Big merge from experimental to bleeding edge.

tests/corelib/iterable_join_test.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.
+
+class IC {
+  int count = 0;
+  String toString() => "${count++}";
+}
+
+testJoin(String expect, Iterable iterable, [String separator]) {
+  Expect.equals(expect, iterable.join(separator));
+}
+
+testCollections() {
+  testJoin("", [], ",");
+  testJoin("", [], "");
+  testJoin("", []);
+  testJoin("", new Set(), ",");
+  testJoin("", new Set(), "");
+  testJoin("", new Set());
+
+  testJoin("42", [42], ",");
+  testJoin("42", [42], "");
+  testJoin("42", [42]);
+  testJoin("42", new Set()..add(42), ",");
+  testJoin("42", new Set()..add(42), "");
+  testJoin("42", new Set()..add(42));
+
+  testJoin("a,b,c,d", ["a", "b", "c", "d"], ",");
+  testJoin("abcd", ["a", "b", "c", "d"], "");
+  testJoin("abcd", ["a", "b", "c", "d"]);
+  testJoin("null,b,c,d", [null,"b","c","d"], ",");
+  testJoin("1,2,3,4", [1, 2, 3, 4], ",");
+  var ic = new IC();
+  testJoin("0,1,2,3", [ic, ic, ic, ic], ",");
+
+  var set = new Set()..add(1)..add(2)..add(3);
+  var perm = new Set()..add("123")..add("132")..add("213")
+                      ..add("231")..add("312")..add("321");
+  var setString = set.join();
+  Expect.isTrue(perm.contains(setString), "set: $setString");
+
+  void testArray(array) {
+    testJoin("1,3,5,7,9", array.where((i) => i.isOdd), ",");
+    testJoin("0,2,4,6,8,10,12,14,16,18", array.mappedBy((i) => i * 2), ",");
+    testJoin("5,6,7,8,9", array.skip(5), ",");
+    testJoin("5,6,7,8,9", array.skipWhile((i) => i < 5), ",");
+    testJoin("0,1,2,3,4", array.take(5), ",");
+    testJoin("0,1,2,3,4", array.takeWhile((i) => i < 5), ",");
+  }
+  testArray([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
+  var fixedArray = new List.fixedLength(10);
+  for (int i = 0; i < 10; i++) {
+    fixedArray[i] = i;
+  }
+  testArray(fixedArray);
+  testArray(const [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
+}
+
+main() {
+  testCollections();
+  // TODO(lrn): test scalar lists.
+}