From 1bd7090b73a796ef7f0692f311e7da40a9b5c99b Mon Sep 17 00:00:00 2001
From: valdrinkoshi <valdrin@google.com>
Date: Tue, 14 Feb 2017 14:05:44 -0800
Subject: [PATCH 1/4] WebComponentsReady fired once.

---
 tests/load.html         |  5 +++--
 webcomponents-loader.js | 11 +++++------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/tests/load.html b/tests/load.html
index f498d86..f5ac417 100644
--- a/tests/load.html
+++ b/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>
@@ -28,7 +29,7 @@ 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');
+          assert.equal(window.webComponentsReadyCount, 1, 'failed to fire WebComponentsReady');
           if (!window.HTMLImports.useNative) {
             assert.ok(window.importsOk, 'WebComponentsReady without HTMLImportsLoaded');
           }
diff --git a/webcomponents-loader.js b/webcomponents-loader.js
index 3d38edc..09e004f 100644
--- a/webcomponents-loader.js
+++ b/webcomponents-loader.js
@@ -59,6 +59,11 @@
   // https://github.com/webcomponents/shadycss/issues/46.
   if (!polyfills.length) {
     polyfills.push('none');
+    HTMLImports.whenReady(function() {
+      requestAnimationFrame(function() {
+        window.dispatchEvent(new CustomEvent('WebComponentsReady'));
+      })
+    });
   } else if (polyfills.length === 4) {  // hi-ce-sd-pf is actually called lite.
     polyfills = ['lite'];
   }
@@ -72,10 +77,4 @@
     newScript.src = url;
     document.head.appendChild(newScript);
   }
-
-  HTMLImports.whenReady(function() {
-    requestAnimationFrame(function() {
-      window.dispatchEvent(new CustomEvent('WebComponentsReady'));
-    })
-  });
 })();

From 6c53a012b94bee0f8bb57c77695042446ea1dd22 Mon Sep 17 00:00:00 2001
From: valdrinkoshi <valdrin@google.com>
Date: Tue, 14 Feb 2017 15:09:03 -0800
Subject: [PATCH 2/4] conditional stubbing of HTMLImports

---
 webcomponents-loader.js | 68 ++++++++++++++++++++---------------------
 1 file changed, 33 insertions(+), 35 deletions(-)

diff --git a/webcomponents-loader.js b/webcomponents-loader.js
index 09e004f..ca883b4 100644
--- a/webcomponents-loader.js
+++ b/webcomponents-loader.js
@@ -11,39 +11,31 @@
 (function() {
   // Feature detect which polyfill needs to be imported.
   let polyfills = [];
-  let useNativeImports = ('import' in document.createElement('link'));
-  if (!useNativeImports) {
-    polyfills.push('hi');
-  }
-
-  // Stub out HTMLImports if we're using native imports
-  window.HTMLImports = {
-    useNative: useNativeImports,
-    whenReady: function(callback) {
-      if (useNativeImports) {
+  if ('import' in document.createElement('link')) {
+    // Stub out HTMLImports if we're using native imports.
+    window.HTMLImports = {
+      useNative: true,
+      importForElement: function(el) {
+        return el.ownerDocument !== document ? el.ownerDocument : null;
+      },
+      whenReady: function(callback) {
         // 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() {
+        if (document.readyState === 'loading') {
+          document.addEventListener('readystatechange', 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();
+            HTMLImports.whenReady(callback);
           });
+        } else if (document.readyState === 'interactive') {
+          requestAnimationFrame(callback);
+        } else {
+          callback();
         }
-      } else {
-        window.addEventListener('HTMLImportsLoaded', callback);
       }
-    }
-  };
-
+    };
+  } else {
+    polyfills.push('hi');
+  }
   if (!('attachShadow' in Element.prototype) || (window.ShadyDOM && window.ShadyDOM.force)) {
     polyfills.push('sd');
   }
@@ -59,12 +51,7 @@
   // https://github.com/webcomponents/shadycss/issues/46.
   if (!polyfills.length) {
     polyfills.push('none');
-    HTMLImports.whenReady(function() {
-      requestAnimationFrame(function() {
-        window.dispatchEvent(new CustomEvent('WebComponentsReady'));
-      })
-    });
-  } 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'];
   }
 
@@ -73,8 +60,19 @@
     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);
   }
-})();
+  // 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') {
+    HTMLImports.whenReady(function() {
+      requestAnimationFrame(function() {
+        window.dispatchEvent(new CustomEvent('WebComponentsReady'));
+      });
+    });
+  }
+})();
\ No newline at end of file

