IE11 now uses synchronous loading of script instead of async with preloading. (#13956)

Change-Id: Ia61d672a55f69326b37420305f0108f2d7443b70

2 files changed, 50 insertions, 5 deletions

diff --git a/client/src/com/vaadin/client/ApplicationConnection.java b/client/src/com/vaadin/client/ApplicationConnection.java
index 50f22edf81..c39beffd87 100644
--- a/client/src/com/vaadin/client/ApplicationConnection.java
+++ b/client/src/com/vaadin/client/ApplicationConnection.java
@@ -66,7 +66,6 @@ import com.google.gwt.user.client.Window.ClosingHandler;
 import com.google.gwt.user.client.ui.HasWidgets;
 import com.google.gwt.user.client.ui.Widget;
 import com.vaadin.client.ApplicationConfiguration.ErrorMessage;
-import com.vaadin.client.ApplicationConnection.ApplicationStoppedEvent;
 import com.vaadin.client.ResourceLoader.ResourceLoadEvent;
 import com.vaadin.client.ResourceLoader.ResourceLoadListener;
 import com.vaadin.client.communication.HasJavaScriptConnectorHelper;
@@ -2499,10 +2498,17 @@ public class ApplicationConnection implements HasHandlers {
         ApplicationConfiguration.startDependencyLoading();
         loader.loadScript(url, resourceLoadListener);
 
-        // Preload all remaining
-        for (int i = 0; i < dependencies.length(); i++) {
-            String preloadUrl = translateVaadinUri(dependencies.get(i));
-            loader.preloadResource(preloadUrl, null);
+        if (ResourceLoader.supportsInOrderScriptExecution()) {
+            for (int i = 0; i < dependencies.length(); i++) {
+                String preloadUrl = translateVaadinUri(dependencies.get(i));
+                loader.loadScript(preloadUrl, null);
+            }
+        } else {
+            // Preload all remaining
+            for (int i = 0; i < dependencies.length(); i++) {
+                String preloadUrl = translateVaadinUri(dependencies.get(i));
+                loader.preloadResource(preloadUrl, null);
+            }
         }
     }
 
diff --git a/client/src/com/vaadin/client/ResourceLoader.java b/client/src/com/vaadin/client/ResourceLoader.java
index 59ebd797d1..e88def1a72 100644
--- a/client/src/com/vaadin/client/ResourceLoader.java
+++ b/client/src/com/vaadin/client/ResourceLoader.java
@@ -204,6 +204,26 @@ public class ResourceLoader {
      */
     public void loadScript(final String scriptUrl,
             final ResourceLoadListener resourceLoadListener) {
+        loadScript(scriptUrl, resourceLoadListener,
+                !supportsInOrderScriptExecution());
+    }
+
+    /**
+     * Load a script and notify a listener when the script is loaded. Calling
+     * this method when the script is currently loading or already loaded
+     * doesn't cause the script to be loaded again, but the listener will still
+     * be notified when appropriate.
+     * 
+     * 
+     * @param scriptUrl
+     *            url of script to load
+     * @param resourceLoadListener
+     *            listener to notify when script is loaded
+     * @param async
+     *            What mode the script.async attribute should be set to
+     */
+    public void loadScript(final String scriptUrl,
+            final ResourceLoadListener resourceLoadListener, boolean async) {
         final String url = Util.getAbsoluteUrl(scriptUrl);
         ResourceLoadEvent event = new ResourceLoadEvent(this, url, false);
         if (loadedResources.contains(url)) {
@@ -236,6 +256,9 @@ public class ResourceLoader {
             ScriptElement scriptTag = Document.get().createScriptElement();
             scriptTag.setSrc(url);
             scriptTag.setType("text/javascript");
+
+            scriptTag.setPropertyBoolean("async", async);
+
             addOnloadHandler(scriptTag, new ResourceLoadListener() {
                 @Override
                 public void onLoad(ResourceLoadEvent event) {
@@ -252,6 +275,17 @@ public class ResourceLoader {
     }
 
     /**
+     * The current browser supports script.async='false' for maintaining
+     * execution order for dynamically-added scripts.
+     * 
+     * @return Browser supports script.async='false'
+     */
+    public static boolean supportsInOrderScriptExecution() {
+        return BrowserInfo.get().isIE()
+                && BrowserInfo.get().getBrowserMajorVersion() >= 11;
+    }
+
+    /**
      * Download a resource and notify a listener when the resource is loaded
      * without attempting to interpret the resource. When a resource has been
      * preloaded, it will be present in the browser's cache (provided the HTTP
@@ -316,6 +350,11 @@ public class ResourceLoader {
          *  XHR not tested - should work, probably causes other issues
          -*/
         if (BrowserInfo.get().isIE()) {
+            // If ie11+ for some reason gets a preload request
+            if (BrowserInfo.get().getBrowserMajorVersion() >= 11) {
+                throw new RuntimeException(
+                        "Browser doesn't support preloading with text/cache");
+            }
             ScriptElement element = Document.get().createScriptElement();
             element.setSrc(url);
             element.setType("text/cache");