Regenerate pub sources.

sdk/lib/_internal/pub_generated/lib/src/sdk.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.
+
+/// Operations relative to the user's installed Dart SDK.
 library pub.sdk;
+
 import 'dart:io';
+
 import 'package:path/path.dart' as path;
 import 'package:pub_semver/pub_semver.dart';
+
 import 'io.dart';
+
+/// Gets the path to the root directory of the SDK.
+///
+/// When running from the actual built SDK, this will be the SDK that contains
+/// the running Dart executable. When running from the repo, it will be the
+/// "sdk" directory in the Dart repository itself.
 final String rootDirectory =
     runningFromSdk ? _rootDirectory : path.join(repoRoot, "sdk");
+
+/// Gets the path to the root directory of the SDK, assuming that the currently
+/// running Dart executable is within it.
 final String _rootDirectory = path.dirname(path.dirname(Platform.executable));
+
+/// The SDK's revision number formatted to be a semantic version.
+///
+/// This can be set so that the version solver tests can artificially select
+/// different SDK versions.
 Version version = _getVersion();
+
+/// Determine the SDK's version number.
 Version _getVersion() {
+  // Some of the pub integration tests require an SDK version number, but the
+  // tests on the bots are not run from a built SDK so this lets us avoid
+  // parsing the missing version file.
   var sdkVersion = Platform.environment["_PUB_TEST_SDK_VERSION"];
   if (sdkVersion != null) return new Version.parse(sdkVersion);
+
   if (runningFromSdk) {
+    // Read the "version" file.
     var version = readTextFile(path.join(_rootDirectory, "version")).trim();
     return new Version.parse(version);
   }
+
+  // When running from the repo, read the canonical VERSION file in tools/.
+  // This makes it possible to run pub without having built the SDK first.
   var contents = readTextFile(path.join(repoRoot, "tools/VERSION"));
+
   parseField(name) {
     var pattern = new RegExp("^$name ([a-z0-9]+)", multiLine: true);
     var match = pattern.firstMatch(contents);
     return match[1];
   }
+
   var channel = parseField("CHANNEL");
   var major = parseField("MAJOR");
   var minor = parseField("MINOR");
   var patch = parseField("PATCH");
   var prerelease = parseField("PRERELEASE");
   var prereleasePatch = parseField("PRERELEASE_PATCH");
+
   var version = "$major.$minor.$patch";
   if (channel == "be") {
+    // TODO(rnystrom): tools/utils.py includes the svn commit here. Should we?
     version += "-edge";
   } else if (channel == "dev") {
     version += "-dev.$prerelease.$prereleasePatch";
   }
+
   return new Version.parse(version);
 }