Base Change History

===================

3.10.3

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* No changes.

3.10.2

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* No changes.

3.10.1

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* No changes.

3.10.0

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* Significant performance improvements in common Base/BaseCore operations.

  For example, on Chrome:

    `new BaseCore()` is 3 times faster

    `BaseCore set()` is 3 times faster

    `BaseCore get()` is 5 times faster

  In addition to the above basic `BaseCore` numbers, improvements in CustomEvent

  performance, result in the following improvements for `Base`

    `new Base()` is 4 times faster

    `Base set()` is 4 times faster

    `Base get()` is 5 times faster

  Major performance related changes are listed in the list of updates below.

  Commit messages have detailed descriptions of incremental changes, and the

  benefits introduced.

* [!] The result of static `ATTRS` aggregation is now cached during the creation of

  the first instance of a given "class", and the cached results are reused for

  subsequent instances.

  This provides significant performance benefits, but has the potential to introduce

  a backwards compatibility issue in the hopefully rare circumstance that you're

  modifying the static ATTRS collection directly, after the first instance is created.

  [!] If you are modifying static `ATTRS` collection directly after an instance is

  created (e.g. if an optional module comes in and updates the collection dynamically),

  you will need to change the implementation to use the static `Y.Base.modifyAttrs()`

  or `Y.BaseCore.modifyAttrs()` method, so we can mark the cached aggregation 

  dirty, and recompute it.

      `Y.Base.modifyAttrs(MyClass, {..changes to merge..})`

  `Base.create` and `Base.mix` will take care of this internally, so you only need 

  to use the above methods if your own code is touching the ATTRS object on a class.

  Additionaly, `Base.create` and `Base.mix` will add the `modifyAttrs` to your created

  class, so you can also call it directly on the class. e.g. 

      `MyCreatedClass.modifyAttrs({..changes to merge..})`

3.9.1

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* No changes.

3.9.0

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* No changes.

3.8.1

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* No changes.

3.8.0

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* `Y.Base.create()` can now be used with `Y.BaseCore`, in addition to its

  existing usage with `Y.Base`. This allows non-observable, BaseCore hierarchies

  to use class extensions.

* Extracted the `Y.BaseObservable` class extension from `Y.Base`. This is a new

  class extension for `Y.BaseCore` which adds support for observability. This

  allows BaseCore subclasses to mix-in BaseObservable at runtime, bringing their

  functionality up to that of `Y.Base`.

3.7.3

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* No changes.

3.7.2

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* No changes.

3.7.1

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* No changes.

3.7.0

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* No changes.

3.6.0

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  * "value" defined in a subclass ATTRS definition, will now override

    "valueFn" for the same attribute from the superclass chain.

    Previously, "value" would only override "value" and "valueFn"

    would only overide "valueFn", and in the aggregated set of

    attributes, "valueFn" would take precedence over "value".

    This meant that subclasses had to define a "valueFn" to overide

    superclasses, if the superclass used "valueFn".

3.5.1

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  * No changes.

3.5.0

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  * Only invoke Base constructor logic once to

    support multi-inheritance scenario in which

    an extension passed to Base.create inherits from Base

    itself.

    NOTE: To support multiple inhertiance more deeply, we'd

    need to remove the hasOwnProperty restriction around object

    key iteration.

  * Added Y.BaseCore which is core Base functionality without

    Custom Events (it uses Y.AttributeCore instead of Y.Attribute).

    Y.BaseCore still maintains the ATTRS handling, init/destroy

    lifecycle and plugin support, but doesn't fire any custom evnets

    of it's own (the idea is that it will the base for Node-Plugin

    type components, built off of a WidgetCore)

    Y.Base is now Y.BaseCore + Y.Attribute, and is 100% backwards

    compatible.

    Summary:

    Y.Attribute     - Common Attribute Functionality (100% backwards compat)

    Y.Base          - Common Base Functionality (100% backwards compat)

    Y.AttributeCore - Lightest Attribute support, without CustomEvents

    Y.BaseCore      - Lightest Base support, without CustomEvents

    --

    Y.AttributeEvents - Augmentable Attribute Events support

    Y.AttributeExtras - Augmentable 20% usage for Attribute (modifyAttr, removeAttr, reset ...)

    Y.AttributeComplex - Augmentable support for constructor complex attribute parsing ({"x.y":foo})

    --

    Y.Attribute = Y.AttributeCore + Y.AttributeEvents + Y.AttributeExtras

    Y.Base      = Y.BaseCore + Y.Attribute

    --

    Modules:

    "base-base" : Y.Base

    "base-core" : Y.BaseCore

    "base-build" : Y.Base.build/create/mix mixin

  * Extended Base.create/mix support for _buildCfg, to Extensions, mainly so that

    extensions can define a whitelist of statics which need to be copied to the

    main class.

    e.g.

