introduce web_components pkg for consolidated polyfills

pkg/html_import/lib/src/HTMLImports.js

-/*
- * Copyright 2013 The Polymer Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style
- * license that can be found in the LICENSE file.
- */
-
-(function(scope) {
-
-if (!scope) {
-  scope = window.HTMLImports = {flags:{}};
-}
-
-// imports
-
-var xhr = scope.xhr;
-
-// importer
-
-var IMPORT_LINK_TYPE = 'import';
-var STYLE_LINK_TYPE = 'stylesheet';
-
-// highlander object represents a primary document (the argument to 'load')
-// at the root of a tree of documents
-
-// for any document, importer:
-// - loads any linked documents (with deduping), modifies paths and feeds them back into importer
-// - loads text of external script tags
-// - loads text of external style tags inside of <element>, modifies paths
-
-// when importer 'modifies paths' in a document, this includes
-// - href/src/action in node attributes
-// - paths in inline stylesheets
-// - all content inside templates
-
-// linked style sheets in an import have their own path fixed up when their containing import modifies paths
-// linked style sheets in an <element> are loaded, and the content gets path fixups
-// inline style sheets get path fixups when their containing import modifies paths
-
-var loader;
-
-var importer = {
-  documents: {},
-  cache: {},
-  preloadSelectors: [
-    'link[rel=' + IMPORT_LINK_TYPE + ']',
-    'element link[rel=' + STYLE_LINK_TYPE + ']',
-    'template',
-    'script[src]:not([type])',
-    'script[src][type="text/javascript"]'
-  ].join(','),
-  loader: function(inNext) {
-    // construct a loader instance
-    loader = new Loader(importer.loaded, inNext);
-    // alias the loader cache (for debugging)
-    loader.cache = importer.cache;
-    return loader;
-  },
-  load: function(inDocument, inNext) {
-    // construct a loader instance
-    loader = importer.loader(inNext);
-    // add nodes from document into loader queue
-    importer.preload(inDocument);
-  },
-  preload: function(inDocument) {
-    // all preloadable nodes in inDocument
-    var nodes = inDocument.querySelectorAll(importer.preloadSelectors);
-    // from the main document, only load imports
-    // TODO(sjmiles): do this by altering the selector list instead
-    nodes = this.filterMainDocumentNodes(inDocument, nodes);
-    // extra link nodes from templates, filter templates out of the nodes list
-    nodes = this.extractTemplateNodes(nodes);
-    // add these nodes to loader's queue
-    loader.addNodes(nodes);
-  },
-  filterMainDocumentNodes: function(inDocument, nodes) {
-    if (inDocument === document) {
-      nodes = Array.prototype.filter.call(nodes, function(n) {
-        return !isScript(n);
-      });
-    }
-    return nodes;
-  },
-  extractTemplateNodes: function(nodes) {
-    var extra = [];
-    nodes = Array.prototype.filter.call(nodes, function(n) {
-      if (n.localName === 'template') {
-        if (n.content) {
-          var l$ = n.content.querySelectorAll('link[rel=' + STYLE_LINK_TYPE +
-            ']');
-          if (l$.length) {
-            extra = extra.concat(Array.prototype.slice.call(l$, 0));
-          }
-        }
-        return false;
-      }
-      return true;
-    });
-    if (extra.length) {
-      nodes = nodes.concat(extra);
-    }
-    return nodes;
-  },
-  loaded: function(url, elt, resource) {
-    if (isDocumentLink(elt)) {
-      var document = importer.documents[url];
-      // if we've never seen a document at this url
-      if (!document) {
-        // generate an HTMLDocument from data
-        document = makeDocument(resource, url);
-        // resolve resource paths relative to host document
-        path.resolvePathsInHTML(document);
-        // cache document
-        importer.documents[url] = document;
-        // add nodes from this document to the loader queue
-        importer.preload(document);
-      }
-      // store import record
-      elt.import = {
-        href: url,
-        ownerNode: elt,
-        content: document
-      };
-      // store document resource
-      elt.content = resource = document;
-    }
-    // store generic resource
-    // TODO(sorvell): fails for nodes inside <template>.content
-    // see https://code.google.com/p/chromium/issues/detail?id=249381.
