Heap snapshot visualizations

runtime/observatory/tests/service/graph_test.dart

Index: runtime/observatory/tests/service/graph_test.dart
diff --git a/runtime/observatory/tests/service/graph_test.dart b/runtime/observatory/tests/service/graph_test.dart
index 907dcd40c4b97d79bdb88a8b77eac4928a0a1241..9b0b937f2136fe788c222fc1d316ff6842b6749a 100644
--- a/runtime/observatory/tests/service/graph_test.dart
+++ b/runtime/observatory/tests/service/graph_test.dart
@@ -37,61 +37,55 @@ int fooId;
 
 var tests = [
 
-(Isolate isolate) {
-  Completer completer = new Completer();
-  isolate.vm.getEventStream('_Graph').listen((ServiceEvent event) {
-    if (event.eventType == ServiceEvent.kGraph) {
-      ReadStream reader = new ReadStream(event.data);
-      ObjectGraph graph = new ObjectGraph(reader);
-      expect(fooId, isNotNull);
-      Iterable<ObjectVertex> foos = graph.vertices.where(
-          (ObjectVertex obj) => obj.classId == fooId);
-      expect(foos.length, equals(3));
-      expect(foos.where(
-          (ObjectVertex obj) => obj.succ.length == 0).length, equals(1));
-      expect(foos.where(
-          (ObjectVertex obj) => obj.succ.length == 1).length, equals(1));
-      expect(foos.where(
-          (ObjectVertex obj) => obj.succ.length == 2).length, equals(1));
-
-      ObjectVertex bVertex = foos.where(
-          (ObjectVertex obj) => obj.succ.length == 0).first;
-      ObjectVertex aVertex = foos.where(
-          (ObjectVertex obj) => obj.succ.length == 1).first;
-      ObjectVertex rVertex = foos.where(
-          (ObjectVertex obj) => obj.succ.length == 2).first;
-
-      // TODO(koda): Check actual byte sizes.
-
-      expect(aVertex.retainedSize, equals(aVertex.shallowSize));
-      expect(bVertex.retainedSize, equals(bVertex.shallowSize));
-      expect(rVertex.retainedSize, equals(aVertex.shallowSize +
-                                          bVertex.shallowSize +
-                                          rVertex.shallowSize));
-
-      const int fixedSizeListCid = 61;
-      List<ObjectVertex> lists = new List.from(graph.vertices.where(
-          (ObjectVertex obj) => obj.classId == fixedSizeListCid));
-      expect(lists.length >= 2, isTrue);
-      // Order by decreasing retained size.
-      lists.sort((u, v) => v.retainedSize - u.retainedSize);
-      ObjectVertex first = lists[0];
-      ObjectVertex second = lists[1];
-      // Check that the short list retains more than the long list inside.
-      expect(first.succ.length, equals(2 + second.succ.length));
-      // ... and specifically, that it retains exactly itself + the long one.
-      expect(first.retainedSize,
-          equals(first.shallowSize + second.shallowSize));
-      completer.complete();
-    }
-  });
-  return isolate.rootLibrary.load().then((Library lib) {
-    expect(lib.classes.length, equals(1));
-    Class fooClass = lib.classes.first;
-    fooId = fooClass.vmCid;
-    isolate.invokeRpcNoUpgrade('requestHeapSnapshot', {});
-    return completer.future;
-  });
+(Isolate isolate) async {
+  Library lib = await isolate.rootLibrary.load();
+  expect(lib.classes.length, equals(1));
+  Class fooClass = lib.classes.first;
+  fooId = fooClass.vmCid;
+
+  HeapSnapshot snapshot = await isolate.fetchHeapSnapshot().last;
+  ObjectGraph graph = snapshot.graph;
+
+  expect(fooId, isNotNull);
+  Iterable<ObjectVertex> foos = graph.vertices.where(
+      (ObjectVertex obj) => obj.vmCid == fooId);
+  expect(foos.length, equals(3));
+  expect(foos.where((obj) => obj.successors.length == 0).length,
+         equals(1));
+  expect(foos.where((obj) => obj.successors.length == 1).length,
+         equals(1));
+  expect(foos.where((obj) => obj.successors.length == 2).length,
+         equals(1));
+
+  ObjectVertex bVertex = foos.where(
+      (ObjectVertex obj) => obj.successors.length == 0).first;
+  ObjectVertex aVertex = foos.where(
+      (ObjectVertex obj) => obj.successors.length == 1).first;
+  ObjectVertex rVertex = foos.where(
+      (ObjectVertex obj) => obj.successors.length == 2).first;
+
+  // TODO(koda): Check actual byte sizes.
+
+  expect(aVertex.retainedSize, equals(aVertex.shallowSize));
+  expect(bVertex.retainedSize, equals(bVertex.shallowSize));
+  expect(rVertex.retainedSize, equals(aVertex.shallowSize +
+                                      bVertex.shallowSize +
+                                      rVertex.shallowSize));
+
+  const int fixedSizeListCid = 61;
+  List<ObjectVertex> lists = new List.from(graph.vertices.where(
+      (ObjectVertex obj) => obj.vmCid == fixedSizeListCid));
+  expect(lists.length >= 2, isTrue);
+  // Order by decreasing retained size.
+  lists.sort((u, v) => v.retainedSize - u.retainedSize);
+  ObjectVertex first = lists[0];
+  ObjectVertex second = lists[1];
+  // Check that the short list retains more than the long list inside.
+  expect(first.successors.length,
+         equals(2 + second.successors.length));
+  // ... and specifically, that it retains exactly itself + the long one.
+  expect(first.retainedSize,
+         equals(first.shallowSize + second.shallowSize));
 },
 
 ];