pjax WIP

framework/assets/pjax/LICENSE

+Copyright (c) Chris Wanstrath
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+Software), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
\ No newline at end of file

framework/assets/pjax/jquery.pjax.js

+// jquery.pjax.js
+// copyright chris wanstrath
+// https://github.com/defunkt/jquery-pjax
+
+(function($){
+
+// When called on a container with a selector, fetches the href with
+// ajax into the container or with the data-pjax attribute on the link
+// itself.
+//
+// Tries to make sure the back button and ctrl+click work the way
+// you'd expect.
+//
+// Exported as $.fn.pjax
+//
+// Accepts a jQuery ajax options object that may include these
+// pjax specific options:
+//
+//
+// container - Where to stick the response body. Usually a String selector.
+//             $(container).html(xhr.responseBody)
+//             (default: current jquery context)
+//      push - Whether to pushState the URL. Defaults to true (of course).
+//   replace - Want to use replaceState instead? That's cool.
+//
+// For convenience the second parameter can be either the container or
+// the options object.
+//
+// Returns the jQuery object
+function fnPjax(selector, container, options) {
+  var context = this
+  return this.on('click.pjax', selector, function(event) {
+    var opts = $.extend({}, optionsFor(container, options))
+    if (!opts.container)
+      opts.container = $(this).attr('data-pjax') || context
+    handleClick(event, opts)
+  })
+}
+
+// Public: pjax on click handler
+//
+// Exported as $.pjax.click.
+//
+// event   - "click" jQuery.Event
+// options - pjax options
+//
+// Examples
+//
+//   $(document).on('click', 'a', $.pjax.click)
+//   // is the same as
+//   $(document).pjax('a')
+//
+//  $(document).on('click', 'a', function(event) {
+//    var container = $(this).closest('[data-pjax-container]')
+//    $.pjax.click(event, container)
+//  })
+//
+// Returns nothing.
+function handleClick(event, container, options) {
+  options = optionsFor(container, options)
+
+  var link = event.currentTarget
+
+  if (link.tagName.toUpperCase() !== 'A')
+    throw "$.fn.pjax or $.pjax.click requires an anchor element"
+
+  // Middle click, cmd click, and ctrl click should open
+  // links in a new tab as normal.
+  if ( event.which > 1 || event.metaKey || event.ctrlKey || event.shiftKey || event.altKey )
+    return
+
+  // Ignore cross origin links
+  if ( location.protocol !== link.protocol || location.hostname !== link.hostname )
+    return
+
+  // Ignore anchors on the same page
+  if (link.hash && link.href.replace(link.hash, '') ===
+       location.href.replace(location.hash, ''))
+    return
+
+  // Ignore empty anchor "foo.html#"
+  if (link.href === location.href + '#')
+    return
+
+  var defaults = {
+    url: link.href,
+    container: $(link).attr('data-pjax'),
+    target: link
+  }
+
+  var opts = $.extend({}, defaults, options)
+  var clickEvent = $.Event('pjax:click')
+  $(link).trigger(clickEvent, [opts])
+
+  if (!clickEvent.isDefaultPrevented()) {
+    pjax(opts)
+    event.preventDefault()
+  }
+}
+
+// Public: pjax on form submit handler
+//
+// Exported as $.pjax.submit
+//
+// event   - "click" jQuery.Event
+// options - pjax options
+//
+// Examples
+//
+//  $(document).on('submit', 'form', function(event) {
+//    var container = $(this).closest('[data-pjax-container]')
+//    $.pjax.submit(event, container)
+//  })
+//
+// Returns nothing.
+function handleSubmit(event, container, options) {
+  options = optionsFor(container, options)
+
+  var form = event.currentTarget
+
+  if (form.tagName.toUpperCase() !== 'FORM')
+    throw "$.pjax.submit requires a form element"
+
+  var defaults = {
+    type: form.method.toUpperCase(),
+    url: form.action,
+    data: $(form).serializeArray(),
+    container: $(form).attr('data-pjax'),
+    target: form
+  }
+
+  pjax($.extend({}, defaults, options))
+
+  event.preventDefault()
+}
+
+// Loads a URL with ajax, puts the response body inside a container,
+// then pushState()'s the loaded URL.
+//
+// Works just like $.ajax in that it accepts a jQuery ajax
+// settings object (with keys like url, type, data, etc).
+//
+// Accepts these extra keys:
+//
+// container - Where to stick the response body.
+//             $(container).html(xhr.responseBody)
+//      push - Whether to pushState the URL. Defaults to true (of course).
+//   replace - Want to use replaceState instead? That's cool.
+//
+// Use it just like $.ajax:
+//
+//   var xhr = $.pjax({ url: this.href, container: '#main' })
+//   console.log( xhr.readyState )
+//
+// Returns whatever $.ajax returns.
+function pjax(options) {
+  options = $.extend(true, {}, $.ajaxSettings, pjax.defaults, options)
+
+  if ($.isFunction(options.url)) {
+    options.url = options.url()
+  }
+
+  var target = options.target