-    elt.__resource = resource;
-    // css path fixups
-    if (isStylesheetLink(elt)) {
-      path.resolvePathsInStylesheet(elt);
-    }
-  }
-};
-
-function isDocumentLink(elt) {
-  return isLinkRel(elt, IMPORT_LINK_TYPE);
-}
-
-function isStylesheetLink(elt) {
-  return isLinkRel(elt, STYLE_LINK_TYPE);
-}
-
-function isLinkRel(elt, rel) {
-  return elt.localName === 'link' && elt.getAttribute('rel') === rel;
-}
-
-function isScript(elt) {
-  return elt.localName === 'script';
-}
-
-function makeDocument(resource, url) {
-  // create a new HTML document
-  var doc = resource;
-  if (!(doc instanceof Document)) {
-    doc = document.implementation.createHTMLDocument(IMPORT_LINK_TYPE);
-    // install html
-    doc.body.innerHTML = resource;
-  }
-  // cache the new document's source url
-  doc._URL = url;
-  // establish a relative path via <base>
-  var base = doc.createElement('base');
-  base.setAttribute('href', document.baseURI);
-  doc.head.appendChild(base);
-  // TODO(sorvell): MDV Polyfill intrusion: boostrap template polyfill
-  if (window.HTMLTemplateElement && HTMLTemplateElement.bootstrap) {
-    HTMLTemplateElement.bootstrap(doc);
-  }
-  return doc;
-}
-
-var Loader = function(inOnLoad, inOnComplete) {
-  this.onload = inOnLoad;
-  this.oncomplete = inOnComplete;
-  this.inflight = 0;
-  this.pending = {};
-  this.cache = {};
-};
-
-Loader.prototype = {
-  addNodes: function(inNodes) {
-    // number of transactions to complete
-    this.inflight += inNodes.length;
-    // commence transactions
-    forEach(inNodes, this.require, this);
-    // anything to do?
-    this.checkDone();
-  },
-  require: function(inElt) {
-    var url = path.nodeUrl(inElt);
-    // TODO(sjmiles): ad-hoc
-    inElt.__nodeUrl = url;
-    // deduplication
-    if (!this.dedupe(url, inElt)) {
-      // fetch this resource
-      this.fetch(url, inElt);
-    }
-  },
-  dedupe: function(inUrl, inElt) {
-    if (this.pending[inUrl]) {
-      // add to list of nodes waiting for inUrl
-      this.pending[inUrl].push(inElt);
-      // don't need fetch
-      return true;
-    }
-    if (this.cache[inUrl]) {
-      // complete load using cache data
-      this.onload(inUrl, inElt, loader.cache[inUrl]);
-      // finished this transaction
-      this.tail();
-      // don't need fetch
-      return true;
-    }
-    // first node waiting for inUrl
-    this.pending[inUrl] = [inElt];
-    // need fetch (not a dupe)
-    return false;
-  },
-  fetch: function(url, elt) {
-    var receiveXhr = function(err, resource) {
-      this.receive(url, elt, err, resource);
-    }.bind(this);
-    xhr.load(url, receiveXhr);
-    // TODO(sorvell): blocked on 
-    // https://code.google.com/p/chromium/issues/detail?id=257221
-    // xhr'ing for a document makes scripts in imports runnable; otherwise
-    // they are not; however, it requires that we have doctype=html in
-    // the import which is unacceptable. This is only needed on Chrome
-    // to avoid the bug above.
-    /*
-    if (isDocumentLink(elt)) {
-      xhr.loadDocument(url, receiveXhr);
-    } else {
-      xhr.load(url, receiveXhr);
-    }
-    */
-  },
-  receive: function(inUrl, inElt, inErr, inResource) {
-    if (!inErr) {
-      loader.cache[inUrl] = inResource;
-    }
-    loader.pending[inUrl].forEach(function(e) {
-      if (!inErr) {
-        this.onload(inUrl, e, inResource);
-      }
-      this.tail();
-    }, this);
-    loader.pending[inUrl] = null;
-  },
-  tail: function() {
-    --this.inflight;
-    this.checkDone();
-  },
-  checkDone: function() {
-    if (!this.inflight) {
-      this.oncomplete();
-    }
-  }
-};
-
-var URL_ATTRS = ['href', 'src', 'action'];
-var URL_ATTRS_SELECTOR = '[' + URL_ATTRS.join('],[') + ']';
-var URL_TEMPLATE_SEARCH = '{{.*}}';
-
-var path = {
-  nodeUrl: function(inNode) {
-    return path.resolveUrl(path.getDocumentUrl(document), path.hrefOrSrc(inNode));
-  },
-  hrefOrSrc: function(inNode) {
-    return inNode.getAttribute("href") || inNode.getAttribute("src");
-  },
-  documentUrlFromNode: function(inNode) {
-    return path.getDocumentUrl(inNode.ownerDocument || inNode);
-  },
-  getDocumentUrl: function(inDocument) {
-    var url = inDocument &&
-        // TODO(sjmiles): ShadowDOMPolyfill intrusion
-        (inDocument._URL || (inDocument.impl && inDocument.impl._URL)
