diff --git a/utils/tests/pub/pub_test.dart b/utils/tests/pub/pub_test.dart
index 952455d0597..26f71922b15 100644
--- a/utils/tests/pub/pub_test.dart
+++ b/utils/tests/pub/pub_test.dart
@@ -93,11 +93,15 @@ installCommand() {
   test('checks out a package from the SDK', () {
     dir(sdkPath, [
       file('revision', '1234'),
-      dir('pkg', [packageDir("foo", "0.0.1234")])
+      dir('pkg', [
+        dir('foo', [
+          file('foo.dart', 'main() => "foo";')
+        ])
+      ])
     ]).scheduleCreate();
 
     dir(appPath, [
-      pubspec({"dependencies": {"foo": null}})
+      file('pubspec.yaml', 'dependencies:\n  foo:')
     ]).scheduleCreate();
 
     schedulePub(args: ['install'],
@@ -105,7 +109,11 @@ installCommand() {
         Dependencies installed!
         ''');
 
-    packagesDir({"foo": "0.0.1234"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => "foo";')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
@@ -117,15 +125,27 @@ installCommand() {
       file('foo.dart', 'main() => "foo";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
     dir(cachePath, [
       dir('git', [
-        dir('cache', [gitPackageCacheDir('foo')]),
-        gitPackageCacheDir('foo')
+        dir('cache', [
+          dir(new RegExp(@'foo-[a-f0-9]+'), [
+            file('foo.dart', 'main() => "foo";')
+          ])
+        ]),
+        dir(new RegExp(@'foo-[a-f0-9]+'), [
+          file('foo.dart', 'main() => "foo";')
+        ])
       ])
     ]).scheduleValidate();
 
@@ -143,14 +163,24 @@ installCommand() {
 
     git('foo.git', [
       file('foo.dart', 'main() => "foo";'),
-      appPubspec([{"git": "../bar.git"}])
+      file('pubspec.yaml', '''
+dependencies:
+  bar:
+    git: ../bar.git
+''')
     ]).scheduleCreate();
 
     git('bar.git', [
       file('bar.dart', 'main() => "bar";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp("Dependencies installed!\$"));
@@ -158,11 +188,19 @@ installCommand() {
     dir(cachePath, [
       dir('git', [
         dir('cache', [
-          gitPackageCacheDir('foo'),
-          gitPackageCacheDir('bar')
+          dir(new RegExp(@'foo-[a-f0-9]+'), [
+            file('foo.dart', 'main() => "foo";')
+          ]),
+          dir(new RegExp(@'bar-[a-f0-9]+'), [
+            file('bar.dart', 'main() => "bar";')
+          ])
         ]),
-        gitPackageCacheDir('foo'),
-        gitPackageCacheDir('bar')
+        dir(new RegExp(@'foo-[a-f0-9]+'), [
+          file('foo.dart', 'main() => "foo";')
+        ]),
+        dir(new RegExp(@'bar-[a-f0-9]+'), [
+          file('bar.dart', 'main() => "bar";')
+        ])
       ])
     ]).scheduleValidate();
 
@@ -185,15 +223,27 @@ installCommand() {
       file('foo.dart', 'main() => "foo";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
     dir(cachePath, [
       dir('git', [
-        dir('cache', [gitPackageCacheDir('foo')]),
-        gitPackageCacheDir('foo')
+        dir('cache', [
+          dir(new RegExp(@'foo-[a-f0-9]+'), [
+            file('foo.dart', 'main() => "foo";')
+          ])
+        ]),
+        dir(new RegExp(@'foo-[a-f0-9]+'), [
+          file('foo.dart', 'main() => "foo";')
+        ])
       ])
     ]).scheduleValidate();
 
@@ -218,9 +268,17 @@ installCommand() {
     // git/cache directory but create a new git/ directory.
     dir(cachePath, [
       dir('git', [
-        dir('cache', [gitPackageCacheDir('foo', 2)]),
-        gitPackageCacheDir('foo'),
-        gitPackageCacheDir('foo', 2)
+        dir('cache', [
+          dir(new RegExp(@'foo-[a-f0-9]+'), [
+            file('foo.dart', 'main() => "foo 2";')
+          ])
+        ]),
+        dir(new RegExp(@'foo-[a-f0-9]+'), [
+          file('foo.dart', 'main() => "foo";')
+        ]),
+        dir(new RegExp(@'foo-[a-f0-9]+'), [
+          file('foo.dart', 'main() => "foo 2";')
+        ])
       ])
     ]).scheduleValidate();
 
@@ -240,15 +298,27 @@ installCommand() {
       file('foo.dart', 'main() => "foo";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
     dir(cachePath, [
       dir('git', [
-        dir('cache', [gitPackageCacheDir('foo')]),
-        gitPackageCacheDir('foo')
+        dir('cache', [
+          dir(new RegExp(@'foo-[a-f0-9]+'), [
+            file('foo.dart', 'main() => "foo";')
+          ])
+        ]),
+        dir(new RegExp(@'foo-[a-f0-9]+'), [
+          file('foo.dart', 'main() => "foo";')
+        ])
       ])
     ]).scheduleValidate();
 
