Initial isolate reload support

This is a cut of the work that Todd and I collaborated on in the reload branch.

In this CL, we've dropped the loader port hacks, in other words, on stack reloading in the standalone embedder does not work yet.

- [x] Support for hot reloading of isolate source code
- [x] Unit test harness and many tests
- [x] Service protocol and Observatory support
- [x] Product build does not include support for hot reloading.

[email protected]

Review URL: https://codereview.chromium.org/1965823002 .

Author: johnmccutchan

runtime/include/dart_api.h

@@ -2658,7 +2658,8 @@ DART_EXPORT Dart_Handle Dart_SetNativeResolver(
 typedef enum {
   Dart_kImportTag = 0,
   Dart_kSourceTag,
-  Dart_kCanonicalizeUrl
+  Dart_kCanonicalizeUrl,
+  Dart_kScriptTag,
 } Dart_LibraryTag;
 
 /* TODO(turnidge): Document. */

runtime/lib/developer.cc

@@ -18,7 +18,6 @@
 namespace dart {
 
 // Native implementations for the dart:developer library.
-
 DEFINE_NATIVE_ENTRY(Developer_debugger, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(Bool, when, arguments->NativeArgAt(0));
   GET_NATIVE_ARGUMENT(String, msg, arguments->NativeArgAt(1));

runtime/observatory/lib/src/app/application.dart

@@ -101,6 +101,10 @@ class ObservatoryApplication extends Observable {
         // Ignore for now.
         break;
 
+      case ServiceEvent.kIsolateReload:
+        notifications.add(new Notification.fromEvent(event));
+        break;
+
       case ServiceEvent.kIsolateExit:
       case ServiceEvent.kResume:
         removePauseEvents(event.isolate);

runtime/observatory/lib/src/elements/debugger.dart

@@ -902,6 +902,7 @@ class IsolateCommand extends DebuggerCommand {
   IsolateCommand(Debugger debugger) : super(debugger, 'isolate', [
     new IsolateListCommand(debugger),
     new IsolateNameCommand(debugger),
+    new IsolateReloadCommand(debugger),
   ]) {
     alias = 'i';
   }
@@ -962,10 +963,10 @@ class IsolateCommand extends DebuggerCommand {
     }
     return new Future.value(result);
   }
-  String helpShort = 'Switch the current isolate';
+  String helpShort = 'Switch, list, rename, or reload isolates';
 
   String helpLong =
-      'Switch, list, or rename isolates.\n'
+      'Switch the current isolate.\n'
       '\n'
       'Syntax: isolate <number>\n'
       '        isolate <name>\n';
@@ -1042,14 +1043,36 @@ class IsolateNameCommand extends DebuggerCommand {
     return debugger.isolate.setName(args[0]);
   }
 
-  String helpShort = 'Rename an isolate';
+  String helpShort = 'Rename the current isolate';
 
   String helpLong =
-      'Rename an isolate.\n'
+      'Rename the current isolate.\n'
       '\n'
       'Syntax: isolate name <name>\n';
 }
 
+class IsolateReloadCommand extends DebuggerCommand {
+  IsolateReloadCommand(Debugger debugger) : super(debugger, 'reload', []);
+
+  Future run(List<String> args) async {
+    if (debugger.isolate == null) {
+      debugger.console.print('There is no current vm');
+      return;
+    }
+
+    await debugger.isolate.reloadSources();
+
+    debugger.console.print('Isolate reloading....');
+  }
+
+  String helpShort = 'Reload the sources for the current isolate.';
+
+  String helpLong =
+      'Reload the sources for the current isolate.\n'
+      '\n'
+      'Syntax: reload\n';
+}
+
 class InfoCommand extends DebuggerCommand {
   InfoCommand(Debugger debugger) : super(debugger, 'info', [
       new InfoBreakpointsCommand(debugger),
@@ -1650,6 +1673,15 @@ class ObservatoryDebugger extends Debugger {
         console.print("Isolate ${iso.number} renamed to '${iso.name}'");
         break;
 