+
+  var hash = parseURL(options.url).hash
+
+  var context = options.context = findContainerFor(options.container)
+
+  // We want the browser to maintain two separate internal caches: one
+  // for pjax'd partial page loads and one for normal page loads.
+  // Without adding this secret parameter, some browsers will often
+  // confuse the two.
+  if (!options.data) options.data = {}
+  options.data._pjax = context.selector
+
+  function fire(type, args) {
+    var event = $.Event(type, { relatedTarget: target })
+    context.trigger(event, args)
+    return !event.isDefaultPrevented()
+  }
+
+  var timeoutTimer
+
+  options.beforeSend = function(xhr, settings) {
+    // No timeout for non-GET requests
+    // Its not safe to request the resource again with a fallback method.
+    if (settings.type !== 'GET') {
+      settings.timeout = 0
+    }
+
+    xhr.setRequestHeader('X-PJAX', 'true')
+    xhr.setRequestHeader('X-PJAX-Container', context.selector)
+
+    if (!fire('pjax:beforeSend', [xhr, settings]))
+      return false
+
+    if (settings.timeout > 0) {
+      timeoutTimer = setTimeout(function() {
+        if (fire('pjax:timeout', [xhr, options]))
+          xhr.abort('timeout')
+      }, settings.timeout)
+
+      // Clear timeout setting so jquerys internal timeout isn't invoked
+      settings.timeout = 0
+    }
+
+    options.requestUrl = parseURL(settings.url).href
+  }
+
+  options.complete = function(xhr, textStatus) {
+    if (timeoutTimer)
+      clearTimeout(timeoutTimer)
+
+    fire('pjax:complete', [xhr, textStatus, options])
+
+    fire('pjax:end', [xhr, options])
+  }
+
+  options.error = function(xhr, textStatus, errorThrown) {
+    var container = extractContainer("", xhr, options)
+
+    var allowed = fire('pjax:error', [xhr, textStatus, errorThrown, options])
+    if (options.type == 'GET' && textStatus !== 'abort' && allowed) {
+      locationReplace(container.url)
+    }
+  }
+
+  options.success = function(data, status, xhr) {
+    // If $.pjax.defaults.version is a function, invoke it first.
+    // Otherwise it can be a static string.
+    var currentVersion = (typeof $.pjax.defaults.version === 'function') ?
+      $.pjax.defaults.version() :
+      $.pjax.defaults.version
+
+    var latestVersion = xhr.getResponseHeader('X-PJAX-Version')
+
+    var container = extractContainer(data, xhr, options)
+
+    // If there is a layout version mismatch, hard load the new url
+    if (currentVersion && latestVersion && currentVersion !== latestVersion) {
+      locationReplace(container.url)
+      return
+    }
+
+    // If the new response is missing a body, hard load the page
+    if (!container.contents) {
+      locationReplace(container.url)
+      return
+    }
+
+    pjax.state = {
+      id: options.id || uniqueId(),
+      url: container.url,
+      title: container.title,
+      container: context.selector,
+      fragment: options.fragment,
+      timeout: options.timeout
+    }
+
+    if (options.push || options.replace) {
+      window.history.replaceState(pjax.state, container.title, container.url)
+    }
+
+    // Clear out any focused controls before inserting new page contents.
+    document.activeElement.blur()
+
+    if (container.title) document.title = container.title
+    context.html(container.contents)
+
+    // FF bug: Won't autofocus fields that are inserted via JS.
+    // This behavior is incorrect. So if theres no current focus, autofocus
+    // the last field.
+    //
+    // http://www.w3.org/html/wg/drafts/html/master/forms.html
+    var autofocusEl = context.find('input[autofocus], textarea[autofocus]').last()[0]
+    if (autofocusEl && document.activeElement !== autofocusEl) {
+      autofocusEl.focus();
+    }
+
+    executeScriptTags(container.scripts)
+
+    // Scroll to top by default
+    if (typeof options.scrollTo === 'number')
+      $(window).scrollTop(options.scrollTo)
+
+    // If the URL has a hash in it, make sure the browser
+    // knows to navigate to the hash.
+    if ( hash !== '' ) {
+      // Avoid using simple hash set here. Will add another history
+      // entry. Replace the url with replaceState and scroll to target
+      // by hand.
+      //
+      //   window.location.hash = hash
+      var url = parseURL(container.url)
+      url.hash = hash
+
+      pjax.state.url = url.href
+      window.history.replaceState(pjax.state, container.title, url.href)
+
+      var target = $(url.hash)
+      if (target.length) $(window).scrollTop(target.offset().top)
+    }
+
+    fire('pjax:success', [data, status, xhr, options])
+  }
+
+
+  // Initialize pjax.state for the initial page load. Assume we're
+  // using the container and options of the link we're loading for the
+  // back button to the initial page. This ensures good back button
+  // behavior.
+  if (!pjax.state) {
+    pjax.state = {
