Add a hidden pub command to generate core library stubs.

pkg/stub_core_library/bin/stub_core_library.dart

Index: pkg/stub_core_library/bin/stub_core_library.dart
diff --git a/pkg/stub_core_library/bin/stub_core_library.dart b/pkg/stub_core_library/bin/stub_core_library.dart
new file mode 100644
index 0000000000000000000000000000000000000000..9bf638c677fc6f00f37113436865a9542064a845
--- /dev/null
+++ b/pkg/stub_core_library/bin/stub_core_library.dart
@@ -0,0 +1,101 @@
+// 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 stub_core_library.bin;
+
+import 'dart:io';
+
+import 'package:args/args.dart';
+import 'package:path/path.dart' as p;
+
+import 'package:stub_core_library/src/utils.dart';
+import 'package:stub_core_library/stub_core_library.dart';
+
+/// A map from Dart core library sources to the filenames into which they should
+/// be generated.
+///
+/// The source paths are URL-formatted and relative to the Dart SDK root.
+const CORE_LIBRARIES = const {
+  'lib/io/io.dart': 'dart_io.dart',
+  'lib/html/html_common/html_common.dart': 'dart_html_common.dart',
+  'lib/html/html_common/metadata.dart': 'metadata.dart',
+  'lib/html/dartium/html_dartium.dart': 'dart_html.dart',
+  'lib/indexed_db/dartium/indexed_db_dartium.dart': 'dart_indexed_db.dart',
+  'lib/js/dartium/js_dartium.dart': 'dart_js.dart',
+  'lib/svg/dartium/svg_dartium.dart': 'dart_svg.dart',
+  'lib/web_audio/dartium/web_audio_dartium.dart': 'dart_web_audio.dart',
+  'lib/web_gl/dartium/web_gl_dartium.dart': 'dart_web_gl.dart',
+  'lib/web_sql/dartium/web_sql_dartium.dart': 'dart_web_sql.dart'
+};
+
+/// A map from stubbable "dart:" URLs to the names of the stub files they should
+/// be replaced with.
+const IMPORT_REPLACEMENTS = const {
+  'dart:io': 'dart_io.dart',
+  'dart:html_common': 'dart_html_common.dart',
+  'dart:html': 'dart_html.dart',
+  'dart:indexed_db': 'dart_indexed_db.dart',
+  'dart:js': 'dart_js.dart',
+  'dart:svg': 'dart_svg.dart',
+  'dart:web_audio': 'dart_web_audio.dart',
+  'dart:web_gl': 'dart_web_gl.dart',
+  'dart:web_sql': 'dart_web_sql.dart'
+};
+
+/// The exit code for a usage error.
+const USAGE_ERROR = 64;
+
+/// The root directory of the SDK.
+String get sdkRoot => p.join(
+    p.dirname(p.fromUri(Platform.script)), '..', '..', '..', 'sdk');
+
+/// The argument parser.
+final argParser = new ArgParser()
+    ..addFlag('help', abbr: 'h', help: 'Print this usage information.');
+
+/// The usage string.
+String get usage => """
+Generate Dart core library stubs.
+
+Usage: stub_core_libraries.dart <directory>
+
+${argParser.getUsage()}""";
+
+void main(List<String> arguments) {
+  var options;
+  try {
+    options = argParser.parse(arguments);
+  } on FormatException catch (e) {
+    stderr.writeln(e.message);
+    stderr.writeln(usage);
+    exitCode = USAGE_ERROR;
+    return;
+  }
+
+  if (options['help']) {
+    print(usage);
+    return;
+  }
+
+  var destination = options.rest.isEmpty ? p.current : options.rest.first;
+
+  // Don't allow extra arguments.
+  if (options.rest.length > 1) {
+    var unexpected = options.rest.skip(1).map((arg) => '"$arg"');
+    var arguments = pluralize("argument", unexpected.length);
+    stderr.writeln("Unexpected $arguments ${toSentence(unexpected)}.");
+    stderr.writeln(usage);
+    exitCode = USAGE_ERROR;
+    return;
+  }
+
+  new Directory(destination).createSync(recursive: true);
+
+  // TODO(nweiz): Tree-shake these libraries when issue 19896 is fixed.
+  CORE_LIBRARIES.forEach((path, output) {
+    path = p.join(sdkRoot, p.fromUri(path));
+    new File(p.join(destination, output))
+        .writeAsStringSync(stubFile(path, IMPORT_REPLACEMENTS));
+  });
+}