    MyExtension._buildCfg = {

       aggregates:["newPropsToAggregate"...],

       custom: {

           newPropsToCustomMix

       },

       statics: ["newPropsToCopy"]

    };

3.4.1

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  * No changes.

3.4.0

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  * Base now destroys plugins before destroying itself

  * Base.create/mix extensions can now define initializer and

    destructor prototype functions, which will get invoked after

    the initializer for the host class into which they are mixed and

    before it's destructor.

  * Use a hash version of whitelist mix for improved performance.

    Also removed non-required hasOwnProperty check and delete.

3.3.0

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  * Fixed Base.mix when used on a class created using Base.create

  * toString no longer inadvertently stamps the object, however,

    we now stamp Base objects in the constructor, to support

    use cases where the "toString" stamping was implicitly being

    relied upon (e.g. in DD, as hashkeys).

3.2.0

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  * Fixed Base.create to properly isolate ATTRS on extensions

3.1.1

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  * No changes

3.1.0

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  * As the final step in the destroy phase, Base now does a detachAll() to avoid invoking listeners

    which may be waiting to be in an async. step which occurs after destruction.

  * "init" and "destroy" events are now published with the defaultTargetOnly property set to true

  * Added support for MyClass.EVENT_PREFIX to allow developers

    to define their own event prefix

  * Made "init" and "destroy" events fireOnce:true (along with

    "render" in Widget), so that subscriptions made after the

    events are fired, are notified immediately.

  * Dynamic and non-dynamically built classes now have their

    extensions instantiated the same way - during _initHierarchy.

  * Updated ATTRS handling for Base.build, so that ATTRS are

    also aggregated at the attribute configuration object level,

    allowing extensions to add to, or overwrite, attribute

    configuration properties on the host.

  * Added sugar Base.create and Base.mix methods on top of

    Base.build, to simplify the 2 main use cases:

    1) Creating a completely new class which uses extensions.

    2) Mixing in extensions to an existing class.

  * Documented non-attribute on, after, bubbleTargets and plugins

    property support in the Base constructor config argument

3.0.0

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  * Fixed hasImpl method on built classes, to look up the class

    hierarchy for applied extensions.

  * Plugin.Host removed from base-base module and delivered as it's

    own module - "pluginhost"

  * base broken up into..

     base-base: Provides class hierarchy support for ATTRS and

     initialization

     base-build: Provides Extension support in the form of

     Base.build

     base-pluginhost: Augments Plugin.Host to Base, adding plugin

     support

3.0.0 beta 1

------------

  * Config argument for init event now merged into the event facade,

    instead of being passed separately (available as e.cfg).

  * Removed Base.create. On review, considered to be overkill.

    Users can easily create new instances, using Base.build

  * Moved PluginHost down from Widget to Base, since utils and

    Node will also support Plugins.

  * PluginHost.plug and unplug now accept the plugin class as

    arguments [plug(pluginClass, cfg) and unplug(pluginClass)].

  * Split base module up into base-base and base-build.

  * Added lazy attribute initialization support, to improve performance.

    This also removes order dependency when processing ATTRS for a

    particular class.

    If a get/set call is made for an uninitialized attribute A, in the

    getter/setter/validator or valueFns of another attribute B, A will

    be intiailized on the fly.

  * Added ability to subscribe to on/after events through the

    constructor config object, e.g.:

      new MyBaseObject({

         on: {

            init: handlerFn,

            myAttrChange: handlerFn

	     },

	     after: {

	       init: handlerFn,

	       myAttrChange: handlerFn

	     },

	     ...

      });

  * Developers can now override the default clone behavior we use to

    isolate default ATTRS config values, using cloneDefaultValue, e.g.:

    ATTRS = {

      myAttr : {

      	value: AnObjectOrArrayReference

	    cloneDefaultValue: true|false|"deep"|"shallow"

      }

    }

    If the cloneDefaultValue property is not defined, Base will clone

    any Arrays or Object literals which are used as default values when

    configuring attributes for an instance, so that updates to instance

    values do not modify the default value.

    This behavior can be over-ridden using the cloneDefaultValue property:

    true, deep:

      Use Y.clone to protect the default value.

    shallow:

      Use Y.merge, to protect the default value.

    false:

      Don't clone Arrays or Object literals. The value is intended

      to be used by reference, for example, when it points to

      a utility object.

  * Base.plug and Base.unplug used to add static Plugins (default plugins

    for a class). Replaces static PLUGINS array, allowing subclasses to

    easily unplug static plugins added higher up in the hierarchy.

  * Base adds all attributes lazily. This means attributes don't get

    initialized until the first call to get/set, speeding up construction

    of Base based objects.

    Attributes which have setters which set some other state in the object,

    can configure the attribute to disable lazy initialization, by setting

    lazyAdd:false as part of their attribute configuration, so that the setter

    gets invoked during construction.

3.0.0PR1 - Initial release

--------------------------