+      id: uniqueId(),
+      url: window.location.href,
+      title: document.title,
+      container: context.selector,
+      fragment: options.fragment,
+      timeout: options.timeout
+    }
+    window.history.replaceState(pjax.state, document.title)
+  }
+
+  // Cancel the current request if we're already pjaxing
+  var xhr = pjax.xhr
+  if ( xhr && xhr.readyState < 4) {
+    xhr.onreadystatechange = $.noop
+    xhr.abort()
+  }
+
+  pjax.options = options
+  var xhr = pjax.xhr = $.ajax(options)
+
+  if (xhr.readyState > 0) {
+    if (options.push && !options.replace) {
+      // Cache current container element before replacing it
+      cachePush(pjax.state.id, context.clone().contents())
+
+      window.history.pushState(null, "", stripPjaxParam(options.requestUrl))
+    }
+
+    fire('pjax:start', [xhr, options])
+    fire('pjax:send', [xhr, options])
+  }
+
+  return pjax.xhr
+}
+
+// Public: Reload current page with pjax.
+//
+// Returns whatever $.pjax returns.
+function pjaxReload(container, options) {
+  var defaults = {
+    url: window.location.href,
+    push: false,
+    replace: true,
+    scrollTo: false
+  }
+
+  return pjax($.extend(defaults, optionsFor(container, options)))
+}
+
+// Internal: Hard replace current state with url.
+//
+// Work for around WebKit
+//   https://bugs.webkit.org/show_bug.cgi?id=93506
+//
+// Returns nothing.
+function locationReplace(url) {
+  window.history.replaceState(null, "", "#")
+  window.location.replace(url)
+}
+
+
+var initialPop = true
+var initialURL = window.location.href
+var initialState = window.history.state
+
+// Initialize $.pjax.state if possible
+// Happens when reloading a page and coming forward from a different
+// session history.
+if (initialState && initialState.container) {
+  pjax.state = initialState
+}
+
+// Non-webkit browsers don't fire an initial popstate event
+if ('state' in window.history) {
+  initialPop = false
+}
+
+// popstate handler takes care of the back and forward buttons
+//
+// You probably shouldn't use pjax on pages with other pushState
+// stuff yet.
+function onPjaxPopstate(event) {
+  var state = event.state
+
+  if (state && state.container) {
+    // When coming forward from a separate history session, will get an
+    // initial pop with a state we are already at. Skip reloading the current
+    // page.
+    if (initialPop && initialURL == state.url) return
+
+    // If popping back to the same state, just skip.
+    // Could be clicking back from hashchange rather than a pushState.
+    if (pjax.state.id === state.id) return
+
+    var container = $(state.container)
+    if (container.length) {
+      var direction, contents = cacheMapping[state.id]
+
+      if (pjax.state) {
+        // Since state ids always increase, we can deduce the history
+        // direction from the previous state.
+        direction = pjax.state.id < state.id ? 'forward' : 'back'
+
+        // Cache current container before replacement and inform the
+        // cache which direction the history shifted.
+        cachePop(direction, pjax.state.id, container.clone().contents())
+      }
+
+      var popstateEvent = $.Event('pjax:popstate', {
+        state: state,
+        direction: direction
+      })
+      container.trigger(popstateEvent)
+
+      var options = {
+        id: state.id,
+        url: state.url,
+        container: container,
+        push: false,
+        fragment: state.fragment,
+        timeout: state.timeout,
+        scrollTo: false
+      }
+
+      if (contents) {
+        container.trigger('pjax:start', [null, options])
+
+        if (state.title) document.title = state.title
+        container.html(contents)
+        pjax.state = state
+
+        container.trigger('pjax:end', [null, options])
+      } else {
+        pjax(options)
+      }
+
+      // Force reflow/relayout before the browser tries to restore the
+      // scroll position.
+      container[0].offsetHeight
+    } else {
+      locationReplace(location.href)
+    }
+  }
+  initialPop = false
+}
+
+// Fallback version of main pjax function for browsers that don't
+// support pushState.
+//
+// Returns nothing since it retriggers a hard form submission.
+function fallbackPjax(options) {
+  var url = $.isFunction(options.url) ? options.url() : options.url,
+      method = options.type ? options.type.toUpperCase() : 'GET'
+
+  var form = $('<form>', {
+    method: method === 'GET' ? 'GET' : 'POST',
+    action: url,
+    style: 'display:none'
+  })
+
+  if (method !== 'GET' && method !== 'POST') {
+    form.append($('<input>', {
+      type: 'hidden',
+      name: '_method',
+      value: method.toLowerCase()
+    }))
+  }
+
+  var data = options.data
+  if (typeof data === 'string') {
+    $.each(data.split('&'), function(index, value) {
+      var pair = value.split('=')