@@ -276,13 +346,23 @@ installCommand() {
       file('foo.dart', 'main() => "foo 1";')
     ]);
     repo.scheduleCreate();
-    var commit = repo.revParse('HEAD');
+    var commitFuture = repo.revParse('HEAD');
 
     git('foo.git', [
       file('foo.dart', 'main() => "foo 2";')
     ]).scheduleCommit();
 
-    appDir([{"git": {"url": "../foo.git", "ref": commit}}]).scheduleCreate();
+    dir(appPath, [
+      async(commitFuture.transform((commit) {
+        return file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git:
+      url: ../foo.git
+      ref: $commit
+''');
+      }))
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
@@ -297,63 +377,210 @@ installCommand() {
   });
 
   test('checks out a package from a pub server', () {
-    servePackages("localhost", 3123, [package("foo", "1.2.3")]);
+    servePackages("localhost", 3123, ['{name: foo, version: 1.2.3}']);
 
-    appDir([dependency("foo", "1.2.3")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo:
+      name: foo
+      url: http://localhost:3123
+    version: 1.2.3
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp("Dependencies installed!\$"));
 
-    cacheDir({"foo": "1.2.3"}).scheduleValidate();
-    packagesDir({"foo": "1.2.3"}).scheduleValidate();
+    dir(cachePath, [
+      dir('repo', [
+        dir('localhost%583123', [
+          dir('foo-1.2.3', [
+            file('pubspec.yaml', '{name: foo, version: 1.2.3}'),
+            file('foo.dart', 'main() => print("foo 1.2.3");')
+          ])
+        ])
+      ])
+    ]).scheduleValidate();
+
+    dir(packagesPath, [
+      dir('foo', [
+        file('pubspec.yaml', '{name: foo, version: 1.2.3}'),
+        file('foo.dart', 'main() => print("foo 1.2.3");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
 
   test('checks out packages transitively from a pub server', () {
     servePackages("localhost", 3123, [
-      package("foo", "1.2.3", [dependency("bar", "2.0.4")]),
-      package("bar", "2.0.3"),
-      package("bar", "2.0.4"),
-      package("bar", "2.0.5")
+      '''
+name: foo
+version: 1.2.3
+dependencies:
+  bar:
+    repo: {name: bar, url: http://localhost:3123}
+    version: 2.0.4
+''',
+      '{name: bar, version: 2.0.3}',
+      '{name: bar, version: 2.0.4}',
+      '{name: bar, version: 2.0.5}',
     ]);
 
-    appDir([dependency("foo", "1.2.3")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo:
+      name: foo
+      url: http://localhost:3123
+    version: 1.2.3
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp("Dependencies installed!\$"));
 
-    cacheDir({"foo": "1.2.3", "bar": "2.0.4"}).scheduleValidate();
-    packagesDir({"foo": "1.2.3", "bar": "2.0.4"}).scheduleValidate();
+    dir(cachePath, [
+      dir('repo', [
+        dir('localhost%583123', [
+          dir('foo-1.2.3', [
+            file('pubspec.yaml', '''
+name: foo
+version: 1.2.3
+dependencies:
+  bar:
+    repo: {name: bar, url: http://localhost:3123}
+    version: 2.0.4
+'''),
+            file('foo.dart', 'main() => print("foo 1.2.3");')
+          ]),
+          dir('bar-2.0.4', [
+            file('pubspec.yaml', '{name: bar, version: 2.0.4}'),
+            file('bar.dart', 'main() => print("bar 2.0.4");')
+          ])
+        ])
+      ])
+    ]).scheduleValidate();
+
+    dir(packagesPath, [
+      dir('foo', [
+            file('pubspec.yaml', '''
+name: foo
+version: 1.2.3
+dependencies:
+  bar:
+    repo: {name: bar, url: http://localhost:3123}
+    version: 2.0.4
+'''),
+        file('foo.dart', 'main() => print("foo 1.2.3");')
+      ]),
+      dir('bar', [
+        file('pubspec.yaml', '{name: bar, version: 2.0.4}'),
+        file('bar.dart', 'main() => print("bar 2.0.4");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
 
   test('resolves version constraints from a pub server', () {
     servePackages("localhost", 3123, [
-      package("foo", "1.2.3", [dependency("baz", ">=2.0.0")]),
-      package("bar", "2.3.4", [dependency("baz", "<3.0.0")]),
-      package("baz", "2.0.3"),
-      package("baz", "2.0.4"),
-      package("baz", "3.0.1")
+      '''
+name: foo
+version: 1.2.3
+dependencies:
+  baz:
+    repo: {name: baz, url: http://localhost:3123}
+    version: ">=2.0.0"
+''',
+      '''
+name: bar
+version: 2.3.4
+dependencies:
+  baz:
+    repo: {name: baz, url: http://localhost:3123}
+    version: "<3.0.0"
+''',
+      '{name: baz, version: 2.0.3}',
+      '{name: baz, version: 2.0.4}',
+      '{name: baz, version: 3.0.1}',
     ]);
 