+      case ServiceEvent.kIsolateReload:
+        var reloadError = event.reloadError;
+        if (reloadError != null) {
+          console.print('Isolate reload failed: ${event.reloadError}');
+        } else {
+          console.print('Isolate reloaded.');
+        }
+        break;
+
       case ServiceEvent.kPauseStart:
       case ServiceEvent.kPauseExit:
       case ServiceEvent.kPauseBreakpoint:

runtime/observatory/lib/src/elements/isolate_view.dart

@@ -33,4 +33,8 @@ class IsolateViewElement extends ObservatoryElement {
       await isolate.topFrame.function.load();
     }
   }
+
+  Future reloadSources() {
+    return isolate.reloadSources();
+  }
 }

runtime/observatory/lib/src/elements/isolate_view.html

@@ -94,7 +94,16 @@ <h1>isolate '{{ isolate.name }}'</h1>
               <div class="memberName">service protocol extensions</div>
               <div class="memberValue">{{ isolate.extensionRPCs }}</div>
             </div>
+
+            <div class="memberItem">
+              <div class="memberName">
+                <action-link callback="{{ reloadSources }}"
+                             label="reload sources">
+                </action-link>
+              </div>
+            </div>
           </div>
+
         </div>
       </div>
     </div>

runtime/observatory/lib/src/elements/nav_bar.html

@@ -298,6 +298,10 @@
         animation: fadein 1s;
       }
 
+      .wide-item {
+        width: 50vw;
+      }
+
       @keyframes fadein {
         from { opacity: 0; }
         to   { opacity: 1; }
@@ -328,6 +332,9 @@
       a.boxclose:hover {
         background: rgba(255,255,255,0.5);
       }
+      .error {
+        white-space: pre;
+      }
     </style>
     <template if="{{ event != null }}">
       <template if="{{ notifyOnPause && event.isPauseEvent }}">
@@ -372,6 +379,21 @@
           <a class="boxclose" on-click="{{ closeItem }}">&times;</a>
         </div>
       </template>
+      <template if="{{ event.kind == 'IsolateReload' }}">
+        <div class="wide-item item">
+          Isolate reload
+          <template if="{{ event.reloadError != null }}">
+            failed:
+            <br>
+            <br>
+            <div class="indent error">{{ event.reloadError.message.toString() }}</div><br>
+          </template>
+          <template if="{{ event.reloadError == null }}">
+            succeeded
+          </template>
+          <a class="boxclose" on-click="{{ closeItem }}">&times;</a>
+        </div>
+      </template>
     </template>
   </template>
 </polymer-element>

runtime/observatory/lib/src/elements/script_view.html

@@ -21,6 +21,13 @@ <h1>script {{ script.name }}</h1>
     <object-common object="{{ script }}"></object-common>
     <br>
 
+    <div class="memberList">
+      <div class="memberItem">
+        <div class="memberName">loaded at</div>
+        <div class="memberValue">{{ script.loadTime.toString() }}</div>
+      </div>
+    </div>
+
     <hr>
     <script-inset id="scriptInset" script="{{ script }}"
                   currentPos="{{ app.locationManager.internalArguments['pos'] | parseInt }}">

runtime/observatory/lib/src/service/object.dart

@@ -42,6 +42,7 @@ class ServerRpcException extends RpcException {
   static const kStreamNotSubscribed     = 104;
   static const kIsolateMustBeRunnable   = 105;
   static const kIsolateMustBePaused     = 106;
+  static const kIsolateIsReloading      = 107;
 
   int code;
   Map data;
@@ -1149,6 +1150,7 @@ class Isolate extends ServiceObjectOwner {
   @observable bool loading = true;
   @observable bool runnable = false;
   @observable bool ioEnabled = false;
+  @observable bool reloading = false;
 
   final List<String> extensionRPCs = new List<String>();
 
