Roll Observatory packages and add a roll script

packages/polymer/bin/new_element.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.
+
+/// Script to create boilerplate for a Polymer element.
+/// Produces .dart and .html files for the element.
+///
+/// Run this script with pub run:
+///
+///     pub run polymer:new_element element-name [-o output_dir]
+///
+library polymer.bin.new_element;
+
+import 'dart:io';
+import 'package:args/args.dart';
+import 'package:path/path.dart' as path show absolute, dirname, join, split;
+import 'package:polymer/html_element_names.dart';
+
+void printUsage(ArgParser parser) {
+  print('pub run polymer:new_element [-o output_dir] [-e super-element] '
+      'element-name');
+  print(parser.getUsage());
+}
+
+void main(List<String> args) {
+  var parser = new ArgParser(allowTrailingOptions: true);
+
+  parser.addOption('output-dir', abbr: 'o', help: 'Output directory');
+  parser.addOption('extends',
+      abbr: 'e',
+      help: 'Extends polymer-element or DOM element (e.g., div, span)');
+  parser.addFlag('help', abbr: 'h');
+
+  var options, element;
+  try {
+    options = parser.parse(args);
+    if (options['help']) {
+      printUsage(parser);
+      return;
+    }
+    if (options.rest == null || options.rest.isEmpty) {
+      throw new FormatException('No element specified');
+    }
+    element = options.rest[0];
+    if (!_isPolymerElement(element)) {
+      throw new FormatException('Must specify polymer-element to create.\n'
+          'polymer-element must be all lowercase with at least 1 hyphen.');
+    }
+  } catch (e) {
+    print('$e\n');
+    printUsage(parser);
+    exitCode = 1;
+    return;
+  }
+
+  var outputDir, startDir;
+
+  var outputPath = options['output-dir'];
+
+  if (outputPath == null) {
+    if ((new File('pubspec.yaml')).existsSync()) {
+      print('When creating elements in root directory of package, '
+          '-o <dir> must be specified');
+      exitCode = 1;
+      return;
+    }
+    outputDir = (new Directory('.')).resolveSymbolicLinksSync();
+  } else {
+    var outputDirLocation = new Directory(outputPath);
+    if (!outputDirLocation.existsSync()) {
+      outputDirLocation.createSync(recursive: true);
+    }
+    outputDir = (new Directory(outputPath)).resolveSymbolicLinksSync();
+  }
+
+  var pubspecDir = _findDirWithFile(outputDir, 'pubspec.yaml');
+
+  if (pubspecDir == null) {
+    print('Could not find pubspec.yaml when walking up from $outputDir');
+    exitCode = 1;
+    return;
+  }
+
+  var length = path.split(pubspecDir).length;
+  var distanceToPackageRoot = path.split(outputDir).length - length;
+
+  // See dartbug.com/20076 for the algorithm used here.
+  if (distanceToPackageRoot > 0) {
+    if (path.split(outputDir)[length] == 'lib') {
+      distanceToPackageRoot++;
+    } else {
+      distanceToPackageRoot--;
+    }
+  }
+
+  var superElement = options['extends'];
+
+  if ((superElement == null) ||
+      _isDOMElement(superElement) ||
+      _isPolymerElement(superElement)) {
+    try {
+      _createBoilerPlate(
+          element, options['extends'], outputDir, distanceToPackageRoot);
+    } on Exception catch (e, t) {
+      print('Error creating files in $outputDir');
+      print('$e $t');
+      exitCode = 1;
+      return;
+    }
+  } else {
+    if (superElement.contains('-')) {
+      print('Extending invalid element "$superElement". Polymer elements '
+          'may contain only lowercase letters at least one hyphen.');
+    } else {
+      print('Extending invalid element "$superElement". $superElement is not '
+          ' a builtin DOM type.');
+    }
+    exitCode = 1;
+    return;
+  }
+
+  return;
+}
+
+String _findDirWithFile(String dir, String filename) {
+  while (!new File(path.join(dir, filename)).existsSync()) {
+    var parentDir = path.dirname(dir);
+    // If we reached root and failed to find it, bail.
