Roll Observatory packages and add a roll script

csslib/lib/src/messages.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 csslib.src.messages;
-
-import 'package:logging/logging.dart' show Level;
-import 'package:source_span/source_span.dart';
-
-import 'options.dart';
-
-// TODO(terry): Remove the global messages, use some object that tracks
-//              compilation state.
-
-/** The global [Messages] for tracking info/warnings/messages. */
-Messages messages;
-
-// Color constants used for generating messages.
-final String GREEN_COLOR = '\u001b[32m';
-final String RED_COLOR = '\u001b[31m';
-final String MAGENTA_COLOR = '\u001b[35m';
-final String NO_COLOR = '\u001b[0m';
-
-/** Map between error levels and their display color. */
-final Map<Level, String> _ERROR_COLORS = (() {
-  var colorsMap = new Map<Level, String>();
-  colorsMap[Level.SEVERE] = RED_COLOR;
-  colorsMap[Level.WARNING] = MAGENTA_COLOR;
-  colorsMap[Level.INFO] = GREEN_COLOR;
-  return colorsMap;
-})();
-
-/** Map between error levels and their friendly name. */
-final Map<Level, String> _ERROR_LABEL = (() {
-  var labels = new Map<Level, String>();
-  labels[Level.SEVERE] = 'error';
-  labels[Level.WARNING] = 'warning';
-  labels[Level.INFO] = 'info';
-  return labels;
-})();
-
-/** A single message from the compiler. */
-class Message {
-  final Level level;
-  final String message;
-  final SourceSpan span;
-  final bool useColors;
-
-  Message(this.level, this.message, {SourceSpan span, bool useColors: false})
-      : this.span = span,
-        this.useColors = useColors;
-
-  String toString() {
-    var output = new StringBuffer();
-    bool colors = useColors && _ERROR_COLORS.containsKey(level);
-    var levelColor = colors ? _ERROR_COLORS[level] : null;
-    if (colors) output.write(levelColor);
-    output
-      ..write(_ERROR_LABEL[level])
-      ..write(' ');
-    if (colors) output.write(NO_COLOR);
-
-    if (span == null) {
-      output.write(message);
-    } else {
-      output.write('on ');
-      output.write(span.message(message, color: levelColor));
-    }
-
-    return output.toString();
-  }
-}
-
-typedef void PrintHandler(Message obj);
-
-/**
- * This class tracks and prints information, warnings, and errors emitted by the
- * compiler.
- */
-class Messages {
-  /** Called on every error. Set to blank function to supress printing. */
-  final PrintHandler printHandler;
-
-  final PreprocessorOptions options;
-
-  final List<Message> messages = <Message>[];
-
-  Messages({PreprocessorOptions options, this.printHandler: print})
-      : options = options != null ? options : new PreprocessorOptions();
-
-  /** Report a compile-time CSS error. */
-  void error(String message, SourceSpan span) {
-    var msg = new Message(Level.SEVERE, message,
-        span: span, useColors: options.useColors);
-
-    messages.add(msg);
-
-    printHandler(msg);
-  }
-
-  /** Report a compile-time CSS warning. */
-  void warning(String message, SourceSpan span) {
-    if (options.warningsAsErrors) {
-      error(message, span);
-    } else {
-      var msg = new Message(Level.WARNING, message,
-          span: span, useColors: options.useColors);
-
-      messages.add(msg);
-    }
-  }
-
-  /** Report and informational message about what the compiler is doing. */
-  void info(String message, SourceSpan span) {
-    var msg = new Message(Level.INFO, message,
-        span: span, useColors: options.useColors);
-
-    messages.add(msg);
-
-    if (options.verbose) printHandler(msg);
-  }
-
-  /** Merge [newMessages] to this message lsit. */
-  void mergeMessages(Messages newMessages) {
-    messages.addAll(newMessages.messages);
-    newMessages.messages
-        .where((message) => message.level == Level.SEVERE || options.verbose)
-        .forEach(printHandler);
-  }
-}