-    appDir([dependency("foo"), dependency("bar")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo: {repo: {name: foo, url: http://localhost:3123}}
+  bar: {repo: {name: bar, url: http://localhost:3123}}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp("Dependencies installed!\$"));
 
-    cacheDir({
-      "foo": "1.2.3",
-      "bar": "2.3.4",
-      "baz": "2.0.4"
-    }).scheduleValidate();
+    dir(cachePath, [
+      dir('repo', [
+        dir('localhost%583123', [
+          dir('foo-1.2.3', [
+            file('pubspec.yaml', '''
+name: foo
+version: 1.2.3
+dependencies:
+  baz:
+    repo: {name: baz, url: http://localhost:3123}
+    version: ">=2.0.0"
+'''),
+            file('foo.dart', 'main() => print("foo 1.2.3");')
+          ]),
+          dir('bar-2.3.4', [
+            file('pubspec.yaml', '''
+name: bar
+version: 2.3.4
+dependencies:
+  baz:
+    repo: {name: baz, url: http://localhost:3123}
+    version: "<3.0.0"
+'''),
+            file('bar.dart', 'main() => print("bar 2.3.4");')
+          ]),
+          dir('baz-2.0.4', [
+            file('pubspec.yaml', '{name: baz, version: 2.0.4}'),
+            file('baz.dart', 'main() => print("baz 2.0.4");')
+          ])
+        ])
+      ])
+    ]).scheduleValidate();
 
-    packagesDir({
-      "foo": "1.2.3",
-      "bar": "2.3.4",
-      "baz": "2.0.4"
-    }).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('pubspec.yaml', '''
+name: foo
+version: 1.2.3
+dependencies:
+  baz:
+    repo: {name: baz, url: http://localhost:3123}
+    version: ">=2.0.0"
+'''),
+        file('foo.dart', 'main() => print("foo 1.2.3");')
+      ]),
+      dir('bar', [
+        file('pubspec.yaml', '''
+name: bar
+version: 2.3.4
+dependencies:
+  baz:
+    repo: {name: baz, url: http://localhost:3123}
+    version: "<3.0.0"
+'''),
+        file('bar.dart', 'main() => print("bar 2.3.4");')
+      ]),
+      dir('baz', [
+        file('pubspec.yaml', '{name: baz, version: 2.0.4}'),
+        file('baz.dart', 'main() => print("baz 2.0.4");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
@@ -365,7 +592,13 @@ installCommand() {
       file('foo.dart', 'main() => "foo";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     // This install should lock the foo.git dependency to the current revision.
     schedulePub(args: ['install'],
@@ -404,7 +637,13 @@ installCommand() {
       file('foo.dart', 'main() => "foo";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
@@ -417,10 +656,17 @@ installCommand() {
 
     git('foo.git', [
       file('foo.dart', 'main() => "foo 1.0.0";'),
-      libPubspec("foo", "1.0.0")
+      file('pubspec.yaml', 'version: 1.0.0')
     ]).scheduleCommit();
 
-    appDir([{"git": "../foo.git", "version": ">=1.0.0"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+    version: ">=1.0.0"
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
@@ -440,10 +686,16 @@ installCommand() {
 
     git('foo.git', [
       file('foo.dart', 'main() => "foo 1.0.0";'),
-      libPubspec("foo", "1.0.0")
+      file('pubspec.yaml', 'version: 1.0.0')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
@@ -456,10 +708,17 @@ installCommand() {
 
     git('foo.git', [
       file('foo.dart', 'main() => "foo 1.0.1";'),
-      libPubspec("foo", "1.0.1")
+      file('pubspec.yaml', 'version: 1.0.1')
     ]).scheduleCommit();
 
-    appDir([{"git": "../foo.git", "version": ">=1.0.0"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+    version: ">=1.0.0"
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
@@ -474,82 +733,138 @@ installCommand() {
   });
 
   test('keeps a pub server package locked to the version in the lockfile', () {
-    servePackages("localhost", 3123, [package("foo", "1.0.0")]);
+    servePackages("localhost", 3123, ['{name: foo, version: 1.0.0}']);
 
-    appDir([dependency("foo")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     // This install should lock the foo dependency to version 1.0.0.
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({"foo": "1.0.0"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     // Delete the packages path to simulate a new checkout of the application.
     dir(packagesPath).scheduleDelete();
 
     // Start serving a newer package as well.
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0"),
-      package("foo", "1.0.1")
+      '{name: foo, version: 1.0.0}',
+      '{name: foo, version: 1.0.1}'
     ]);
 
     // This install shouldn't update the foo dependency due to the lockfile.
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({"foo": "1.0.0"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
 
   test('updates a locked pub server package with a new incompatible '
       'constraint', () {
-    servePackages("localhost", 3123, [package("foo", "1.0.0")]);
+    servePackages("localhost", 3123, ['{name: foo, version: 1.0.0}']);
 
-    appDir([dependency("foo")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({"foo": "1.0.0"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0"),
-      package("foo", "1.0.1")
+      '{name: foo, version: 1.0.0}',
+      '{name: foo, version: 1.0.1}'
     ]);
 
