject(name, Meta) {
 function inheritedCustomObject(name, Meta) {
   let key = memberProperty(name);
   let capitalized = capitalize(name);
-  let writable = Meta.prototype['writable' + capitalized] = function(create) {
+  Meta.prototype['writable' + capitalized] = function(create) {
     let ret = this[key];
     if (!ret) {
       if (this.parent) {
-        ret = this[key] = writable.call(this.parent, create).copy(this.source);
+        ret = this[key] = this.parent['writable' + capitalized](create).copy(this.source);
       } else {
         ret = this[key] = create(this.source);
       }
@@ -210,7 +201,7 @@ function inheritedCustomObject(name, Meta) {
     return ret;
   };
   Meta.prototype['readable' + capitalized] = function() {
-    return getInherited.call(this, key);
+    return this._getInherited(key);
   };
 }
 

From 714f0b8b7d4c95d18b561845493cc031d182eec7 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Mon, 3 Aug 2015 21:53:18 -0400
Subject: [PATCH 36/39] use empty object

---
 packages/ember-metal/lib/meta.js | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index c0b357554ed..44e00bbd5df 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -5,6 +5,7 @@
 
 import isEnabled from 'ember-metal/features';
 import { protoMethods as listenerMethods } from 'ember-metal/meta_listeners';
+import EmptyObject from 'ember-metal/empty_object';
 
 /**
 @module ember-metal
@@ -84,7 +85,7 @@ function ownMap(name, Meta) {
 Meta.prototype._getOrCreateOwnMap = function(key) {
   let ret = this[key];
   if (!ret) {
-    ret = this[key] = {};
+    ret = this[key] = new EmptyObject();
   }
   return ret;
 };
@@ -111,7 +112,7 @@ function inheritedMap(name, Meta) {
   };
 
   Meta.prototype['clear' + capitalized] = function() {
-    this[key] = {};
+    this[key] = new EmptyObject();
   };
 }
 
@@ -121,7 +122,7 @@ Meta.prototype._getOrCreateInheritedMap = function(key) {
     if (this.parent) {
       ret = this[key] = Object.create(this.parent._getOrCreateInheritedMap(key));
     } else {
-      ret = this[key] = {};
+      ret = this[key] = new EmptyObject();
     }
   }
   return ret;
@@ -147,7 +148,7 @@ function inheritedMapOfMaps(name, Meta) {
     let outerMap = this._getOrCreateInheritedMap(key);
     let innerMap = outerMap[subkey];
     if (!innerMap) {
-      innerMap = outerMap[subkey] = {};
+      innerMap = outerMap[subkey] = new EmptyObject();
     } else if (!Object.hasOwnProperty.call(outerMap, subkey)) {
       innerMap = outerMap[subkey] = Object.create(innerMap);
     }

From 580a40a75f8553bd4581f3b15ba1958c09eb3543 Mon Sep 17 00:00:00 2001
From: Stefan Penner <stefan.penner@gmail.com>
Date: Tue, 4 Aug 2015 14:34:43 -0700
Subject: [PATCH 37/39] speed up Meta instantiation

6ms -> noise

turns out there is no 0 cost abstraction in JS yet...
---
 packages/ember-metal/lib/meta.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 44e00bbd5df..1c7a395ebdb 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -44,12 +44,16 @@ let members = {
 };
 
 let memberNames = Object.keys(members);
-let memberProperties = memberNames.map(memberProperty);
 
 function Meta(obj, parentMeta) {
-  // preallocate a slot for each member
-  memberProperties.forEach(prop => this[prop] = undefined);
-
+  this.cache = undefined;
+  this.watching = undefined;
+  this.mixins = undefined;
+  this.bindings = undefined;
+  this.values = undefined;
+  this.deps = undefined;
+  this.chainWatchers = undefined;
+  this.chains = undefined;
   // used only internally
   this.source = obj;
 

From a64e21130631d3314d303545c8fa1435f582632f Mon Sep 17 00:00:00 2001
From: Stefan Penner <stefan.penner@gmail.com>
Date: Tue, 4 Aug 2015 16:34:03 -0700
Subject: [PATCH 38/39] =?UTF-8?q?don=E2=80=99t=20event=20try=20the=20for?=
 =?UTF-8?q?=20loop=20if=20there=20are=20no=20actions?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 packages/ember-metal/lib/events.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index e8f20bf56f4..6f609b9bb39 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -206,7 +206,7 @@ export function sendEvent(obj, eventName, params, actions) {
     actions = meta && meta.matchingListeners(eventName);
   }
 
-  if (!actions) { return; }
+  if (!actions || actions.length === 0) { return; }
 
   for (var i = actions.length - 3; i >= 0; i -= 3) { // looping in reverse for once listeners
     var target = actions[i];

From b6b0739ff8fd3c7df9c7c6ca3a0565ef7b5486c2 Mon Sep 17 00:00:00 2001
From: Stefan Penner <stefan.penner@gmail.com>
Date: Tue, 4 Aug 2015 16:46:57 -0700
Subject: [PATCH 39/39] remove get for an internal property that will never be
 a CP

In one example this removes nearly 8% of gets
---
 packages/ember-views/lib/views/component.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/ember-views/lib/views/component.js b/packages/ember-views/lib/views/component.js
index 7cf2539b34a..5767947860f 100644
--- a/packages/ember-views/lib/views/component.js
+++ b/packages/ember-views/lib/views/component.js
@@ -171,7 +171,7 @@ var Component = View.extend(TargetActionSupport, ComponentTemplateDeprecation, {
 
   _template: computed('templateName', {
     get() {
-      if (get(this, '_deprecatedFlagForBlockProvided')) {
+      if (this._deprecatedFlagForBlockProvided) {
         return true;
       }
       var templateName = get(this, 'templateName');