Let docgen detect a dart-sdk directory that's differently named, and do it correctly on bleeding ed…

pkg/docgen/lib/src/generator.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.
 
 library docgen.generator;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
@@ skipping 43 matching lines @@
 /// also be documented.
 /// If [parseSdk] is `true`, then all Dart SDK libraries will be documented.
 /// This option is useful when only the SDK libraries are needed.
 ///
 /// Returned Future completes with true if document generation is successful.
 Future<bool> generateDocumentation(List<String> files, {String packageRoot,
     bool outputToYaml: true, bool includePrivate: false, bool includeSdk: false,
     bool parseSdk: false, String introFileName: '',
     out: DEFAULT_OUTPUT_DIRECTORY, List<String> excludeLibraries: const [], bool
     includeDependentPackages: false, String startPage, String dartBinaryValue,
-    String pubScriptValue, bool indentJSON: false}) {
+    String pubScriptValue, bool indentJSON: false, String sdk}) {
   _excluded = excludeLibraries;
   dartBinary = dartBinaryValue;
   pubScript = pubScriptValue;
 
   logger.onRecord.listen((record) => print(record.message));
 
   _ensureOutputDirectory(out);
   var updatedPackageRoot = _obtainPackageRoot(packageRoot, parseSdk, files);
 
   var requestedLibraries = _findLibrariesToDocument(files,
       includeDependentPackages);
 
   var allLibraries = []..addAll(requestedLibraries);
   if (includeSdk) {
     allLibraries.addAll(_listSdk());
   }
 
   return getMirrorSystem(allLibraries, includePrivate,
-      packageRoot: updatedPackageRoot, parseSdk: parseSdk)
+      packageRoot: updatedPackageRoot, parseSdk: parseSdk, sdkRoot: sdk)
       .then((MirrorSystem mirrorSystem) {
     if (mirrorSystem.libraries.isEmpty) {
       throw new StateError('No library mirrors were created.');
     }
     initializeTopLevelLibraries(mirrorSystem);
 
     var availableLibraries = mirrorSystem.libraries.values
         .where((each) => each.uri.scheme == 'file');
     var availableLibrariesByPath =
         new Map.fromIterables(availableLibraries.map((each) => each.uri),
             availableLibraries);
     var librariesToDocument = requestedLibraries
           .map((each) {
             return availableLibrariesByPath
                 .putIfAbsent(each, () => throw "Missing library $each");
     }).toList();
     librariesToDocument.addAll((includeSdk || parseSdk) ? sdkLibraries : []);
     librariesToDocument.removeWhere((x) => _excluded.contains(
         dart2js_util.nameOf(x)));
     _documentLibraries(librariesToDocument, includeSdk, parseSdk, introFileName,
         startPage, indentJSON);
     return true;
   });
 }
 
 
 /// Analyzes set of libraries by getting a mirror system and triggers the
 /// documentation of the libraries.
 Future<MirrorSystem> getMirrorSystem(List<Uri> libraries,
-    bool includePrivate, {String packageRoot, bool parseSdk: false}) {
+    bool includePrivate, {String packageRoot, bool parseSdk: false,
+    String sdkRoot}) {
   if (libraries.isEmpty) throw new StateError('No Libraries.');
 
   includePrivateMembers = includePrivate;
 
   // Finds the root of SDK library based off the location of docgen.
   // We have two different places to look, depending if we're in a development
   // repo or in a built SDK, either sdk or dart-sdk respectively
-  var root = rootDirectory;
-  var sdkRoot = path.normalize(path.absolute(path.join(root, 'sdk')));
-  if (!new Directory(sdkRoot).existsSync()) {
-    sdkRoot = path.normalize(path.absolute(path.join(root, 'dart-sdk')));
+  if (sdkRoot == null) {
+    var root = rootDirectory;
+    sdkRoot = path.normalize(path.absolute(path.join(root, 'sdk')));
+    if (!new Directory(sdkRoot).existsSync()) {
+      sdkRoot = path.normalize(path.absolute(path.join(root, 'dart-sdk')));
+    }
   }
   logger.info('SDK Root: ${sdkRoot}');
   return analyzeLibraries(libraries, sdkRoot, packageRoot: packageRoot);
 }
 
 /// Writes [text] to a file in the output directory.
 void _writeToFile(String text, String filename) {
   if (text == null) return;
 
   var filePath = path.join(_outputDirectory, filename);
@@ skipping 339 matching lines @@
   * [Samples](http://www.dartlang.org/samples/)
   * [A Tour of the Dart Libraries](http://www.dartlang.org/docs/dart-up-and-running/contents/ch03.html)
 
 This API reference is automatically generated from the source code in the
 [Dart project](https://code.google.com/p/dart/).
 If you'd like to contribute to this documentation, see
 [Contributing](https://code.google.com/p/dart/wiki/Contributing)
 and
 [Writing API Documentation](https://code.google.com/p/dart/wiki/WritingApiDocumentation).
 """;