-    appDir([dependency("foo", ">1.0.0")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+    version: ">1.0.0"
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({"foo": "1.0.1"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.1");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
 
   test("doesn't update a locked pub server package with a new compatible "
       "constraint", () {
-    servePackages("localhost", 3123, [package("foo", "1.0.0")]);
+    servePackages("localhost", 3123, ['{name: foo, version: 1.0.0}']);
 
-    appDir([dependency("foo")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({"foo": "1.0.0"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0"),
-      package("foo", "1.0.1")
+      '{name: foo, version: 1.0.0}',
+      '{name: foo, version: 1.0.1}'
     ]);
 
-    appDir([dependency("foo", ">=1.0.0")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+    version: ">=1.0.0"
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({"foo": "1.0.0"}).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
@@ -557,52 +872,157 @@ installCommand() {
   test("unlocks dependencies if necessary to ensure that a new dependency "
       "is satisfied", () {
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0", [dependency("bar", "<2.0.0")]),
-      package("bar", "1.0.0", [dependency("baz", "<2.0.0")]),
-      package("baz", "1.0.0", [dependency("qux", "<2.0.0")]),
-      package("qux", "1.0.0")
-    ]);
+      '''
+name: foo
+version: 1.0.0
+dependencies:
+  bar:
+    version: "<2.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+      '''
+name: bar
+version: 1.0.0
+dependencies:
+  baz:
+    version: "<2.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''',
+      '''
+name: baz
+version: 1.0.0
+dependencies:
+  qux:
+    version: "<2.0.0"
+    repo: {name: qux, url: http://localhost:3123}
+''',
+    '''
+name: qux
+version: 1.0.0
+''']);
 
-    appDir([dependency("foo")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({
-      "foo": "1.0.0",
-      "bar": "1.0.0",
-      "baz": "1.0.0",
-      "qux": "1.0.0"
-    }).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ]),
+      dir('bar', [
+        file('bar.dart', 'main() => print("bar 1.0.0");')
+      ]),
+      dir('baz', [
+        file('baz.dart', 'main() => print("baz 1.0.0");')
+      ]),
+      dir('qux', [
+        file('qux.dart', 'main() => print("qux 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0", [dependency("bar", "<2.0.0")]),
-      package("foo", "2.0.0", [dependency("bar", "<3.0.0")]),
+      '''
+name: foo
+version: 1.0.0
+dependencies:
+  bar:
+    version: "<2.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+      '''
+name: foo
+version: 2.0.0
+dependencies:
+  bar:
+    version: "<3.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+      '''
+name: bar
+version: 1.0.0
+dependencies:
+  baz:
+    version: "<2.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''',
+      '''
+name: bar
+version: 2.0.0
+dependencies:
+  baz:
+    version: "<3.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''',
+      '''
+name: baz
+version: 1.0.0
+dependencies:
+  qux:
+    version: "<2.0.0"
+    repo: {name: qux, url: http://localhost:3123}
+''',
+      '''
+name: baz
+version: 2.0.0
+dependencies:
+  qux:
+    version: "<3.0.0"
+    repo: {name: qux, url: http://localhost:3123}
+''',
+    '''
+name: qux
+version: 1.0.0
+''',
+    '''
+name: qux
+version: 2.0.0
+''',
+    '''
+name: newdep
+version: 2.0.0
+dependencies:
+  baz:
+    version: ">=1.5.0"
+    repo: {name: baz, url: http://localhost:3123}
+''']);
 
-      package("bar", "1.0.0", [dependency("baz", "<2.0.0")]),
-      package("bar", "2.0.0", [dependency("baz", "<3.0.0")]),
-
-      package("baz", "1.0.0", [dependency("qux", "<2.0.0")]),
-      package("baz", "2.0.0", [dependency("qux", "<3.0.0")]),
-
-      package("qux", "1.0.0"),
-      package("qux", "2.0.0"),
-
-      package("newdep", "2.0.0", [dependency("baz", ">=1.5.0")])
-    ]);
-
-    appDir([dependency("foo"), dependency("newdep")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+  newdep:
+    repo: {name: newdep, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({
-      "foo": "2.0.0",
-      "bar": "2.0.0",
-      "baz": "2.0.0",
-      "qux": "1.0.0",
-      "newdep": "2.0.0"
-    }).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 2.0.0");')
+      ]),
+      dir('bar', [
+        file('bar.dart', 'main() => print("bar 2.0.0");')
+      ]),
+      dir('baz', [
+        file('baz.dart', 'main() => print("baz 2.0.0");')
+      ]),
+      dir('qux', [
+        file('qux.dart', 'main() => print("qux 1.0.0");')
+      ]),
+      dir('newdep', [
+        file('newdep.dart', 'main() => print("newdep 2.0.0");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
@@ -610,46 +1030,127 @@ installCommand() {
   test("doesn't unlock dependencies if a new dependency is already "
       "satisfied", () {
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0", [dependency("bar", "<2.0.0")]),
-      package("bar", "1.0.0", [dependency("baz", "<2.0.0")]),
-      package("baz", "1.0.0")
-    ]);
+      '''
+name: foo
+version: 1.0.0
+dependencies:
+  bar:
+    version: "<2.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+      '''
+name: bar
+version: 1.0.0
+dependencies:
+  baz:
+    version: "<2.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''',
+    '''
+name: baz
+version: 1.0.0
+''']);
 