@@ -1192,6 +1194,22 @@ class Isolate extends ServiceObjectOwner {
     return invokeRpc('getSourceReport', params);
   }
 
+  Future<ServiceMap> reloadSources() {
+    return invokeRpc('_reloadSources', {}).then((_) {
+      reloading = true;
+    });
+  }
+
+  void _handleIsolateReloadEvent(ServiceEvent event) {
+    reloading = false;
+    if (event.reloadError != null) {
+      // Failure.
+      print('Reload failed: ${event.reloadError}');
+    } else {
+      _cache.clear();
+    }
+  }
+
   /// Fetches and builds the class hierarchy for this isolate. Returns the
   /// Object class object.
   Future<Class> getClassHierarchy() {
@@ -1499,7 +1517,9 @@ class Isolate extends ServiceObjectOwner {
       case ServiceEvent.kInspect:
         // Handled elsewhere.
         break;
-
+      case ServiceEvent.kIsolateReload:
+        _handleIsolateReloadEvent(event);
+        break;
       case ServiceEvent.kBreakpointAdded:
         _addBreakpoint(event.breakpoint);
         break;
@@ -1823,6 +1843,7 @@ class ServiceEvent extends ServiceObject {
   static const kIsolateRunnable        = 'IsolateRunnable';
   static const kIsolateExit            = 'IsolateExit';
   static const kIsolateUpdate          = 'IsolateUpdate';
+  static const kIsolateReload          = 'IsolateReload';
   static const kServiceExtensionAdded  = 'ServiceExtensionAdded';
   static const kPauseStart             = 'PauseStart';
   static const kPauseExit              = 'PauseExit';
@@ -1854,6 +1875,7 @@ class ServiceEvent extends ServiceObject {
   @observable Frame topFrame;
   @observable String extensionRPC;
   @observable Instance exception;
+  @observable Instance reloadError;
   @observable bool atAsyncSuspension;
   @observable ServiceObject inspectee;
   @observable ByteData data;
@@ -1925,6 +1947,7 @@ class ServiceEvent extends ServiceObject {
     if (map['count'] != null) {
       count = map['count'];
     }
+    reloadError = map['reloadError'];
     if (map['_debuggerSettings'] != null &&
         map['_debuggerSettings']['_exceptions'] != null) {
       exceptions = map['_debuggerSettings']['_exceptions'];
@@ -2857,6 +2880,7 @@ class Script extends HeapObject {
   final lines = new ObservableList<ScriptLine>();
   @observable String uri;
   @observable String kind;
+  @observable DateTime loadTime;
   @observable int firstTokenPos;
   @observable int lastTokenPos;
   @observable int lineOffset;
@@ -2959,6 +2983,8 @@ class Script extends HeapObject {
       return;
     }
     _loaded = true;
+    int loadTimeMillis = map['_loadTime'];
+    loadTime = new DateTime.fromMillisecondsSinceEpoch(loadTimeMillis);
     lineOffset = map['lineOffset'];
     columnOffset = map['columnOffset'];
     _parseTokenPosTable(map['tokenPosTable']);

runtime/tests/vm/vm.status

@@ -2,6 +2,13 @@
 # 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.
 
+cc/IsolateReload_PendingUnqualifiedCall_InstanceToStatic: Fail, Crash
+cc/IsolateReload_PendingUnqualifiedCall_StaticToInstance: Fail, Crash
+cc/IsolateReload_PendingConstructorCall_AbstractToConcrete: Fail, Crash
+cc/IsolateReload_PendingConstructorCall_ConcreteToAbstract: Fail, Crash
+cc/IsolateReload_PendingStaticCall_DefinedToNSM: Fail, Crash
+cc/IsolateReload_PendingStaticCall_NSMToDefined: Fail, Crash
+
 # These tests are expected to crash on all platforms.
 cc/ArrayNew_Overflow_Crash: Crash, Timeout
 cc/AllocGeneric_Overflow: Crash, Timeout