implement workaround for https://www.w3.org/Bugs/Public/show_bug.cgi?…

…id=25007
googlearchive · May 17, 2014 · 1ee7357 · 1ee7357
1 parent 1c796ec
commit 1ee7357
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Showing 3 changed files with 79 additions and 3 deletions.
diff --git a/src/HTMLImports.js b/src/HTMLImports.js
@@ -217,8 +217,7 @@ function watchImportsLoad(callback, doc) {
   var loaded = 0, l = imports.length;
   function checkDone(d) { 
     if (loaded == l) {
-      // go async to ensure parser isn't stuck on a script tag
-      requestAnimationFrame(callback);
+      callback && callback();
     }
   }
   function loadedImport(e) {
@@ -240,10 +239,50 @@ function watchImportsLoad(callback, doc) {
 }
 
 function isImportLoaded(link) {
-  return useNative ? (link.import && (link.import.readyState !== 'loading')) :
+  return useNative ? (link.import && (link.import.readyState !== 'loading')) || link.__loaded :
       link.__importParsed;
 }
 
+// TODO(sorvell): install a mutation observer to see if HTMLImports have loaded
+// this is a workaround for https://www.w3.org/Bugs/Public/show_bug.cgi?id=25007
+// and should be removed when this bug is addressed.
+if (useNative) {
+  new MutationObserver(function(mxns) {
+    for (var i=0, l=mxns.length, m; (i < l) && (m=mxns[i]); i++) {
+      if (m.addedNodes) {
+        handleImports(m.addedNodes);
+      }
+    }
+  }).observe(document.head, {childList: true});
+
+  function handleImports(nodes) {
+    for (var i=0, l=nodes.length, n; (i<l) && (n=nodes[i]); i++) {
+      if (isImport(n)) {
+        handleImport(n);  
+      }
+    }
+  }
+
+  function isImport(element) {
+    return element.localName === 'link' && element.rel === 'import';
+  }
+
+  function handleImport(element) {
+    var loaded = element.import;
+    if (loaded) {
+      markTargetLoaded({target: element});
+    } else {
+      element.addEventListener('load', markTargetLoaded);
+      element.addEventListener('error', markTargetLoaded);
+    }
+  }
+
+  function markTargetLoaded(event) {
+    event.target.__loaded = true;
+  }
+
+}
+
 // exports
 scope.hasNative = hasNative;
 scope.useNative = useNative;

diff --git a/test/html/load-404.html b/test/html/load-404.html
@@ -0,0 +1,36 @@
+<!doctype html>
+<html>
+  <head>
+    <title>load ready 404 test</title>
+    <script>
+    </script>
+    <script src="../../../tools/test/htmltest.js"></script>
+    <script src="../../../tools/test/chai/chai.js"></script>
+    <script src="../../html-imports.js"></script>
+    <link rel="import" href="imports/404-1.html">
+    <link rel="import" href="imports/404-2.html">
+    <link rel="import" href="imports/404-3.html">
+    <link rel="import" href="imports/404-4.html">
+
+  </head>
+  <body>
+    <script>
+      var loaded = false;
+      document.addEventListener('HTMLImportsLoaded', function() {
+        loaded = true;
+        check();
+      });
+
+      // wait some time and then fail if no load event is fired
+      var timeout = setTimeout(function() {
+        check();
+      }, 2000);
+
+      function check() {
+        clearTimeout(timeout);
+        chai.assert.ok(loaded, '404\'d imports are loaded');
+        done();
+      }
+    </script>
+  </body>
+</html>
diff --git a/test/js/tests.js b/test/js/tests.js
@@ -10,6 +10,7 @@ htmlSuite('HTMLImports', function() {
   htmlTest('html/style-links.html');
   htmlTest('html/style-paths.html');
   htmlTest('html/load.html');
+  htmlTest('html/load-404.html');
   htmlTest('html/currentScript.html');
   htmlTest('html/dedupe.html');
   htmlTest('html/dynamic.html');