Preview Release v2.0.0-rc.6

Meaningful Changes

• Start supporting compilation with Closure Compiler in 'ADVANCED' mode
• Allow setProperties to set readOnly properties
  • this.setProperties({readOnlyProp: value}, true)
• Prevent properties from reverting to default value after boot when the property has no observers

Raw Notes

• [ci skip] Fix API docs (commit)

• Guard against overwriting bound values with hasOwnProperty. Fixes #4540 (commit)

• [ci skip] reduce warnings (commit)

• fix globals for goog.reflect.objectProperty -> JSCompiler_renameProperty swap (commit)

• [ci skip] remove outdated externs file (commit)

• lint and compile successfully (commit)

• update dependencies (commit)

• Rename setPrivate -> setReadOnly (commit)

• Add setPrivate arg to setProperties (commit)

• Never accidental test change (commit)

• Remove unused @method (commit)

• Standardize @return, @param, type case. (commit)

• Fix jsdoc warnings. (commit)

• jsdoc fixes. (commit)

• Fix jsdoc issues. (commit)

• Fix jsdoc issues. (commit)

• Enable error on jsdoc mistake. (commit)

• fix @license comments & shadycss imports. Remove custom style from externs (commit)

• closure advanced compilation (commit)

Stable Release v1.9.1

Meaningful Changes

• Fix use of this.resolveUrl() function in the properties block
• Fix hybrid use of dom-if, dom-bind, and dom-repeat with 2.x wrapper elements to stamp content above the wrapper

Example:

<!-- content should be stamped here -->
<dom-bind>
  <template is="dom-bind">
    <!-- content -->
  </template>
</dom-bind>

Raw Notes

• Remove use of ES6 API. (commit)

• Remove use of ES6 API. (commit)

• Ensure optimization uses hybrid parentNode (commit)

• Use local parentNode (commit)

• Capture hybridDomRepeat. (commit)

• Fix dom-if detachment (commit)

• Add dom-if test for add/remove. (commit)

• Add test for add & remove (commit)

• Add 2.x hybrid affordances for stamping template content. Fixes #4536 (commit)

• Fix lint (commit)

• Make tests more strict. (commit)

• Use _importPath in resolveUrl so it available early. Fixes #4532 (commit)

• [ci skip] update Changelog (commit)

v2.0.0-rc.5

Meaningful Changes

• Add more override points for controlling template stamping
  • Adds override points for _parseBindings and _evaluateBinding
  • Adds support for runtime template binding
  • Moves ready(), _hasAccessor tracking, and instance property swizzle at ready time to PropertyAccessors
  • Other refactoring and cleanup
  • More information on using binding overrides at #4510 (comment)
• Add $ id map to dom-bind elements
• Refactor PropertyEffects mixin with a more usable API
• Support listening to Gesture events with dom-bind elements

Raw Notes

• Eliminate rest args for better perf on stable chrome. (commit)

• Fix perf regressions. (commit)

• Move second tap test to the correct spot. (commit)

• Add GestureEventListeners to dom-bind. (commit)

• Add more comments (commit)

• [ci skip] Fix comment. (commit)

• alias another way (commit)

• use chrome beta (commit)

• Add more HTMLImports.whenReady (commit)

• Address feedback from review: * Refactor _bindTemplate to remove problematic hasCreatedAccessors * Remove vestigial dom from _bindTemplate call * Rename _unstampTemplate to _removeBoundDom * Add infoIndex to nodeInfo (and renamed parent & index) * Add test to ensure runtime accessors created for new props in runtime stamped template * Changed custom binding test to use different prop names * Added test for #first count after removing bound dom (commit)

• Fix lint error. (commit)

• Ensure prototype wasn't affected by runtime effects. (commit)

• Add tests for adding/removing runtime property effects. (commit)

• Added tests for custom parsing, effects, and binding. (commit)

• Add initial runtime stamping tests. (commit)

• Fix changelog generation (commit)

• Address feedback based on review. * PropertyAccessors must call _flushProperties to enable * Avoid tearing off oldProps (unnecessary) * Add addBinding docs * Merge notifyListeners into setupBindings * Add comment re: path-bindings not being overridable * Remove dom argument from _bindTemplate * Rename _stampBoundTemplate back to _stampTemplate (commit)

• Put $ on dom, and assign to element as needed. Eliminate _templateInfo reference. (commit)

• Fix _hasAccessor for readOnly. Collapse addBinding & addBindingEffects (commit)

• Improvements to binding API: - Adds override points for _parseBindings and _evaluateBinding - Adds support for runtime template binding - Moves ready(), _hasAccessor tracking, and instance property swizzle at ready time to PropertyAccessors (commit)

Stable Release v1.9.0

New Features

Two new properties were added to all Polymer elements for forward-compatibility with 2.0 (for use in "2.0 hybrid" elements): importPath and rootPath.