From 544935fc2e200a407f4fd96071692eb530d44d0c Mon Sep 17 00:00:00 2001
From: valdrinkoshi <valdrin@google.com>
Date: Tue, 14 Feb 2017 15:13:54 -0800
Subject: [PATCH 3/4] add test for importForElement

---
 tests/ce-import.html | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tests/ce-import.html b/tests/ce-import.html
index 4324af1..d3de8f7 100644
--- a/tests/ce-import.html
+++ b/tests/ce-import.html
@@ -30,6 +30,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
         HTMLImports.whenReady(function() {
           assert.isTrue(xfoo.isCreated, 'element in main document, registered in dynamic import is upgraded');
           var ix = link.import.querySelector('x-foo');
+          assert.equal(HTMLImports.importForElement(ix), link.import, 'import for element should be link import');
           assert.isTrue(ix.isCreated, 'element in import, registered in dynamic import is upgraded');
           done();
         });

From 2918670bcdcd42f26d531e80f039ef5e5f150467 Mon Sep 17 00:00:00 2001
From: valdrinkoshi <valdrin@google.com>
Date: Tue, 14 Feb 2017 17:40:21 -0800
Subject: [PATCH 4/4] remove HTMLImports stub

---
 tests/ce-import-upgrade-async.html |  2 +-
 tests/ce-import.html               |  4 +---
 tests/ce-upgradedocumenttree.html  |  2 +-
 tests/load.html                    |  2 +-
 webcomponents-loader.js            | 30 +++---------------------------
 5 files changed, 7 insertions(+), 33 deletions(-)

diff --git a/tests/ce-import-upgrade-async.html b/tests/ce-import-upgrade-async.html
index a5f6460..578bc7d 100644
--- a/tests/ce-import-upgrade-async.html
+++ b/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();
diff --git a/tests/ce-import.html b/tests/ce-import.html
index d3de8f7..35f7c42 100644
--- a/tests/ce-import.html
+++ b/tests/ce-import.html
@@ -26,11 +26,9 @@ 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.equal(HTMLImports.importForElement(ix), link.import, 'import for element should be link import');
           assert.isTrue(ix.isCreated, 'element in import, registered in dynamic import is upgraded');
           done();
         });
diff --git a/tests/ce-upgradedocumenttree.html b/tests/ce-upgradedocumenttree.html
index fd3b1d5..1edf563 100644
--- a/tests/ce-upgradedocumenttree.html
+++ b/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() {
diff --git a/tests/load.html b/tests/load.html
index f5ac417..248d745 100644
--- a/tests/load.html
+++ b/tests/load.html
@@ -30,7 +30,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       suite('Loader', function() {
         test('expected boot', function() {
           assert.equal(window.webComponentsReadyCount, 1, 'failed to fire WebComponentsReady');
-          if (!window.HTMLImports.useNative) {
+          if (window.HTMLImports) {
             assert.ok(window.importsOk, 'WebComponentsReady without HTMLImportsLoaded');
           }
           assert.ok(window.importTest, 'import failed to set global value');
diff --git a/webcomponents-loader.js b/webcomponents-loader.js
index ca883b4..ccbd636 100644
--- a/webcomponents-loader.js
+++ b/webcomponents-loader.js
@@ -11,29 +11,7 @@
 (function() {
   // Feature detect which polyfill needs to be imported.
   let polyfills = [];
-  if ('import' in document.createElement('link')) {
-    // Stub out HTMLImports if we're using native imports.
-    window.HTMLImports = {
-      useNative: true,
-      importForElement: function(el) {
-        return el.ownerDocument !== document ? el.ownerDocument : null;
-      },
-      whenReady: function(callback) {
-        // 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 === 'loading') {
-          document.addEventListener('readystatechange', function once() {
-            document.removeEventListener('readystatechange', once);
-            HTMLImports.whenReady(callback);
-          });
-        } else if (document.readyState === 'interactive') {
-          requestAnimationFrame(callback);
-        } else {
-          callback();
-        }
-      }
-    };
-  } else {
+  if (!('import' in document.createElement('link'))) {
     polyfills.push('hi');
   }
   if (!('attachShadow' in Element.prototype) || (window.ShadyDOM && window.ShadyDOM.force)) {
@@ -69,10 +47,8 @@
   // is removed. Addressing this is blocked on
   // https://github.com/webcomponents/shadycss/issues/46.
   if (polyfills[0] === 'none') {
-    HTMLImports.whenReady(function() {
-      requestAnimationFrame(function() {
-        window.dispatchEvent(new CustomEvent('WebComponentsReady'));
-      });
+    requestAnimationFrame(function() {
+      window.dispatchEvent(new CustomEvent('WebComponentsReady'));
     });
   }
 })();
\ No newline at end of file