Support transformers that depend on other transformers.

sdk/lib/_internal/pub/test/test_pub.dart

 // Copyright (c) 2013, 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.
 
 /// Test infrastructure for testing pub. Unlike typical unit tests, most pub
 /// tests are integration tests that stage some stuff on the file system, run
 /// pub, and then validate the results. This library provides an API to build
 /// tests like that.
 library test_pub;
 
@@ skipping 589 matching lines @@
     return gitlib.isInstalled.then((installed) {
       if (installed) return;
       if (runningOnBuildbot) return;
       currentSchedule.abort();
     });
   }, 'ensuring that Git is installed');
 }
 
 /// Create a lock file for [package] without running `pub install`.
 ///
-/// This creates a lock file with only path dependencies. [dependencies] is a
-/// map of dependency names to paths. [pkg] is a list of packages in the Dart
-/// repo's "pkg" directory; each package listed here and all its dependencies
-/// will be linked to the version in the Dart repo.
-void createLockFile(String package, Map<String, String> dependencies,
-    {Iterable<String> pkg}) {
+/// This creates a lock file with only path dependencies. [sandbox] is a list of
+/// dependencies to be found in the sandbox directory. [pkg] is a list of
+/// packages in the Dart repo's "pkg" directory; each package listed here and
+/// all its dependencies will be linked to the version in the Dart repo.
+void createLockFile(String package, {Iterable<String> sandbox,
+    Iterable<String> pkg}) {
+  var dependencies = {};
+
+  if (sandbox != null) {
+    for (var package in sandbox) {
+      dependencies[package] = '../$package';
+    }
+  }
+
   if (pkg != null) {
     var pkgDir = path.absolute(path.join(
         path.dirname(Platform.executable),
         '..', '..', '..', '..', 'pkg'));
 
     _addPackage(String package) {
       if (dependencies.containsKey(package)) return;
       var packagePath = path.join(pkgDir, package);
       dependencies[package] = packagePath;
       var pubspec = loadYaml(
@@ skipping 202 matching lines @@
   bool matches(item, Map matchState) {
     if (item is! Pair) return false;
     return _firstMatcher.matches(item.first, matchState) &&
         _lastMatcher.matches(item.last, matchState);
   }
 
   Description describe(Description description) {
     description.addAll("(", ", ", ")", [_firstMatcher, _lastMatcher]);
   }
 }