Adjust types in SplayTree implementation and some strong tests to

tests/corelib_strong/set_test.dart

 // Copyright (c) 2011, 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 set_test;
 
 import 'package:expect/expect.dart';
 import "dart:collection";
 
 void testMain(Set create()) {
@@ skipping 251 matching lines @@
   Expect.isFalse(set.remove("not an it"));
   Expect.isFalse(set.containsAll(["Not an int", "Also no an int"]));
 
   testLength(4, set);
   set.removeAll(["Not an int", 999, "Also no an int"]);
   testLength(3, set);
   set.retainAll(["Not an int", 0, "Also no an int"]);
   testLength(1, set);
 }
 
-void testRetainWhere(Set create([equals, hashCode, validKey, compare])) {
+void testRetainWhere(
+    Set<CE> create(
+        [CEEq equals, CEHash hashCode, ValidKey validKey, CECompare compare])) {
   // The retainWhere method must not collapse the argument Iterable
   // in a way that doesn't match the equality of the set.
   // It must not throw away equal elements that are different in the
   // equality of the set.
   // It must not consider objects to be not there if they are equal
   // in the equality of the set.
 
   // If set equality is natural equality, using different but equal objects
   // must work. Can't use an identity set internally (as was done at some point
   // during development).
-  Set set = create();
+  var set = create();
   set.addAll([new CE(0), new CE(1), new CE(2)]);
   Expect.equals(3, set.length); // All different.
   set.retainAll([new CE(0), new CE(2)]);
   Expect.equals(2, set.length);
   Expect.isTrue(set.contains(new CE(0)));
   Expect.isTrue(set.contains(new CE(2)));
 
   // If equality of set is identity, we can't internally use a non-identity
   // based set because it might throw away equal objects that are not identical.
   var elems = [new CE(0), new CE(1), new CE(2), new CE(0)];
@@ skipping 64 matching lines @@
 
   intersection = set1.intersection(set3);
   testLength(0, intersection);
 }
 
 // Objects that are equal based on data.
 class CE implements Comparable<CE> {
   final int id;
   const CE(this.id);
   int get hashCode => id;
-  bool operator ==(Object other) => other is CE && id == (other as CE).id;
+  bool operator ==(Object other) => other is CE && id == other.id;
   int compareTo(CE other) => id - other.id;
   String toString() => "CE($id)";
 }
 
 typedef int CECompare(CE e1, CE e2);
+typedef int CEHash(CE e1);
+typedef bool CEEq(CE e1, CE e2);
+typedef bool ValidKey(Object o);
 // Equality of Id objects based on id modulo value.
-Function customEq(int mod) => (CE e1, CE e2) => ((e1.id - e2.id) % mod) == 0;
-Function customHash(int mod) => (CE e) => e.id % mod;
+CEEq customEq(int mod) => (CE e1, CE e2) => ((e1.id - e2.id) % mod) == 0;
+CEHash customHash(int mod) => (CE e) => e.id % mod;
 CECompare customCompare(int mod) =>
     (CE e1, CE e2) => (e1.id % mod) - (e2.id % mod);
 bool validKey(Object o) => o is CE;
 final customId = new Map<dynamic, dynamic>.identity();
 int counter = 0;
 int identityCompare(e1, e2) {
   if (identical(e1, e2)) return 0;
   int i1 = customId.putIfAbsent(e1, () => ++counter);
   int i2 = customId.putIfAbsent(e2, () => ++counter);
   return i1 - i2;
@@ skipping 144 matching lines @@
 
   testCESetFrom(
       (x) => new SplayTreeSet<CE>.from(x, customCompare(20), validKey));
   testCESetFrom((x) => new SplayTreeSet<CE>.from(x, identityCompare));
 
   testASetFrom((x) => new Set<A>.from(x));
   testASetFrom((x) => new HashSet<A>.from(x));
   testASetFrom((x) => new LinkedHashSet<A>.from(x));
   testASetFrom((x) => new SplayTreeSet<A>.from(x, identityCompare));
 }