Even easier observatory testing.

runtime/bin/vmservice/observatory/test/metrics_test.dart

-// Copyright (c) 2014, 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.
-
-library allocations_test;
-
-import 'test_helper.dart';
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
+import 'test_helper.dart';
 
-import 'dart:io';
+import 'dart:profiler';
 
-main() {
-  String script = 'metrics_script.dart';
-  var process = new TestLauncher(script);
-  process.launch().then((port) {
-    String addr = 'ws://localhost:$port/ws';
-    new WebSocketVM(new WebSocketVMTarget(addr)).get('vm')
-        .then((VM vm) => vm.isolates.first.load())
-        .then((Isolate isolate) =>
-          isolate.get('metrics').then((ServiceMap metrics) {
-            expect(metrics['type'], equals('MetricList'));
-            var members = metrics['members'];
-            expect(members, isList);
-            expect(members.length, equals(1));
-            var counter = members[0];
-            expect(counter['name'], equals('a.b.c'));
-            expect(counter['value'], equals(1234.5));
-            return isolate;
-          }))
-        .then((Isolate isolate) =>
-          isolate.get('metrics/a.b.c').then((ServiceMap counter) {
-            expect(counter['name'], equals('a.b.c'));
-            expect(counter['value'], equals(1234.5));
-            return isolate;
-          }))
-        .then((Isolate isolate) =>
-          isolate.get('metrics/a.b.c.d').then((DartError err) {
-            expect(err is DartError, isTrue);
-            return isolate;
-          }))
-        .then((Isolate isolate) => exit(0));
-  });
+void script() {
+  var counter = new Counter('a.b.c', 'description');
+  Metrics.register(counter);
+  counter.value = 1234.5;
 }
+
+var tests = [
+
+(Isolate isolate) =>
+  isolate.get('metrics').then((ServiceMap metrics) {
+    expect(metrics['type'], equals('MetricList'));
+    var members = metrics['members'];
+    expect(members, isList);
+    expect(members.length, equals(1));
+    var counter = members[0];
+    expect(counter['name'], equals('a.b.c'));
+    expect(counter['value'], equals(1234.5));
+}),
+
+(Isolate isolate) =>
+  isolate.get('metrics/a.b.c').then((ServiceMap counter) {
+    expect(counter['name'], equals('a.b.c'));
+    expect(counter['value'], equals(1234.5));
+}),
+
+(Isolate isolate) =>
+  isolate.get('metrics/a.b.d').then((DartError err) {
+    expect(err is DartError, isTrue);
+}),
+
+];
+
+main(args) => runIsolateTests(args, tests, testeeBefore: script);