+      form.append($('<input>', {type: 'hidden', name: pair[0], value: pair[1]}))
+    })
+  } else if (typeof data === 'object') {
+    for (key in data)
+      form.append($('<input>', {type: 'hidden', name: key, value: data[key]}))
+  }
+
+  $(document.body).append(form)
+  form.submit()
+}
+
+// Internal: Generate unique id for state object.
+//
+// Use a timestamp instead of a counter since ids should still be
+// unique across page loads.
+//
+// Returns Number.
+function uniqueId() {
+  return (new Date).getTime()
+}
+
+// Internal: Strips _pjax param from url
+//
+// url - String
+//
+// Returns String.
+function stripPjaxParam(url) {
+  return url
+    .replace(/\?_pjax=[^&]+&?/, '?')
+    .replace(/_pjax=[^&]+&?/, '')
+    .replace(/[\?&]$/, '')
+}
+
+// Internal: Parse URL components and returns a Locationish object.
+//
+// url - String URL
+//
+// Returns HTMLAnchorElement that acts like Location.
+function parseURL(url) {
+  var a = document.createElement('a')
+  a.href = url
+  return a
+}
+
+// Internal: Build options Object for arguments.
+//
+// For convenience the first parameter can be either the container or
+// the options object.
+//
+// Examples
+//
+//   optionsFor('#container')
+//   // => {container: '#container'}
+//
+//   optionsFor('#container', {push: true})
+//   // => {container: '#container', push: true}
+//
+//   optionsFor({container: '#container', push: true})
+//   // => {container: '#container', push: true}
+//
+// Returns options Object.
+function optionsFor(container, options) {
+  // Both container and options
+  if ( container && options )
+    options.container = container
+
+  // First argument is options Object
+  else if ( $.isPlainObject(container) )
+    options = container
+
+  // Only container
+  else
+    options = {container: container}
+
+  // Find and validate container
+  if (options.container)
+    options.container = findContainerFor(options.container)
+
+  return options
+}
+
+// Internal: Find container element for a variety of inputs.
+//
+// Because we can't persist elements using the history API, we must be
+// able to find a String selector that will consistently find the Element.
+//
+// container - A selector String, jQuery object, or DOM Element.
+//
+// Returns a jQuery object whose context is `document` and has a selector.
+function findContainerFor(container) {
+  container = $(container)
+
+  if ( !container.length ) {
+    throw "no pjax container for " + container.selector
+  } else if ( container.selector !== '' && container.context === document ) {
+    return container
+  } else if ( container.attr('id') ) {
+    return $('#' + container.attr('id'))
+  } else {
+    throw "cant get selector for pjax container!"
+  }
+}
+
+// Internal: Filter and find all elements matching the selector.
+//
+// Where $.fn.find only matches descendants, findAll will test all the
+// top level elements in the jQuery object as well.
+//
+// elems    - jQuery object of Elements
+// selector - String selector to match
+//
+// Returns a jQuery object.
+function findAll(elems, selector) {
+  return elems.filter(selector).add(elems.find(selector));
+}
+
+function parseHTML(html) {
+  return $.parseHTML(html, document, true)
+}
+
+// Internal: Extracts container and metadata from response.
+//
+// 1. Extracts X-PJAX-URL header if set
+// 2. Extracts inline <title> tags
+// 3. Builds response Element and extracts fragment if set
+//
+// data    - String response data
+// xhr     - XHR response
+// options - pjax options Object
+//
+// Returns an Object with url, title, and contents keys.
+function extractContainer(data, xhr, options) {
+  var obj = {}
+
+  // Prefer X-PJAX-URL header if it was set, otherwise fallback to
+  // using the original requested url.
+  obj.url = stripPjaxParam(xhr.getResponseHeader('X-PJAX-URL') || options.requestUrl)
+
+  // Attempt to parse response html into elements
+  if (/<html/i.test(data)) {
+    var $head = $(parseHTML(data.match(/<head[^>]*>([\s\S.]*)<\/head>/i)[0]))
+    var $body = $(parseHTML(data.match(/<body[^>]*>([\s\S.]*)<\/body>/i)[0]))
+  } else {
+    var $head = $body = $(parseHTML(data))
+  }
+
+  // If response data is empty, return fast
+  if ($body.length === 0)
+    return obj
+
+  // If there's a <title> tag in the header, use it as
+  // the page's title.
+  obj.title = findAll($head, 'title').last().text()
+
+  if (options.fragment) {
+    // If they specified a fragment, look for it in the response
+    // and pull it out.
+    if (options.fragment === 'body') {
+      var $fragment = $body
+    } else {
+      var $fragment = findAll($body, options.fragment).first()
+    }
+
+    if ($fragment.length) {
+      obj.contents = $fragment.contents()
+
+      // If there's no title, look for data-title and title attributes
+      // on the fragment
+      if (!obj.title)