-    appDir([dependency("foo")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({
-      "foo": "1.0.0",
-      "bar": "1.0.0",
-      "baz": "1.0.0"
-    }).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ]),
+      dir('bar', [
+        file('bar.dart', 'main() => print("bar 1.0.0");')
+      ]),
+      dir('baz', [
+        file('baz.dart', 'main() => print("baz 1.0.0");')
+      ])
+    ]).scheduleValidate();
 
     servePackages("localhost", 3123, [
-      package("foo", "1.0.0", [dependency("bar", "<2.0.0")]),
-      package("foo", "2.0.0", [dependency("bar", "<3.0.0")]),
+      '''
+name: foo
+version: 1.0.0
+dependencies:
+  bar:
+    version: "<2.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+      '''
+name: foo
+version: 2.0.0
+dependencies:
+  bar:
+    version: "<3.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+      '''
+name: bar
+version: 1.0.0
+dependencies:
+  baz:
+    version: "<2.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''',
+      '''
+name: bar
+version: 2.0.0
+dependencies:
+  baz:
+    version: "<3.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''',
+      '''
+name: baz
+version: 1.0.0
+''',
+      '''
+name: baz
+version: 2.0.0
+''',
+    '''
+name: newdep
+version: 2.0.0
+dependencies:
+  baz:
+    version: ">=1.0.0"
+    repo: {name: baz, url: http://localhost:3123}
+''']);
 
-      package("bar", "1.0.0", [dependency("baz", "<2.0.0")]),
-      package("bar", "2.0.0", [dependency("baz", "<3.0.0")]),
-
-      package("baz", "1.0.0"),
-      package("baz", "2.0.0"),
-
-      package("newdep", "2.0.0", [dependency("baz", ">=1.0.0")])
-    ]);
-
-    appDir([dependency("foo"), dependency("newdep")]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+  newdep:
+    repo: {name: newdep, url: http://localhost:3123}
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
 
-    packagesDir({
-      "foo": "1.0.0",
-      "bar": "1.0.0",
-      "baz": "1.0.0",
-      "newdep": "2.0.0"
-    }).scheduleValidate();
+    dir(packagesPath, [
+      dir('foo', [
+        file('foo.dart', 'main() => print("foo 1.0.0");')
+      ]),
+      dir('bar', [
+        file('bar.dart', 'main() => print("bar 1.0.0");')
+      ]),
+      dir('baz', [
+        file('baz.dart', 'main() => print("baz 1.0.0");')
+      ]),
+      dir('newdep', [
+        file('newdep.dart', 'main() => print("newdep 2.0.0");')
+      ])
+    ]).scheduleValidate();
 
     run();
   });
@@ -667,7 +1168,15 @@ updateCommand() {
       file('bar.dart', 'main() => "bar";')
     ]).scheduleCreate();
 
-    appDir([{"git": "../foo.git"}, {"git": "../bar.git"}]).scheduleCreate();
+    dir(appPath, [
+      file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+  bar:
+    git: ../bar.git
+''')
+    ]).scheduleCreate();
 
     schedulePub(args: ['install'],
         output: const RegExp(@"Dependencies installed!$"));
@@ -716,7 +1225,15 @@ updateCommand() {
         file('bar.dart', 'main() => "bar";')
       ]).scheduleCreate();
 
-      appDir([{"git": "../foo.git"}, {"git": "../bar.git"}]).scheduleCreate();
+      dir(appPath, [
+        file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+  bar:
+    git: ../bar.git
+''')
+      ]).scheduleCreate();
 
       schedulePub(args: ['install'],
           output: const RegExp(@"Dependencies installed!$"));
@@ -759,14 +1276,24 @@ updateCommand() {
 
       git('foo.git', [
         file('foo.dart', 'main() => "foo";'),
-        libPubspec("foo", "1.0.0", [{"git": "../foo-dep.git"}])
+        file('pubspec.yaml', '''
+dependencies:
+  foo-dep:
+    git: ../foo-dep.git
+''')
       ]).scheduleCreate();
 
       git('foo-dep.git', [
-        file('foo-dep.dart', 'main() => "foo-dep";'),
+        file('foo-dep.dart', 'main() => "foo-dep";')
       ]).scheduleCreate();
 