+    if (parentDir == dir) return null;
+    dir = parentDir;
+  }
+  return dir;
+}
+
+bool _isDOMElement(String element) => (HTML_ELEMENT_NAMES[element] != null);
+
+bool _isPolymerElement(String element) {
+  return element.contains('-') && (element.toLowerCase() == element);
+}
+
+String _toCamelCase(String s) {
+  return s[0].toUpperCase() + s.substring(1);
+}
+
+void _createBoilerPlate(String element, String superClass, String directory,
+    int distanceToPackageRoot) {
+  var segments = element.split('-');
+  var capitalizedName = segments.map((e) => _toCamelCase(e)).join('');
+  var underscoreName = element.replaceAll('-', '_');
+  var pathToPackages = '../' * distanceToPackageRoot;
+
+  bool superClassIsPolymer =
+      (superClass == null ? false : _isPolymerElement(superClass));
+
+  var classDeclaration = '';
+  var importDartHtml = '';
+  var polymerCreatedString = '';
+  var extendsElementString = '';
+  var shadowString = '';
+
+  if (superClass == null) {
+    classDeclaration = '\nclass $capitalizedName extends PolymerElement {';
+  } else if (superClassIsPolymer) {
+    // The element being extended is a PolymerElement.
+    var camelSuperClass =
+        superClass.split('-').map((e) => _toCamelCase(e)).join('');
+    classDeclaration = 'class $capitalizedName extends $camelSuperClass {';
+    extendsElementString = ' extends="$superClass"';
+    shadowString = '\n    <!-- Render extended element\'s Shadow DOM here -->\n'
+        '    <shadow>\n    </shadow>';
+  } else {
+    // The element being extended is a DOM Class.
+    importDartHtml = "import 'dart:html';\n";
+    classDeclaration =
+        'class $capitalizedName extends ${HTML_ELEMENT_NAMES[superClass]} '
+        'with Polymer, Observable {';
+    polymerCreatedString = '\n    polymerCreated();';
+    extendsElementString = ' extends="$superClass"';
+  }
+
+  String html = '''  
+<!-- import polymer-element's definition -->
+<link rel="import" href="${pathToPackages}packages/polymer/polymer.html">
+
+<polymer-element name="$element"$extendsElementString>
+  <template>
+    <style>
+      :host {
+        display: block;
+      }
+    </style>$shadowString
+    <!-- Template content here -->
+  </template>
+  <script type="application/dart" src="${underscoreName}.dart"></script>
+</polymer-element>
+''';
+
+  String htmlFile = path.join(directory, underscoreName + '.html');
+  new File(htmlFile).writeAsStringSync(html);
+
+  String dart = '''
+${importDartHtml}import 'package:polymer/polymer.dart';
+
+/**
+ * A Polymer $element element.
+ */
+@CustomTag('$element')
+$classDeclaration
+
+  /// Constructor used to create instance of ${capitalizedName}.
+  ${capitalizedName}.created() : super.created() {$polymerCreatedString
+  }
+
+  /*
+   * Optional lifecycle methods - uncomment if needed.
+   *
+
+  /// Called when an instance of $element is inserted into the DOM.
+  attached() {
+    super.attached();
+  }
+
+  /// Called when an instance of $element is removed from the DOM.
+  detached() {
+    super.detached();
+  }
+
+  /// Called when an attribute (such as  a class) of an instance of
+  /// $element is added, changed, or removed.
+  attributeChanged(String name, String oldValue, String newValue) {
+  }
+
+  /// Called when $element has been fully prepared (Shadow DOM created,
+  /// property observers set up, event listeners attached).
+  ready() {
+  }
+   
+  */
+  
+}
+''';
+
+  String dartFile = path.join(directory, underscoreName + '.dart');
+  new File(dartFile).writeAsStringSync(dart);
+
+  print('Successfully created:');
+  print('  ' + path.absolute(path.join(directory, underscoreName + '.dart')));
+  print('  ' + path.absolute(path.join(directory, underscoreName + '.html')));
+}