Use environment variables to find the Dart SDK and the Pub cache directory.

utils/tests/pub/test_pub.dart

Index: utils/tests/pub/test_pub.dart
diff --git a/utils/tests/pub/test_pub.dart b/utils/tests/pub/test_pub.dart
index 6e7f209814306f4b9dbb2f8c4757c524201e992c..f7ae3a95ee9ae6f6671aee264fac34764006d93c 100644
--- a/utils/tests/pub/test_pub.dart
+++ b/utils/tests/pub/test_pub.dart
@@ -202,19 +202,26 @@ void schedulePub([List<String> args, Pattern output, Pattern error,
     String pathInSandbox(path) => join(getFullPath(sandboxDir), path);
 
     return ensureDir(pathInSandbox(appPath)).chain((_) {
-      // TODO(rnystrom): Hack in the cache directory path. Should pass this in
-      // using environment var once #752 is done.
-      args.insertRange(0, 1, '--cachedir=${pathInSandbox(cachePath)}');
-
-      // TODO(rnystrom): Hack in the SDK path. Should pass this in using
-      // environment var once #752 is done.
-      args.insertRange(0, 1, '--sdkdir=${pathInSandbox(sdkPath)}');
-
-      // If an error occurs in pub during testing, we want it to print the stack
-      // trace so it can be debugged.
-      args.insertRange(0, 1, '--trace');
-
-      return _runPub(args, pathInSandbox(appPath), pipeStdout: output == null,
+      // Find a dart executable we can use to run pub. Uses the one that the
+      // test infrastructure uses. We are not using new Options.executable here
+      // because that gets confused if you invoked Dart through a shell script.
+      var scriptDir = new File(new Options().script).directorySync().path;
+      var platform = Platform.operatingSystem;
+      var dartBin = join(scriptDir, '../../../tools/testing/bin/$platform/dart');
+
+      // Find the main pub entrypoint.
+      var pubPath = fs.joinPaths(scriptDir, '../../pub/pub.dart');
+
+      var dartArgs =
+        ['--enable-type-checks', '--enable-asserts', pubPath, '--trace'];
+      dartArgs.addAll(args);
+
+      var environment = new Map.from(Platform.environment);
+      environment['PUB_CACHE'] = pathInSandbox(cachePath);
+      environment['DART_SDK'] = pathInSandbox(sdkPath);
+
+      return runProcess(dartBin, dartArgs, workingDir: pathInSandbox(appPath),
+          environment: environment, pipeStdout: output == null,
           pipeStderr: error == null);
     }).transform((result) {
       _validateOutput(output, result.stdout);
@@ -278,24 +285,6 @@ Future _runScheduled(Directory parentDir, List<_ScheduledEvent> scheduled) {
   return runNextEvent();
 }
 
-Future<ProcessResult> _runPub(List<String> pubArgs, String workingDir,
-    [bool pipeStdout=false, bool pipeStderr=false]) {
-  // Find a dart executable we can use to run pub. Uses the one that the
-  // test infrastructure uses. We are not using new Options.executable here
-  // because that gets confused if you invoked Dart through a shell script.
-  final scriptDir = new File(new Options().script).directorySync().path;
-  final platform = Platform.operatingSystem;
-  final dartBin = join(scriptDir, '../../../tools/testing/bin/$platform/dart');
-
-  // Find the main pub entrypoint.
-  final pubPath = fs.joinPaths(scriptDir, '../../pub/pub.dart');
-
-  final args = ['--enable-type-checks', '--enable-asserts', pubPath];
-  args.addAll(pubArgs);
-
-  return runProcess(dartBin, args, workingDir, pipeStdout, pipeStderr);
-}
-
 /**
  * Compares the [actual] output from running pub with [expected]. For [String]
  * patterns, ignores leading and trailing whitespace differences and tries to