+        obj.title = $fragment.attr('title') || $fragment.data('title')
+    }
+
+  } else if (!/<html/i.test(data)) {
+    obj.contents = $body
+  }
+
+  // Clean up any <title> tags
+  if (obj.contents) {
+    // Remove any parent title elements
+    obj.contents = obj.contents.not(function() { return $(this).is('title') })
+
+    // Then scrub any titles from their descendants
+    obj.contents.find('title').remove()
+
+    // Gather all script[src] elements
+    obj.scripts = findAll(obj.contents, 'script[src]').remove()
+    obj.contents = obj.contents.not(obj.scripts)
+  }
+
+  // Trim any whitespace off the title
+  if (obj.title) obj.title = $.trim(obj.title)
+
+  return obj
+}
+
+// Load an execute scripts using standard script request.
+//
+// Avoids jQuery's traditional $.getScript which does a XHR request and
+// globalEval.
+//
+// scripts - jQuery object of script Elements
+//
+// Returns nothing.
+function executeScriptTags(scripts) {
+  if (!scripts) return
+
+  var existingScripts = $('script[src]')
+
+  scripts.each(function() {
+    var src = this.src
+    var matchedScripts = existingScripts.filter(function() {
+      return this.src === src
+    })
+    if (matchedScripts.length) return
+
+    var script = document.createElement('script')
+    script.type = $(this).attr('type')
+    script.src = $(this).attr('src')
+    document.head.appendChild(script)
+  })
+}
+
+// Internal: History DOM caching class.
+var cacheMapping      = {}
+var cacheForwardStack = []
+var cacheBackStack    = []
+
+// Push previous state id and container contents into the history
+// cache. Should be called in conjunction with `pushState` to save the
+// previous container contents.
+//
+// id    - State ID Number
+// value - DOM Element to cache
+//
+// Returns nothing.
+function cachePush(id, value) {
+  cacheMapping[id] = value
+  cacheBackStack.push(id)
+
+  // Remove all entires in forward history stack after pushing
+  // a new page.
+  while (cacheForwardStack.length)
+    delete cacheMapping[cacheForwardStack.shift()]
+
+  // Trim back history stack to max cache length.
+  while (cacheBackStack.length > pjax.defaults.maxCacheLength)
+    delete cacheMapping[cacheBackStack.shift()]
+}
+
+// Shifts cache from directional history cache. Should be
+// called on `popstate` with the previous state id and container
+// contents.
+//
+// direction - "forward" or "back" String
+// id        - State ID Number
+// value     - DOM Element to cache
+//
+// Returns nothing.
+function cachePop(direction, id, value) {
+  var pushStack, popStack
+  cacheMapping[id] = value
+
+  if (direction === 'forward') {
+    pushStack = cacheBackStack
+    popStack  = cacheForwardStack
+  } else {
+    pushStack = cacheForwardStack
+    popStack  = cacheBackStack
+  }
+
+  pushStack.push(id)
+  if (id = popStack.pop())
+    delete cacheMapping[id]
+}
+
+// Public: Find version identifier for the initial page load.
+//
+// Returns String version or undefined.
+function findVersion() {
+  return $('meta').filter(function() {
+    var name = $(this).attr('http-equiv')
+    return name && name.toUpperCase() === 'X-PJAX-VERSION'
+  }).attr('content')
+}
+
+// Install pjax functions on $.pjax to enable pushState behavior.
+//
+// Does nothing if already enabled.
+//
+// Examples
+//
+//     $.pjax.enable()
+//
+// Returns nothing.
+function enable() {
+  $.fn.pjax = fnPjax
+  $.pjax = pjax
+  $.pjax.enable = $.noop
+  $.pjax.disable = disable
+  $.pjax.click = handleClick
+  $.pjax.submit = handleSubmit
+  $.pjax.reload = pjaxReload
+  $.pjax.defaults = {
+    timeout: 650,
+    push: true,
+    replace: false,
+    type: 'GET',
+    dataType: 'html',
+    scrollTo: 0,
+    maxCacheLength: 20,
+    version: findVersion
+  }
+  $(window).on('popstate.pjax', onPjaxPopstate)
+}
+
+// Disable pushState behavior.
+//
+// This is the case when a browser doesn't support pushState. It is
+// sometimes useful to disable pushState for debugging on a modern
+// browser.
+//
+// Examples
+//
+//     $.pjax.disable()
+//
+// Returns nothing.
+function disable() {
+  $.fn.pjax = function() { return this }
+  $.pjax = fallbackPjax
+  $.pjax.enable = enable
+  $.pjax.disable = $.noop
+  $.pjax.click = $.noop
+  $.pjax.submit = $.noop
+  $.pjax.reload = function() { window.location.reload() }
+
+  $(window).off('popstate.pjax', onPjaxPopstate)
+}
+
+
+// Add the state property to jQuery's event object so we can use it in
+// $(window).bind('popstate')
+if ( $.inArray('state', $.event.props) < 0 )
+  $.event.props.push('state')
+
+// Is pjax supported by this browser?
+$.support.pjax =
+  window.history && window.history.pushState && window.history.replaceState &&
+  // pushState isn't reliable on iOS until 5.
+  !navigator.userAgent.match(/((iPod|iPhone|iPad).+\bOS\s+[1-4]|WebApps\/.+CFNetwork)/)
+
+$.support.pjax ? enable() : disable()
+
+})(jQuery);

