Re-apply "Enable use of #import stmts containing relative paths in Dart multitests"

tools/testing/dart/test_suite.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Classes and methods for enumerating and preparing tests.
  *
  * This library includes:
  *
  * - Creating tests by listing all the Dart files in certain directories,
@@ skipping 653 matching lines @@
       buildPath.removeRange(0, 1);
       if (buildPath.last() == '') buildPath.removeLast();
       buildPath.addAll(generatedTestPath);
       generatedTestPath = buildPath;
       tempDir = new Directory(tempDirPath);
       if (!tempDir.existsSync()) {
         tempDir.createSync();
       }
     }
     tempDirPath = new File(tempDirPath).fullPathSync().replaceAll('\\', '/');
-
-    for (String subdirectory in generatedTestPath) {
-      tempDirPath = '$tempDirPath/$subdirectory';
-      tempDir = new Directory(tempDirPath);
-      if (!tempDir.existsSync()) {
-        tempDir.createSync();
-      }
-    }
-    return tempDir;
+    return TestUtils.mkdirRecursive(tempDirPath, 
+      Strings.join(generatedTestPath, '/'));
   }
 
   String get scriptType() {
     switch (configuration['component']) {
       case 'dartium':
         return 'application/dart';
       case 'chromium':
       case 'frogium':
       case 'legium':
       case 'webdriver':
@@ skipping 323 matching lines @@
          '$dartDir/third_party/hamcrest/v1_3/hamcrest-generator-1.3.0RC2.jar',
          '$dartDir/third_party/hamcrest/v1_3/hamcrest-integration-1.3.0RC2.jar',
          '$dartDir/third_party/hamcrest/v1_3/hamcrest-library-1.3.0RC2.jar',
          '$dartDir/third_party/junit/v4_8_2/junit.jar'],
         ':');  // Path separator.
   }
 }
 
 
 class TestUtils {
+  
+  /** 
+   * Creates a directory using a [relativePath] to an existing 
+   * [base] directory if that [relativePath] does not already exist.
+   */
+  static Directory mkdirRecursive(String base, String relativePath) {
+    Directory baseDir = new Directory(base);
+    Expect.isTrue(baseDir.existsSync(),
+      "Expected ${base} to already exist");  
+    var tempDir = new Directory(base);
+    for (String dir in relativePath.split('/')) {
+      base = "$base/$dir";
+      tempDir = new Directory(base);
+      if (!tempDir.existsSync()) {
+          tempDir.createSync();
+      }
+      Expect.isTrue(tempDir.existsSync(), "Failed to create ${tempDir.path}");
+    }
+    return tempDir;
+  }
+
+  /**
+   * Copy a [source] file to a new place.
+   * Assumes that the directory for [dest] already exists.
+   */
+  static void copyFile(File source, File dest) {
+    List contents = source.readAsBytesSync();
+    RandomAccessFile handle = dest.openSync(FileMode.WRITE);
+    handle.writeListSync(contents, 0, contents.length);
+    handle.closeSync();
+  }
+  
   static String executableSuffix(String component) {
     if (new Platform().operatingSystem() == 'windows') {
       if (component != 'frogium'
           && component != 'legium'
           && component != 'webdriver') {
         return '.exe';
       } else {
         return '.bat';
       }
     }
@@ skipping 137 matching lines @@
  * $noCrash tests are expected to be flaky but not crash
  * $pass tests are expected to pass
  * $failOk tests are expected to fail that we won't fix
  * $fail tests are expected to fail that we should fix
  * $crash tests are expected to crash that we should fix
  * $timeout tests are allowed to timeout
 """;
     print(report);
    }
 }