Fix deferred loading with multiple apps on same page.

Even though two apps don't have to load a file twice, they still both have to initialize it.

Still missing this support for the new emitter.

BUG=
R=floitsch@google.com

Review URL: https://codereview.chromium.org//837903002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@42660 260f80e4-7a28-3924-810f-c04153c831b5

pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart

@@ -15,6 +15,7 @@ import 'package:_internal/compiler/js_lib/shared/embedded_names.dart' show
     DEFERRED_LIBRARY_URIS,
     DEFERRED_LIBRARY_HASHES,
     INITIALIZE_LOADED_HUNK,
+    IS_HUNK_INITIALIZED,
     IS_HUNK_LOADED;
 
 import '../js_emitter.dart' show NativeGenerator;

pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart

@@ -161,6 +161,7 @@ class OldEmitter implements Emitter {
   String get lazyInitializerName
       => '${namer.isolateName}.${lazyInitializerProperty}';
   String get initName => 'init';
+
   String get makeConstListProperty
       => namer.getMappedInstanceName('makeConstantList');
 
@@ -1831,23 +1832,34 @@ function(originalDescriptor, name, holder, isStatic, globalFunctionsAccess) {
   /// Emits support-code for deferred loading into [buffer].
   void emitDeferredBoilerPlate(CodeBuffer buffer,
                                Map<OutputUnit, String> deferredLoadHashes) {
-    // Function for checking if a hunk is loaded given its hash.
-    buffer.write(jsAst.prettyPrint(
-        js('# = function(hunkHash) {'
-           '  return !!$deferredInitializers[hunkHash];'
-           '}', generateEmbeddedGlobalAccess(embeddedNames.IS_HUNK_LOADED)),
+    jsAst.Statement functions = js.statement('''
+        {
+          // Function for checking if a hunk is loaded given its hash.
+          #isHunkLoaded = function(hunkHash) {
+            return !!$deferredInitializers[hunkHash];
+          };
+          #deferredInitialized = new Object(null);
+          // Function for checking if a hunk is initialized given its hash.
+          #isHunkInitialized = function(hunkHash) {
+            return #deferredInitialized[hunkHash];
+          };
+          // Function for initializing a loaded hunk, given its hash.
+          #initializeLoadedHunk = function(hunkHash) {
+            $deferredInitializers[hunkHash](
+            $globalsHolder, ${namer.currentIsolate});
+            #deferredInitialized[hunkHash] = true;
+          };
+        }
+        ''', {"isHunkLoaded": generateEmbeddedGlobalAccess(
+                  embeddedNames.IS_HUNK_LOADED),
+              "isHunkInitialized": generateEmbeddedGlobalAccess(
+                  embeddedNames.IS_HUNK_INITIALIZED),
+              "initializeLoadedHunk": generateEmbeddedGlobalAccess(
+                  embeddedNames.INITIALIZE_LOADED_HUNK),
+              "deferredInitialized": generateEmbeddedGlobalAccess(
+                  embeddedNames.DEFERRED_INITIALIZED)});
+    buffer.write(jsAst.prettyPrint(functions,
         compiler, monitor: compiler.dumpInfoTask));
-    buffer.write('$N');
-    // Function for initializing a loaded hunk, given its hash.
-    buffer.write(jsAst.prettyPrint(
-        js('# = function(hunkHash) {'
-           '  $deferredInitializers[hunkHash]('
-                '$globalsHolder, ${namer.currentIsolate})'
-           '}',
-           generateEmbeddedGlobalAccess(
-               embeddedNames.INITIALIZE_LOADED_HUNK)),
-        compiler, monitor: compiler.dumpInfoTask));
-    buffer.write('$N');
     // Write a javascript mapping from Deferred import load ids (derrived
     // from the import prefix.) to a list of lists of uris of hunks to load,
     // and a corresponding mapping to a list of hashes used by

sdk/lib/_internal/compiler/js_lib/js_helper.dart

@@ -15,6 +15,7 @@ import 'dart:_js_embedded_names' show
     DEFERRED_LIBRARY_HASHES,
     INITIALIZE_LOADED_HUNK,
     IS_HUNK_LOADED,
+    IS_HUNK_INITIALIZED,
     NATIVE_SUPERCLASS_TAG_NAME;
 