-      appDir([{"git": "../foo.git"}]).scheduleCreate();
+      dir(appPath, [
+        file('pubspec.yaml', '''
+dependencies:
+  foo:
+    git: ../foo.git
+''')
+      ]).scheduleCreate();
 
       schedulePub(args: ['install'],
           output: const RegExp(@"Dependencies installed!$"));
@@ -774,7 +1301,11 @@ updateCommand() {
       dir(packagesPath, [
         dir('foo', [
           file('foo.dart', 'main() => "foo";'),
-          libPubspec("foo", "1.0.0", [{"git": "../foo-dep.git"}])
+          file('pubspec.yaml', '''
+dependencies:
+  foo-dep:
+    git: ../foo-dep.git
+''')
         ]),
         dir('foo-dep', [
           file('foo-dep.dart', 'main() => "foo-dep";')
@@ -783,7 +1314,11 @@ updateCommand() {
 
       git('foo.git', [
         file('foo.dart', 'main() => "foo 2";'),
-        libPubspec("foo", "1.0.0", [{"git": "../foo-dep.git"}])
+        file('pubspec.yaml', '''
+dependencies:
+  foo-dep:
+    git: ../foo-dep.git
+''')
       ]).scheduleCreate();
 
       git('foo-dep.git', [
@@ -796,7 +1331,11 @@ updateCommand() {
       dir(packagesPath, [
         dir('foo', [
           file('foo.dart', 'main() => "foo 2";'),
-          libPubspec("foo", "1.0.0", [{"git": "../foo-dep.git"}])
+          file('pubspec.yaml', '''
+dependencies:
+  foo-dep:
+    git: ../foo-dep.git
+''')
         ]),
         dir('foo-dep', [
           file('foo-dep.dart', 'main() => "foo-dep";')
@@ -809,32 +1348,80 @@ updateCommand() {
     test("updates one locked pub server package's dependencies if it's "
         "necessary", () {
       servePackages("localhost", 3123, [
-        package("foo", "1.0.0", [dependency("foo-dep")]),
-        package("foo-dep", "1.0.0")
+        '''
+name: foo
+version: 1.0.0
+dependencies:
+  foo-dep:
+    repo:
+      name: foo-dep
+      url: http://localhost:3123
+''',
+        '{name: foo-dep, version: 1.0.0}'
       ]);
 
-      appDir([dependency("foo")]).scheduleCreate();
+      dir(appPath, [
+        file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo:
+      name: foo
+      url: http://localhost:3123
+''')
+      ]).scheduleCreate();
 
       schedulePub(args: ['install'],
           output: const RegExp(@"Dependencies installed!$"));
 
-      packagesDir({
-        "foo": "1.0.0",
-        "foo-dep": "1.0.0"
-      }).scheduleValidate();
+      dir(packagesPath, [
+        dir('foo', [
+          file('foo.dart', 'main() => print("foo 1.0.0");'),
+          file('pubspec.yaml', '''
+name: foo
+version: 1.0.0
+dependencies:
+  foo-dep:
+    repo:
+      name: foo-dep
+      url: http://localhost:3123
+''')
+        ]),
+        dir('foo-dep', [
+          file('foo-dep.dart', 'main() => print("foo-dep 1.0.0");')
+        ])
+      ]).scheduleValidate();
 
       servePackages("localhost", 3123, [
-        package("foo", "2.0.0", [dependency("foo-dep", ">1.0.0")]),
-        package("foo-dep", "2.0.0")
+        '''
+name: foo
+version: 2.0.0
+dependencies:
+  foo-dep:
+    repo: {name: foo-dep, url: http://localhost:3123}
+    version: ">1.0.0"
+''',
+        '{name: foo-dep, version: 2.0.0}'
       ]);
 
       schedulePub(args: ['update', 'foo'],
           output: const RegExp(@"Dependencies updated!$"));
 
-      packagesDir({
-        "foo": "2.0.0",
-        "foo-dep": "2.0.0"
-      }).scheduleValidate();
+      dir(packagesPath, [
+        dir('foo', [
+          file('foo.dart', 'main() => print("foo 2.0.0");'),
+          file('pubspec.yaml', '''
+name: foo
+version: 2.0.0
+dependencies:
+  foo-dep:
+    repo: {name: foo-dep, url: http://localhost:3123}
+    version: ">1.0.0"
+''')
+        ]),
+        dir('foo-dep', [
+          file('foo-dep.dart', 'main() => print("foo-dep 2.0.0");')
+        ])
+      ]).scheduleValidate();
 
       run();
     });
@@ -842,35 +1429,71 @@ updateCommand() {
     test("updates a locked package's dependers in order to get it to max "
         "version", () {
       servePackages("localhost", 3123, [
-        package("foo", "1.0.0", [dependency("bar", "<2.0.0")]),
-        package("bar", "1.0.0")
+        '''
+name: foo
+version: 1.0.0
+dependencies:
+  bar:
+    version: "<2.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+        '{name: bar, version: 1.0.0}'
       ]);
 
-      appDir([dependency("foo"), dependency("bar")]).scheduleCreate();
+      dir(appPath, [
+        file('pubspec.yaml', '''
+dependencies:
+  foo:
+    repo: {name: foo, url: http://localhost:3123}
+  bar:
+    repo: {name: bar, url: http://localhost:3123}
+''')
+      ]).scheduleCreate();
 
       schedulePub(args: ['install'],
           output: const RegExp(@"Dependencies installed!$"));
 