framework/widgets/MaskedInputAsset.php

@@ -6,6 +6,7 @@
  */
 
 namespace yii\widgets;
+
 use yii\web\AssetBundle;
 
 /**

framework/widgets/Pjax.php

+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\widgets;
+
+use Yii;
+use yii\base\Widget;
+use yii\helpers\Json;
+
+/**
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class Pjax extends Widget
+{
+	public $links = 'a';
+
+	public function init()
+	{
+		ob_start();
+		ob_implicit_flush(false);
+		echo '<div id="' . $this->getId() . '">';
+	}
+
+	public function run()
+	{
+		echo '</div>';
+		$content = ob_get_clean();
+
+		$headers = Yii::$app->getRequest()->getHeaders();
+		if ($headers->get('X-Pjax') && ($selector = $headers->get('X-PJax-Container')) === '#' . $this->getId()) {
+			// todo: send the response and terminate the application
+		} else {
+			$this->registerClientScript();
+			return $content;
+		}
+	}
+
+	/**
+	 * Registers the needed JavaScript.
+	 */
+	public function registerClientScript()
+	{
+		$view = $this->getView();
+		PjaxAsset::register($view);
+		$js = 'jQuery(document).pjax("' . Json::encode($this->links) . '", "#' . $this->getId() . '");';
+		$view->registerJs($js);
+	}
+}

framework/widgets/PjaxAsset.php

+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\widgets;
+
+use yii\web\AssetBundle;
+
+/**
+ * This asset bundle provides the javascript files required by [[yii\widgets\Pjax]] widget.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class PjaxAsset extends AssetBundle
+{
+	public $sourcePath = '@yii/assets';
+	public $js = [
+		'pjax/jquery.pjax.js',
+	];
+	public $depends = [
+		'yii\web\YiiAsset',
+	];
+}