Merge pull request #688 from webcomponents/no-double-wcready

Fire WebComponentsReady once. Remove HTMLImports stub

tests/ce-import-upgrade-async.html

@@ -26,7 +26,7 @@
           // order expected
           assert.deepEqual(a1DocsList, ['a1-instance.html', 'a1-reference.html']);
           // style applied at upgrade time
-          if (!HTMLImports.useNative) {
+          if (window.HTMLImports) {
             assert.isTrue(styleAppliedToDocument);
           }
           done();

tests/ce-import.html

@@ -26,8 +26,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
         link.rel = 'import';
         link.href = 'imports/element-import.html';
         document.head.appendChild(link);
-
-        HTMLImports.whenReady(function() {
+        link.addEventListener('load', function() {
           assert.isTrue(xfoo.isCreated, 'element in main document, registered in dynamic import is upgraded');
           var ix = link.import.querySelector('x-foo');
           assert.isTrue(ix.isCreated, 'element in import, registered in dynamic import is upgraded');

tests/ce-upgradedocumenttree.html

@@ -38,7 +38,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       }
 
       test('upgraded document tree', function(done) {
-        if (CustomElements.useNative || HTMLImports.useNative) {
+        if (CustomElements.useNative || !window.HTMLImports) {
           return done();
         } else {
           window.addEventListener('WebComponentsReady', function() {

tests/load.html

@@ -16,8 +16,9 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       window.addEventListener('HTMLImportsLoaded', function() {
         window.importsOk = true;
       });
+      window.webComponentsReadyCount = 0;
       window.addEventListener('WebComponentsReady', function() {
-        window.webComponentsReady = true;
+        window.webComponentsReadyCount++;
       });
     </script>
     <script src="../webcomponents-loader.js"></script>
@@ -28,8 +29,8 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
     <script>
       suite('Loader', function() {
         test('expected boot', function() {
-          assert.ok(window.webComponentsReady, 'failed to fire WebComponentsReady');
-          if (!window.HTMLImports.useNative) {
+          assert.equal(window.webComponentsReadyCount, 1, 'failed to fire WebComponentsReady');
+          if (window.HTMLImports) {
             assert.ok(window.importsOk, 'WebComponentsReady without HTMLImportsLoaded');
           }
           assert.ok(window.importTest, 'import failed to set global value');

webcomponents-loader.js

@@ -11,39 +11,9 @@
 (function() {
   // Feature detect which polyfill needs to be imported.
   let polyfills = [];
-  let useNativeImports = ('import' in document.createElement('link'));
-  if (!useNativeImports) {
+  if (!('import' in document.createElement('link'))) {
     polyfills.push('hi');
   }
-
-  // Stub out HTMLImports if we're using native imports
-  window.HTMLImports = {
-    useNative: useNativeImports,
-    whenReady: function(callback) {
-      if (useNativeImports) {
-        // When native imports boot, the are "ready" the first rAF after
-        // the document becomes interactive, so wait for the correct state change.
-        if (document.readyState !== 'interactive') {
-          function once() {
-            document.removeEventListener('readystatechange', once);
-            window.HTMLImports.whenReady(callback);
-          }
-          document.addEventListener('readystatechange', once);
-        } else {
-          // TODO(sorvell): Ideally `whenReady` should return synchronously
-          // when imports are not pending but this would require a more
-          // robust implementation that should probably be a small complementary
-          // library available via the html-imports polyfill.
-          requestAnimationFrame(function() {
-            callback();
-          });
-        }
-      } else {
-        window.addEventListener('HTMLImportsLoaded', callback);
-      }
-    }
-  };
-
   if (!('attachShadow' in Element.prototype) || (window.ShadyDOM && window.ShadyDOM.force)) {
     polyfills.push('sd');
   }
@@ -59,7 +29,7 @@
   // https://github.com/webcomponents/shadycss/issues/46.
   if (!polyfills.length) {
     polyfills.push('none');
-  } else if (polyfills.length === 4) {  // hi-ce-sd-pf is actually called lite.
+  } else if (polyfills.length === 4) { // hi-ce-sd-pf is actually called lite.
     polyfills = ['lite'];
   }
 
@@ -68,14 +38,17 @@
     let newScript = document.createElement('script');
     // Load it from the right place.
     var url = script.src.replace(
-        'webcomponents-loader.js', `webcomponents-${polyfills.join('-')}.js`);
+      'webcomponents-loader.js', `webcomponents-${polyfills.join('-')}.js`);
     newScript.src = url;
     document.head.appendChild(newScript);
   }
-
-  HTMLImports.whenReady(function() {
+  // Ensure `WebComponentsReady` is fired also when there are no polyfills loaded.
+  // TODO(valdrin): only check for `!polyfills.length` once 'none' bundle
+  // is removed. Addressing this is blocked on
+  // https://github.com/webcomponents/shadycss/issues/46.
+  if (polyfills[0] === 'none') {
     requestAnimationFrame(function() {
       window.dispatchEvent(new CustomEvent('WebComponentsReady'));
-    })
-  });
-})();
+    });
+  }
+})();