-            || inDocument.baseURI || inDocument.URL)
-                || '';
-    // take only the left side if there is a #
-    return url.split('#')[0];
-  },
-  resolveUrl: function(inBaseUrl, inUrl, inRelativeToDocument) {
-    if (this.isAbsUrl(inUrl)) {
-      return inUrl;
-    }
-    var url = this.compressUrl(this.urlToPath(inBaseUrl) + inUrl);
-    if (inRelativeToDocument) {
-      url = path.makeRelPath(path.getDocumentUrl(document), url);
-    }
-    return url;
-  },
-  isAbsUrl: function(inUrl) {
-    return /(^data:)|(^http[s]?:)|(^\/)/.test(inUrl);
-  },
-  urlToPath: function(inBaseUrl) {
-    var parts = inBaseUrl.split("/");
-    parts.pop();
-    parts.push('');
-    return parts.join("/");
-  },
-  compressUrl: function(inUrl) {
-    var parts = inUrl.split("/");
-    for (var i=0, p; i<parts.length; i++) {
-      p = parts[i];
-      if (p === "..") {
-        parts.splice(i-1, 2);
-        i -= 2;
-      }
-    }
-    return parts.join("/");
-  },
-  // make a relative path from source to target
-  makeRelPath: function(inSource, inTarget) {
-    var s, t;
-    s = this.compressUrl(inSource).split("/");
-    t = this.compressUrl(inTarget).split("/");
-    while (s.length && s[0] === t[0]){
-      s.shift();
-      t.shift();
-    }
-    for(var i = 0, l = s.length-1; i < l; i++) {
-      t.unshift("..");
-    }
-    var r = t.join("/");
-    return r;
-  },
-  resolvePathsInHTML: function(root, url) {
-    url = url || path.documentUrlFromNode(root)
-    path.resolveAttributes(root, url);
-    path.resolveStyleElts(root, url);
-    // handle template.content
-    var templates = root.querySelectorAll('template');
-    if (templates) {
-      forEach(templates, function(t) {
-        if (t.content) {
-          path.resolvePathsInHTML(t.content, url);
-        }
-      });
-    }
-  },
-  resolvePathsInStylesheet: function(inSheet) {
-    var docUrl = path.nodeUrl(inSheet);
-    inSheet.__resource = path.resolveCssText(inSheet.__resource, docUrl);
-  },
-  resolveStyleElts: function(inRoot, inUrl) {
-    var styles = inRoot.querySelectorAll('style');
-    if (styles) {
-      forEach(styles, function(style) {
-        style.textContent = path.resolveCssText(style.textContent, inUrl);
-      });
-    }
-  },
-  resolveCssText: function(inCssText, inBaseUrl) {
-    return inCssText.replace(/url\([^)]*\)/g, function(inMatch) {
-      // find the url path, ignore quotes in url string
-      var urlPath = inMatch.replace(/["']/g, "").slice(4, -1);
-      urlPath = path.resolveUrl(inBaseUrl, urlPath, true);
-      return "url(" + urlPath + ")";
-    });
-  },
-  resolveAttributes: function(inRoot, inUrl) {
-    // search for attributes that host urls
-    var nodes = inRoot && inRoot.querySelectorAll(URL_ATTRS_SELECTOR);
-    if (nodes) {
-      forEach(nodes, function(n) {
-        this.resolveNodeAttributes(n, inUrl);
-      }, this);
-    }
-  },
-  resolveNodeAttributes: function(inNode, inUrl) {
-    URL_ATTRS.forEach(function(v) {
-      var attr = inNode.attributes[v];
-      if (attr && attr.value &&
-         (attr.value.search(URL_TEMPLATE_SEARCH) < 0)) {
-        var urlPath = path.resolveUrl(inUrl, attr.value, true);
-        attr.value = urlPath;
-      }
-    });
-  }
-};
-
-xhr = xhr || {
-  async: true,
-  ok: function(inRequest) {
-    return (inRequest.status >= 200 && inRequest.status < 300)
-        || (inRequest.status === 304)
-        || (inRequest.status === 0);
-  },
-  load: function(url, next, nextContext) {
-    var request = new XMLHttpRequest();
-    if (scope.flags.debug || scope.flags.bust) {
-      url += '?' + Math.random();
-    }
-    request.open('GET', url, xhr.async);
-    request.addEventListener('readystatechange', function(e) {
-      if (request.readyState === 4) {
-        next.call(nextContext, !xhr.ok(request) && request,
-          request.response, url);
-      }
-    });
-    request.send();
-    return request;
-  },
-  loadDocument: function(url, next, nextContext) {
-    this.load(url, next, nextContext).responseType = 'document';
-  }
-};
-
-var forEach = Array.prototype.forEach.call.bind(Array.prototype.forEach);
-
-// exports
-
-scope.path = path;
-scope.xhr = xhr;
-scope.importer = importer;
-scope.getDocumentUrl = path.getDocumentUrl;
-scope.IMPORT_LINK_TYPE = IMPORT_LINK_TYPE;
-
-})(window.HTMLImports);