 import 'dart:collection';
@@ -3313,15 +3314,18 @@ Future<Null> loadDeferredLibrary(String loadId) {
   // The indices into `uris` and `hashes` that we want to load.
   List<int> indices = new List.generate(uris.length, (i) => i);
   var isHunkLoaded = JS_EMBEDDED_GLOBAL('', IS_HUNK_LOADED);
+  var isHunkInitialized = JS_EMBEDDED_GLOBAL('', IS_HUNK_INITIALIZED);
   // Filter away indices for hunks that have already been loaded.
   List<int> indicesToLoad = indices
       .where((int i) => !JS('bool','#(#)', isHunkLoaded, hashes[i]))
       .toList();
-  // Load the needed hunks.
+  List<int> indicesToInitialize = indices
+      .where((int i) => !JS('bool','#(#)', isHunkInitialized, hashes[i]))
+      .toList();  // Load the needed hunks.
   return Future.wait(indicesToLoad
       .map((int i) => _loadHunk(uris[i]))).then((_) {
     // Now all hunks have been loaded, we run the needed initializers.
-    for (int i in indicesToLoad) {
+    for (int i in indicesToInitialize) {
       var initializer = JS_EMBEDDED_GLOBAL('', INITIALIZE_LOADED_HUNK);
       JS('void', '#(#)', initializer, hashes[i]);
     }

sdk/lib/_internal/compiler/js_lib/shared/embedded_names.dart

@@ -32,6 +32,8 @@ const DEFERRED_LIBRARY_URIS = 'deferredLibraryUris';
 const DEFERRED_LIBRARY_HASHES = 'deferredLibraryHashes';
 const INITIALIZE_LOADED_HUNK = 'initializeLoadedHunk';
 const IS_HUNK_LOADED = 'isHunkLoaded';
+const IS_HUNK_INITIALIZED = 'isHunkInitialized';
+const DEFERRED_INITIALIZED = 'deferredInitialized';
 const CLASS_ID_EXTRACTOR = 'classIdExtractor';
 const CLASS_FIELDS_EXTRACTOR = 'classFieldsExtractor';
 const INSTANCE_FROM_CLASS_ID = "instanceFromClassId";

tests/html/deferred_multi_app.dart

@@ -0,0 +1,28 @@
+// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import "deferred_multi_app_lib.dart" deferred as lib;
+import "dart:async";
+import "dart:html";
+import "package:expect/expect.dart";
+
+main() {
+  Element state = querySelector("#state");
+  if (state.text == "1") {
+    lib.loadLibrary().then((_) {
+      var a = lib.one();
+      Expect.equals("one", a);
+      window.postMessage(a, '*');
+    });
+    state.text = "2";
+  } else {
+    new Timer(new Duration(milliseconds: 100), () {
+      lib.loadLibrary().then((_) {
+        var a = lib.two();
+        Expect.equals("two", a);
+        window.postMessage(a, '*');
+      });
+    });
+  }
+}

tests/html/deferred_multi_app_htmltest.html

@@ -0,0 +1,23 @@
+<!--
+Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+for details. All rights reserved. Use of this source code is governed by a
+BSD-style license that can be found in the LICENSE file.
+
+Test that two instances of a script does not interfere when loading the same
+deferred library.
+
+START_HTML_DART_TEST
+{
+  "scripts": ["deferred_multi_app.dart"],
+  "expectedMessages": ["one", "two"]
+}
+END_HTML_DART_TEST
+-->
+<html>
+  <body>
+    <div id="state">1</div>
+    <script>window.parent.dispatchEvent(new Event('detect_errors'));</script>
+    <script src="deferred_multi_app.dart" type="application/dart"></script>
+    <script src="deferred_multi_app.dart" type="application/dart"></script>
+  </body>
+</html>

tests/html/deferred_multi_app_lib.dart

@@ -0,0 +1,11 @@
+// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+one() {
+  return "one";
+}
+
+two() {
+  return "two";
+}

tests/html/html.status

@@ -105,6 +105,9 @@ xhr_test: Pass, Fail # Issue 11884
 [$runtime == drt || $runtime == dartium || $runtime == chrome || $runtime == chromeOnAndroid || $runtime == ContentShellOnAndroid ]
 webgl_1_test: Pass, Fail # Issue 8219
 
+[ ($compiler == none || $compiler == dart2dart) ]
+deferred_multi_app_htmltest: Fail # Issue 16603
+
 [ $compiler == none && ($runtime == drt || $runtime == dartium) && $system == windows]
 websql_test: Skip # Issue 4941: stderr contains a backtrace.