Roll Observatory packages and add a roll script

unittest/lib/src/matcher/pretty_print.dart

-// Copyright (c) 2013, 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 unittest.matcher.pretty_print;
-
-import 'description.dart';
-import 'interfaces.dart';
-import 'util.dart';
-
-/// Returns a pretty-printed representation of [object].
-///
-/// If [maxLineLength] is passed, this will attempt to ensure that each line is
-/// no longer than [maxLineLength] characters long. This isn't guaranteed, since
-/// individual objects may have string representations that are too long, but
-/// most lines will be less than [maxLineLength] long.
-///
-/// If [maxItems] is passed, [Iterable]s and [Map]s will only print their first
-/// [maxItems] members or key/value pairs, respectively.
-String prettyPrint(object, {int maxLineLength, int maxItems}) {
-  String _prettyPrint(object, int indent, Set seen, bool top) {
-    // If the object is a matcher, use its description.
-    if (object is Matcher) {
-      var description = new StringDescription();
-      object.describe(description);
-      return "<$description>";
-    }
-
-    // Avoid looping infinitely on recursively-nested data structures.
-    if (seen.contains(object)) return "(recursive)";
-    seen = seen.union(new Set.from([object]));
-    String pp(child) => _prettyPrint(child, indent + 2, seen, false);
-
-    if (object is Iterable) {
-      // Print the type name for non-List iterables.
-      var type = object is List ? "" : _typeName(object) + ":";
-
-      // Truncate the list of strings if it's longer than [maxItems].
-      var strings = object.map(pp).toList();
-      if (maxItems != null && strings.length > maxItems) {
-        strings.replaceRange(maxItems - 1, strings.length, ['...']);
-      }
-
-      // If the printed string is short and doesn't contain a newline, print it
-      // as a single line.
-      var singleLine = "$type[${strings.join(', ')}]";
-      if ((maxLineLength == null ||
-              singleLine.length + indent <= maxLineLength) &&
-          !singleLine.contains("\n")) {
-        return singleLine;
-      }
-
-      // Otherwise, print each member on its own line.
-      return "$type[\n" + strings.map((string) {
-        return _indent(indent + 2) + string;
-      }).join(",\n") + "\n" + _indent(indent) + "]";
-    } else if (object is Map) {
-      // Convert the contents of the map to string representations.
-      var strings = object.keys.map((key) {
-        return '${pp(key)}: ${pp(object[key])}';
-      }).toList();
-
-      // Truncate the list of strings if it's longer than [maxItems].
-      if (maxItems != null && strings.length > maxItems) {
-        strings.replaceRange(maxItems - 1, strings.length, ['...']);
-      }
-
-      // If the printed string is short and doesn't contain a newline, print it
-      // as a single line.
-      var singleLine = "{${strings.join(", ")}}";
-      if ((maxLineLength == null ||
-              singleLine.length + indent <= maxLineLength) &&
-          !singleLine.contains("\n")) {
-        return singleLine;
-      }
-
-      // Otherwise, print each key/value pair on its own line.
-      return "{\n" + strings.map((string) {
-        return _indent(indent + 2) + string;
-      }).join(",\n") + "\n" + _indent(indent) + "}";
-    } else if (object is String) {
-      // Escape strings and print each line on its own line.
-      var lines = object.split("\n");
-      return "'" +
-          lines.map(_escapeString).join("\\n'\n${_indent(indent + 2)}'") +
-          "'";
-    } else {
-      var value = object.toString().replaceAll("\n", _indent(indent) + "\n");
-      var defaultToString = value.startsWith("Instance of ");
-
-      // If this is the top-level call to [prettyPrint], wrap the value on angle
-      // brackets to set it apart visually.
-      if (top) value = "<$value>";
-
-      // Print the type of objects with custom [toString] methods. Primitive
-      // objects and objects that don't implement a custom [toString] don't need
-      // to have their types printed.
-      if (object is num ||
-          object is bool ||
-          object is Function ||
-          object == null ||
-          defaultToString) {
-        return value;
-      } else {
-        return "${_typeName(object)}:$value";
-      }
-    }
-  }
-
-  return _prettyPrint(object, 0, new Set(), true);
-}
-
-String _indent(int length) => new List.filled(length, ' ').join('');
-
-/// Returns the name of the type of [x], or "Unknown" if the type name can't be
-/// determined.
-String _typeName(x) {
-  // dart2js blows up on some objects (e.g. window.navigator).
-  // So we play safe here.
-  try {
-    if (x == null) return "null";
-    var type = x.runtimeType.toString();
-    // TODO(nweiz): if the object's type is private, find a public superclass to
-    // display once there's a portable API to do that.
-    return type.startsWith("_") ? "?" : type;
-  } catch (e) {
-    return "?";
-  }
-}
-
-/// Returns [source] with any control characters replaced by their escape
-/// sequences.
-///
-/// This doesn't add quotes to the string, but it does escape single quote
-/// characters so that single quotes can be applied externally.
-String _escapeString(String source) => escape(source).replaceAll("'", r"\'");