The importPath property defaults to the element's HTMLImport document URL path.

The rootPath property defaults to the main document URL's path but may be globally overridden via Polymer = { rootPath: '...' } prior to loading polymer.html.

Inside element templates, users can now use property binding (e.g. src$="[[importPath]]foo.jpg" or src$="[[rootPath]]foo.png") to explicitly declare what the URL is relative to, rather than relying on Polymer 1.x's automatic URL rewriting, which has been removed in 2.x.

It may be useful to override rootPath to provide a stable application mount path when using client side routing so that an element template can refer to "application absolute" paths.

Raw Notes

• [ci skip] skip looking in build log, again (commit)

• [ci skip] backport changelog fixes (commit)

• • allow setting rootPath
  • disallow setting importPath (this is supported in 2.x but not 1.x) (commit)

• Add importPath and rootPath to support 2.x hybrid compatible elements. (commit)

• [ci skip] Update Changelog (commit)

• Add missing semicolon after variable assignment (commit)

• Update PRIMER.md (commit)

v2.0.0-rc.4

Meaningful Changes

• Reintroduce beforeRegister to install dynamic property effects. In a difference from 1.x, is property cannot be set in this function.
• Maintain 1.x ordering of ready() lifecycle call, where children will always ready() before the parent.
• Implement disable-upgrade feature from 1.x
• Implement new lazy-upgrade feature with a mixin to lazily upgrade elements marked with disable-upgrade
  • In this example, the <x-disabled> children of <x-lazy> will upgrade asynchronously, but in the order of $.a, $.c, and then $.b

  <dom-module id="x-lazy">
  <template>
    <!-- x-disabled will automatically be upgraded asynchronously -->
    <x-disabled id="a" disable-upgrade lazy-upgrade="1"></x-disabled>
    <x-disabled id="b" disable-upgrade lazy-upgrade="3"></x-disabled>
    <x-disabled id="c" disable-upgrade lazy-upgrade="2"></x-disabled>
  </template>
    <script>
      class XLazy extends Polymer.LazyUpgrade(Polymer.Element) {
        static get is() { return 'x-lazy' }
      }
      customElements.define(XLazy.is, XLazy);
    </script>
  </dom-module>

• Allow elements to override template binding functions

Raw Notes

• fix lint error (commit)

• Only style elements with templates (commit)

• [ci skip] note safari bugs (commit)

• Various Safari 10.1 fixes (commit)

• Add @memberof annotation for Polymer.Debouncer (commit)

• Import mutable-data.html in dom-bind (commit)

• Correct changelog version title (commit)

• Fix readme. (commit)

• tighten up custom-style-late test (commit)

• Fixes #4478 by adding a better warning for attributes that cannot deserialize from JSON. (commit)

• Adds back the beforeRegister method. Users can no longer set the is property in this method; however, dynamic property effects can still be installed here. (commit)

• Fixes #4447. Re-introduce the hostStack in order to maintain “client before host” ordering when _flushProperties is called before connectedCallback (e.g. as Templatize does). (commit)

• Fix custom-style-late tests (commit)

• Add test for ensuring complicated mixin ordering is correct (commit)

• move lazy-upgrade out to separate mixins repo (commit)

• Only check bounding client rect on clicks that target elements (commit)

• Adds tests from #4099. The other changes from the PR are no longer needed. (commit)

• clean up code, factor processing lazy candidates, better docs (commit)

• Update templatize.html (commit)

• Doc fix (correct callback name) (commit)

• Fixed tempaltize -> templatize typo (commit)

• Work around IE/Edge bug with :not([attr]) selectors (commit)

• Remove support for lazy-upgrade inside dom-if and dom-repeat (commit)

• Fix image in README (commit)

• Remove useless id check on mixins (commit)

• move dom-change listener for lazy-upgrade before super.ready() (commit)

• [ci skip] Update doc (commit)

• [ci skip] Update doc (commit)

• Add API docs. (commit)

• nodeInfo -> nodeInfoList (commit)

• Updates based on PR feedback. API docs in progress. (commit)

• • ensure element cannot return to “disabled” state after upgrading. * ensure nested beforeNextRender calls always go before the next render * ensure nested afterNextRender are called after additional renders (commit)