-      packagesDir({
-        "foo": "1.0.0",
-        "bar": "1.0.0"
-      }).scheduleValidate();
+      dir(packagesPath, [
+        dir('foo', [
+          file('foo.dart', 'main() => print("foo 1.0.0");'),
+        ]),
+        dir('bar', [
+          file('bar.dart', 'main() => print("bar 1.0.0");')
+        ])
+      ]).scheduleValidate();
 
       servePackages("localhost", 3123, [
-        package("foo", "1.0.0", [dependency("bar", "<2.0.0")]),
-        package("foo", "2.0.0", [dependency("bar", "<3.0.0")]),
-
-        package("bar", "1.0.0"),
-        package("bar", "2.0.0")
+        '''
+name: foo
+version: 1.0.0
+dependencies:
+  bar:
+    version: "<2.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+        '''
+name: foo
+version: 2.0.0
+dependencies:
+  bar:
+    version: "<3.0.0"
+    repo: {name: bar, url: http://localhost:3123}
+''',
+        '{name: bar, version: 1.0.0}',
+        '{name: bar, version: 2.0.0}'
       ]);
 
       schedulePub(args: ['update', 'bar'],
           output: const RegExp(@"Dependencies updated!$"));
 
-      packagesDir({
-        "foo": "2.0.0",
-        "bar": "2.0.0"
-      }).scheduleValidate();
+      dir(packagesPath, [
+        dir('foo', [
+          file('foo.dart', 'main() => print("foo 2.0.0");'),
+        ]),
+        dir('bar', [
+          file('bar.dart', 'main() => print("bar 2.0.0");')
+        ])
+      ]).scheduleValidate();
 
       run();
     });
diff --git a/utils/tests/pub/test_pub.dart b/utils/tests/pub/test_pub.dart
index 067343330b8..d272cb7f026 100644
--- a/utils/tests/pub/test_pub.dart
+++ b/utils/tests/pub/test_pub.dart
@@ -18,10 +18,7 @@
 
 #import('../../../pkg/unittest/unittest.dart');
 #import('../../lib/file_system.dart', prefix: 'fs');
-#import('../../pub/git_source.dart');
 #import('../../pub/io.dart');
-#import('../../pub/repo_source.dart');
-#import('../../pub/sdk_source.dart');
 #import('../../pub/utils.dart');
 #import('../../pub/yaml/yaml.dart');
 
@@ -126,16 +123,17 @@ Future _closeServer() {
 
 /**
  * Creates an HTTP server that replicates the structure of pub.dartlang.org.
- * [pubspecs] is a list of unserialized pubspecs representing the packages to
+ * [pubspecs] is a list of YAML-format pubspecs representing the packages to
  * serve.
  */
-void servePackages(String host, int port, List<Map> pubspecs) {
+void servePackages(String host, int port, List<String> pubspecs) {
   var packages = <String, Map<String, String>>{};
-  for (var spec in pubspecs) {
-    var name = spec['name'];
-    var version = spec['version'];
-    packages.putIfAbsent(name, () => <String, String>{})[version] = yaml(spec);
-  }
+  pubspecs.forEach((spec) {
+    var parsed = loadYaml(spec);
+    var name = parsed['name'];
+    var version = parsed['version'];
+    packages.putIfAbsent(name, () => <String, String>{})[version] = spec;
+  });
 
   serve(host, port, [
     dir('packages', flatten(packages.getKeys().map((name) {
@@ -158,158 +156,6 @@ void servePackages(String host, int port, List<Map> pubspecs) {
   ]);
 }
 
