Make pub use the SDK's "version" file for its version.

utils/tests/pub/real_version_test.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.
+
+library pub_tests;
+
+import 'dart:io';
+
+import 'test_pub.dart';
+import '../../../pkg/path/lib/path.dart' as path;
+import '../../../pkg/unittest/lib/unittest.dart';
+
+main() {
+  initConfig();
+
+  // This test is a bit funny.
+  //
+  // Pub parses the "version" file that gets generated and shipped with the SDK.
+  // Most of the pub tests here generate a synthetic SDK directory so that we
+  // can tests against a known SDK state. But we want to make sure that the
+  // actual version file that gets created is also one pub can parse. If this
+  // test fails, it means the version file's format has changed in a way pub
+  // didn't expect.
+  //
+  // Note that this test expects to be invoked from a Dart executable that is
+  // in the built SDK's "bin" directory. Note also that this invokes pub from
+  // the built SDK directory, and not the live pub code directly in the repo.
+  test('Pub can parse the real SDK "version" file', () {
+    // Get the path to the pub binary in the SDK.
+    var dartPath = new Options().executable;
+    var pubPath = path.join(path.dirname(dartPath), "pub");
+    if (Platform.operatingSystem == "windows") pubPath = '$pubPath.bat';
+
+    Process.run(pubPath, ['version']).then(expectAsync1((result) {
+      expect(result.stdout, startsWith("Pub"));
+      expect(result.exitCode, equals(0));
+    }));
+  });
+}