pkg/matcher: Reverting 36881,36896 while investigating dart2js checked crash

pkg/matcher/lib/src/utils.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 matcher.utils;
+
+/**
+ * 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) =>
+    source.split("").map(_escapeChar).join("");
+
+/** Return the escaped form of a character [ch]. */
+String _escapeChar(String ch) {
+  if (ch == "'")
+    return "\\'";
+  else if (ch == '\n')
+    return '\\n';
+  else if (ch == '\r')
+    return '\\r';
+  else if (ch == '\t')
+    return '\\t';
+  else
+    return ch;
+}
+
+/** Indent each line in [str] by two spaces. */
+String indent(String str) =>
+  str.replaceAll(new RegExp("^", multiLine: true), "  ");
+
+/** A pair of values. */
+class Pair<E, F> {
+  E first;
+  F last;
+
+  Pair(this.first, this.last);
+
+  String toString() => '($first, $last)';
+
+  bool operator ==(other) {
+    if (other is! Pair) return false;
+    return other.first == first && other.last == last;
+  }
+
+  int get hashCode => first.hashCode ^ last.hashCode;
+}
+