• Fixes #4437. Ensure _registered is called 1x for each element class using LegacyElementMixin. Ensure that a behaviors’s registered method is called for any extending class. (commit)

• Separate binding-specific code from template stamp. Expose override points. (commit)

• Use webcomponents-lite for test (commit)

• add lazy-upgrade tests (commit)

• make a mixin for lazy upgrading (commit)

• implements disable-upgrade attribute which prevents readying an element until the attribute is removed. (commit)

Preview Release v2.0.0-rc.3

Meaningful Changes

• Allow properties, behaviors, observers, hostAttributes, and listeners to be set in Polymer({}) calls
• Behaviors can only be set on the element prototype

Raw Notes

• add properties, behaviors, observers, hostAttributes, listeners on prototype (commit)

• [skip ci] update test comments (commit)

• better comment (commit)

• get behaviors only from prototypes (commit)

• behaviors ONLY on the prototype (commit)

• add instance behaviors (commit)

• [ci skip] minor doc edits. (commit)

• [ci skip] expand range of dependencies to all rcs (commit)

Preview Release v2.0.0-rc.2

Meaningful Changes

• Hybrid elements can make template instances with mutable data
• Fire dom-change events with the composed flag

Raw Notes

• another test fix. (commit)

• fix behavior warn test. (commit)

• update to latest webcompnents rc. (commit)

• move mutable data mixin to be loaded by polymer.html (commit)

• Fix 4387. Ensure dom-change fired with composed: true. (commit)

• Allow hybrid elements (like iron-list) to make template instances with mutable data (commit)

• Don't override the goog namespace if it already exists (commit)

• Use correct version (commit)

• Fix spelling error (commit)

• [ci skip] Fix note re: transpilation (commit)

• [ci skip] Remove obsolete note re: pre-upgrade attribute vs. property priority (commit)

• [ci skip] Fix note re: attached (commit)

• [ci skip] Add back intro README content from 1.x, updated to 2.x syntax. (commit)

Preview Release v2.0.0-rc.1

Meaningful Changes

The following notable changes have been made since the 2.0 Preview announcement.

• The config getter on element classes has been replaced by individual properties and
  observers getters, more closely resembling the 1.x syntax.

  static get properties() {
    return {
      aProp: String,
      bProp: Number
    }
  }
  static get observers() {
    return [
      '_observeStuff(aProp,bProp)'
    ]
  }

• 1.x-style dirty checking has been reinstated for better performance. An optional mixin is
  available for elements to skip dirty checking of objects and arrays, which may be more easy to
  integrate with some state management systems. For details, see
  Using the MutableData mixin in Data system concepts.

• Support for dynamically-created custom-style elements has been added.

• Support for the external style sheet syntax, <link rel="import" type="css"> has
  been added. This was deprecated in 1.x, but will be retained until an alternate solution is
  available for importing unprocessed CSS.

• New properties rootPath and basePath were added to Polymer.Element to allow authors
  to configure how URLs are rewritten inside templates. For details, see the
  Update URLs in templates in the Upgrade guide.

Stable Release v1.8.1

Meaningful Changes

• Fix for UC browser's non-standard properties property on instances of HTMLElement: #4314
• Experimental feature to avoid inlining <style include> and instead use multiple <style> elements
  • Only usable with native ShadowDOM
  • Can be enabled with preserveStyleIncludes flag, but requires dom=shadow setting

Raw Notes

• Exclude SD polyfill tests for Edge due to lack of workarounds for Edge DocFrag bugs. (commit)
• [ci skip] Update comment to include reference to problem browser. (commit)
• Check documentElement instead of body to guarantee it's there. (commit)
• add tests (commit)
• Adds a setting preserveStyleIncludes which, when used with a shadow dom targeted css build and native custom properties, will copy styles into the Shadow DOM template rather than collapsing them into a single style. This will (1) allow the browser to optimize parsing of shared styles because they remain intact, (2) reduce the size of the css build resources when shared styles are used since they are not pre-collapsed. This option does perform registration runtime work to add included styles to element templates. (commit)
• Fix test failures by feature detecting instance properties accessors. Can't rely on __proto__ on IE10, but that browser doesn't need to avoid properties. (commit)
• Read properties off of proto during configuration. (commit)
• remove cruft. (commit)
• Ensure disable-upgrade elements are not "configured". Fixes #4302 (commit)
• change lastresponse to last-response in dom-bind example (commit)

