Use checked-in .package file for building and testing

tests/standalone/io/addlatexhash_test.dart

 #!/usr/bin/env 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.
 
 // testing ../../../tools/addlatexhash.dart
 
 import 'dart:io';
 import 'package:path/path.dart' as path;
 import '../../../tools/addlatexhash.dart';
 
 final scriptDir = path.dirname(path.fromUri(Platform.script));
 final dartRootDir = path.dirname(path.dirname(path.dirname(scriptDir)));
 final dartRootPath = dartRootDir.toString();
 
+List<String> packageOptions() {
+  if (Platform.packageRoot != null) {
+    return <String>['--package-root=${Platform.packageRoot}'];
+  } else if (Platform.packageConfig != null) {
+    return <String>['--packages=${Platform.packageConfig}'];
+  } else {
+    return <String>[];
+  }
+}
+
 // Check that the given ProcessResult indicates success; if so
 // return the standard output, otherwise report the failure
 checkAction(result, errorMessage) {
   if (result.exitCode != 0) {
     print(result.stdout);
     print(result.stderr);
     throw errorMessage;
   }
   return result.stdout;
 }
@@ skipping 48 matching lines @@
   final listName = par8timesName + "-list";
   final listFileName = "$listName.txt";
   final listPath = path.join(tmpDirPath, listFileName);
 
   // dart executable
   final dartExecutable = Platform.executable;
   if (dartExecutable == "") throw "dart executable not available";
 
   // actions to take
   runAddHash() {
-    var args = [
-      '--package-root=${Platform.packageRoot}',
+    var args = packageOptions();
+    args.addAll([
       path.join(dartRootPath, "tools", "addlatexhash.dart"),
       tmpPar8timesPath,
       hashPath,
       listPath
-    ];
+    ]);
     return Process.runSync(dartExecutable, args);
   }
 
   // perform test
   new File(par8timesPath).copySync(tmpPar8timesPath);
   checkAction(runAddHash(), "addlatexhash.dart failed");
   var listFile = new File(listPath);
   var listLines = listFile.readAsLinesSync();
   var latestLine = null;
   var sameCount = 0;
@@ skipping 46 matching lines @@
 
   // dart executable
   final dartExecutable = Platform.executable;
   if (dartExecutable == "") throw "dart executable not available";
 
   // actions to take; rely on having latex and dvi2tty in PATH
   runLatex(fileName,workingDirectory) =>
       Process.runSync("latex", [fileName], workingDirectory: workingDirectory);
 
   runAddHash() {
-    var args = [
-      '--package-root=${Platform.packageRoot}',
+    var args = packageOptions();
+    args.addAll([
       path.join(dartRootPath, "tools", "addlatexhash.dart"),
       tmpSpecPath,
       hashPath,
       listPath
-    ];
+    ]);
     return Process.runSync(dartExecutable, args);
   }
 
   runDvi2tty(dviFile) =>
       Process.runSync("dvi2tty", [dviFile], workingDirectory: tmpDirPath);
 
   chkDvi2tty(file, subject) =>
       checkAction(runDvi2tty(file), "dvitty on $subject failed");
 
   // perform test
@@ skipping 29 matching lines @@
 main([args]) {
   testCutMatch();
   testSisp();
 
   runWithTempDir(testSameHash);
   // latex and dvi2tty are not installed in the standard test environment
   if (args.length > 0 && args[0] == "local") {
     runWithTempDir(testSameDVI);
   }
 }