Install barback from a hosted source in all tests.

test/run/doesnt_load_an_unnecessary_transformer_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.
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 import '../serve/utils.dart';
 
 const TRANSFORMER = """
 import 'dart:async';
 
 import 'package:barback/barback.dart';
 
 class BrokenTransformer extends Transformer {
   RewriteTransformer.asPlugin() {
     throw 'This transformer is broken!';
   }
 
   String get allowedExtensions => '.txt';
 
   void apply(Transform transform) {}
 }
 """;
 
 main() {
-  integration("doesn't load an unnecessary transformer", () {
-    d.dir(appPath, [
-      d.pubspec({
-        "name": "myapp",
-        "transformers": [
-          {"myapp/src/transformer": {r"$include": "lib/myapp.dart"}}
-        ]
-      }),
-      d.dir("lib", [
-        d.file("myapp.dart", ""),
-        d.dir("src", [d.file("transformer.dart", TRANSFORMER)])
-      ]),
-      d.dir("bin", [
-        d.file("hi.dart", "void main() => print('Hello!');")
-      ])
-    ]).create();
+   integration("doesn't load an unnecessary transformer", () {
+     serveBarback();
 
-    createLockFile('myapp', pkg: ['barback']);
+     d.dir(appPath, [
+       d.pubspec({
+         "name": "myapp",
+         "transformers": [
+           {"myapp/src/transformer": {r"$include": "lib/myapp.dart"}}
+         ],
+         "dependencies": {"barback": "any"}
+       }),
+       d.dir("lib", [
+         d.file("myapp.dart", ""),
+         d.dir("src", [d.file("transformer.dart", TRANSFORMER)])
+       ]),
+       d.dir("bin", [
+         d.file("hi.dart", "void main() => print('Hello!');")
+       ])
+     ]).create();
 
-    // This shouldn't load the transformer, since it doesn't transform
-    // anything that the entrypoint imports. If it did load the transformer,
-    // we'd know since it would throw an exception.
-    var pub = pubRun(args: ["bin/hi"]);
-    pub.stdout.expect("Hello!");
-    pub.shouldExit();
-  });
+     pubGet();
+
+     // This shouldn't load the transformer, since it doesn't transform
+     // anything that the entrypoint imports. If it did load the transformer,
+     // we'd know since it would throw an exception.
+     var pub = pubRun(args: ["bin/hi"]);
+     pub.stdout.expect("Hello!");
+     pub.shouldExit();
+   });
 }