-/** Converts [value] into a YAML string. */
-String yaml(value) => JSON.stringify(value);
-
-/**
- * Describes a file named `pubspec.yaml` with the given YAML-serialized
- * [contents], which should be a serializable object.
- *
- * [contents] may contain [Future]s that resolve to serializable objects, which
- * may in turn contain [Future]s recursively.
- */
-Descriptor pubspec(Map contents) {
-  return async(_awaitObject(contents).transform((resolvedContents) =>
-      file("pubspec.yaml", yaml(resolvedContents))));
-}
-
-/**
- * Describes a file named `pubspec.yaml` for an application package with the
- * given [dependencies].
- */
-Descriptor appPubspec(List dependencies) =>
-  pubspec({"dependencies": _dependencyListToMap(dependencies)});
-
-/**
- * Describes a file named `pubspec.yaml` for a library package with the given
- * [name], [version], and [dependencies].
- */
-Descriptor libPubspec(String name, String version, [List dependencies]) =>
-  pubspec(package(name, version, dependencies));
-
-/**
- * Describes a map representing a library package with the given [name],
- * [version], and [dependencies].
- */
-Map package(String name, String version, [List dependencies]) {
-  var package = {"name": name, "version": version};
-  if (dependencies != null) {
-    package["dependencies"] = _dependencyListToMap(dependencies);
-  }
-  return package;
-}
-
-/**
- * Describes a map representing a dependency on a package in the package
- * repository.
- */
-Map dependency(String name, [String versionConstraint]) {
-  var dependency = {"repo": {"name": name, "url": "http://localhost:3123"}};
-  if (versionConstraint != null) dependency["version"] = versionConstraint;
-  return dependency;
-}
-
-/**
- * Describes a directory for a package installed from the mock package repo.
- * This directory is of the form found in the `packages/` directory.
- */
-DirectoryDescriptor packageDir(String name, String version) {
-  return dir(name, [
-    file("$name.dart", 'main() => print("$name $version");')
-  ]);
-}
-
-/**
- * Describes a directory for a package installed from the mock package server.
- * This directory is of the form found in the global package cache.
- */
-DirectoryDescriptor packageCacheDir(String name, String version) {
-  return dir("$name-$version", [
-    file("$name.dart", 'main() => print("$name $version");')
-  ]);
-}
-
-/**
- * Describes a directory for a Git package. This directory is of the form found
- * in the global package cache.
- */
-DirectoryDescriptor gitPackageCacheDir(String name, [int modifier]) {
-  var value = name;
-  if (modifier != null) value = "$name $modifier";
-  return dir(new RegExp("$name${@'-[a-f0-9]+'}"), [
-    file('$name.dart', 'main() => "$value";')
-  ]);
-}
-
-/**
- * Describes the `packages/` directory containing all the given [packages],
- * which should be name/version pairs. The packages will be validated against
- * the format produced by the mock package server.
- */
-DirectoryDescriptor packagesDir(Map<String, String> packages) {
-  var contents = <Map>[];
-  packages.forEach((name, version) {
-    contents.add(packageDir(name, version));
-  });
-  return dir(packagesPath, contents);
-}
-
-/**
- * Describes the global package cache directory containing all the given
- * [packages], which should be name/version pairs. The packages will be
- * validated against the format produced by the mock package server.
- *
- * A package's value may also be a list of versions, in which case all versions
- * are expected to be installed.
- */
-DirectoryDescriptor cacheDir(Map packages) {
-  var contents = <Map>[];
-  packages.forEach((name, versions) {
-    if (versions is! List) versions = [versions];
-    for (var version in versions) {
-      contents.add(packageCacheDir(name, version));
-    }
-  });
-  return dir(cachePath, [
-    dir('repo', [dir('localhost%583123', contents)])
-  ]);
-}
-
-/**
- * Describes the application directory, containing only a pubspec specifying the
- * given [dependencies].
- */
-DirectoryDescriptor appDir(List dependencies) =>
-  dir(appPath, [appPubspec(dependencies)]);
-
-/**
- * Converts a list of dependencies as passed to [package] into a hash as used in
- * a pubspec.
- */
-Map _dependencyListToMap(List<Map> dependencies) {
-  var result = <String, Map>{};
-  dependencies.map((dependency) {
-    var sourceName = only(dependency.getKeys());
-    var source;
-    switch (sourceName) {
-    case "git":
-      source = new GitSource();
-      break;
-    case "repo":
-      source = new RepoSource();
-      break;
-    case "sdk":
-      source = new SdkSource('');
-      break;
-    default:
-      throw 'Unknown source "$sourceName"';
-    }
-
-    result[source.packageName(dependency[sourceName])] = dependency;
-  });
-  return result;
-}
-
 /**
  * The path of the package cache directory used for tests. Relative to the
  * sandbox directory.
@@ -739,15 +585,23 @@ class DirectoryDescriptor extends Descriptor {
    * the creation is done.
    */
   Future<Directory> create(parentDir) {
-    // Create the directory.
-    return ensureDir(join(parentDir, _stringName)).chain((dir) {
-      if (contents == null) return new Future<Directory>.immediate(dir);
+    final completer = new Completer<Directory>();
 
-      // Recursively create all of its children.
-      final childFutures = contents.map((child) => child.create(dir));
-      // Only complete once all of the children have been created too.
-      return Futures.wait(childFutures).transform((_) => dir);
+    // Create the directory.
+    ensureDir(join(parentDir, _stringName)).then((dir) {
+      if (contents == null) {
+        completer.complete(dir);
+      } else {
+        // Recursively create all of its children.
+        final childFutures = contents.map((child) => child.create(dir));
+        Futures.wait(childFutures).then((_) {
+          // Only complete once all of the children have been created too.
+          completer.complete(dir);
+        });
+      }
     });
+
+    return completer.future;
   }
 
   /**
@@ -949,31 +803,6 @@ class TarFileDescriptor extends Descriptor {
   }
 }
 
-/**
- * Takes a simple data structure (composed of [Map]s, [List]s, scalar objects,
- * and [Future]s) and recursively resolves all the [Future]s contained within.
- * Completes with the fully resolved structure.
- */
-Future _awaitObject(object) {
-  // Unroll nested futures.
-  if (object is Future) return object.chain(_awaitObject);
-  if (object is Collection) return Futures.wait(object.map(_awaitObject));
-  if (object is! Map) return new Future.immediate(object);
-
-  var pairs = <Future<Pair>>[];
-  object.forEach((key, value) {
-    pairs.add(_awaitObject(value)
-        .transform((resolved) => new Pair(key, resolved)));
-  });
-  return Futures.wait(pairs).transform((resolvedPairs) {
-    var map = {};
-    for (var pair in resolvedPairs) {
-      map[pair.first] = pair.last;
-    }
-    return map;
-  });
-}
-
 /**
  * Schedules a callback to be called as part of the test case.
  */