Stable Release v1.8.0

New Features

Suppress notification events

• New global setting: Polymer = { suppressTemplateNotifications: true }
  • suppresses dom-change and rendered-item-count events from dom-if, dom-repeat, and dom-bind. Users can opt back into dom-change events by setting the notify-dom-change attribute (notifyDomChange: true property) to dom-if/dom-repeat instances.
• New global setting: Polymer = { suppressBindingNotifications: true }
  • disables notify effects when propagating data downward via bindings. Generally these are never useful unless users are explicitly doing something like <my-el foo="{{foo}} on-foo-changed="{{handleFoo}}"> (which is generally unnecessary since the host element doing the binding can use a foo observer) or calling addEventListener('foo-changed', ...) on an element where foo is bound. We attempted to make this the default some time back but needed to revert it when we found via #3077 that users were indeed doing this in corner-case scenarios. Users that avoid these patterns can enjoy the potentially significant benefit of suppressing unnecessary events during downward data flow by opting into this flag.

disable-upgrade attribute

Adds a disable-upgrade attribute API for all Polymer elements when global opt-in setting Polymer = { disableUpgradeEnabled: true } is set. This is a lightweight feature useful for performance tuning an application, giving fine-grained control over individual element instantiation cost.

When an element is marked with the disable-upgrade attribute, its createdCallback will return early without performing any of the normal Polymer element initialization steps (e.g. stamping template, setting default properties, running observers, etc.). The element will behave similar to an element that has not had its definition loaded, except that it will actually have the correct prototype (as such, methods should not be called on the element until its disable-upgrade attribute has been removed).

Removing the disable-upgrade attribute will then cause the element to boot up, initialize its properties, stamp its template, etc.

Note this feature is implemented as an attribute API only. There is no corresponding disableUpgrade property. As such, any bindings should be via attribute bindings, e.g. <my-element disable-upgrade$="{{!loggedIn}}">.

Meaningful Changes

<template strip-whitespace>

The strip-whitespace attribute is now recursive to descendant templates, stripping whitespace from nested <template is="dom-repeat"> and <template is="dom-if> elements.

Raw Notes

• Add comment. (commit)
• Only keep disable-upgrade attribute if it is an attribute binding. (commit)
• spacing. (commit)
• Update webcomponentsjs dependency (commit)
• Change isInert to disable-upgrade and feature is now supported only via the disable-upgrade attribute. (commit)
• Add tests for is-inert (commit)
• Prevent annotator from removing the is-inert attribute. (commit)
• fixes for users of Polymer.Class (commit)
• Add support for isInert to allow elements to boot up in an inert state. e.g. <x-foo is-inert></x-foo>. Setting xFoo.isInert = false causes the element to boot up. (commit)
• Small typos updated (commit)
• work around older firefox handling of the "properties" property on HTMLElement prototype (commit)
• improve comments (commit)
• Add comments. Behavior fast copy flag changed to _noAccessors. (commit)
• Fix tests on IE10 and simplify constructor shortcut. (commit)
• Make dom-module work on older Safari. (commit)
• micro-optimizations: (1) favor mixin over extends where possible, (2) unroll behavior lifecycle calls, (3) avoid creating a custom constructor when not used, (4) provide _skipDefineProperty setting on behaviors which copies properties via assignment rather than copyOwnProperty (commit)
• Ensure done. (commit)
• Test positive case of suppressBindingNotifications (commit)
• Add notifyDomBind to dom-bind. (commit)
• Test Polymer.Settings inside test. (commit)
• Revert unnecessary change. (commit)
• Fix test lint issue. (commit)
• Add global flags to suppress unnecessary notification events. Fixes #4262. * Polymer.Settings.suppressTemplateNotifications- disables dom-change and rendered-item-count events from dom-if, dom-repeat, and don-bind. Users can opt back into dom-change events by setting the notify-dom-change attribute (notifyDomChange: true property) to dom-if/don-repeat instances. * Polymer.Settings.suppressBindingNotifications - disables notify effects when propagating data downward via bindings. Generally these are never useful unless users are explicitly doing something like <my-el foo="{{foo}} on-foo-changed="{{handleFoo}}"> or calling addEventListener('foo-changed', ...) on an element where foo is bound (we attempted to make this the default some time back but needed to revert it when we found via #3077 that users were indeed doing this). Users that avoid these patterns can enjoy the potentially significant benefit of suppressing unnecessary events during downward data flow by opting into this flag. (commit)
• Fix strip-whitespace for nested templates. (commit)
• [ci skip] update changelog v1.7.1 (commit)
• Close backtick in ISSUE_TEMPLATE.md (commit)