Fix bug in internal SplayTreeIterator constructor.

tests/corelib/splay_tree_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.
 
 // Dart test for Splaytrees.
 library splay_tree_test;
 import "package:expect/expect.dart";
 import 'dart:collection';
 
 
-class SplayTreeMapTest {
+main() {
+  // Simple tests.
+  SplayTreeMap tree = new SplayTreeMap();
+  tree[1] = "first";
+  tree[3] = "third";
+  tree[5] = "fifth";
+  tree[2] = "second";
+  tree[4] = "fourth";
 
-  static testMain() {
-    SplayTreeMap tree = new SplayTreeMap();
-    tree[1] = "first";
-    tree[3] = "third";
-    tree[5] = "fifth";
-    tree[2] = "second";
-    tree[4] = "fourth";
+  var correctSolution = ["first", "second", "third", "fourth", "fifth"];
 
-    var correctSolution = ["first", "second", "third", "fourth", "fifth"];
+  tree.forEach((key, value) {
+    Expect.equals(true, key >= 1);
+    Expect.equals(true, key <= 5);
+    Expect.equals(value, correctSolution[key - 1]);
+  });
 
-    tree.forEach((key, value) {
-      Expect.equals(true, key >= 1);
-      Expect.equals(true, key <= 5);
-      Expect.equals(value, correctSolution[key - 1]);
-    });
+  for (var v in ["first", "second", "third", "fourth", "fifth"]) {
+    Expect.isTrue(tree.containsValue(v));
+  };
+  Expect.isFalse(tree.containsValue("sixth"));
 
-    for (var v in ["first", "second", "third", "fourth", "fifth"]) {
-      Expect.isTrue(tree.containsValue(v));
-    };
-    Expect.isFalse(tree.containsValue("sixth"));
+  tree[7] = "seventh";
 
-    tree[7] = "seventh";
+  Expect.equals(1, tree.firstKey());
+  Expect.equals(7, tree.lastKey());
 
-    Expect.equals(1, tree.firstKey());
-    Expect.equals(7, tree.lastKey());
+  Expect.equals(2, tree.lastKeyBefore(3));
+  Expect.equals(4, tree.firstKeyAfter(3));
 
-    Expect.equals(2, tree.lastKeyBefore(3));
-    Expect.equals(4, tree.firstKeyAfter(3));
+  Expect.equals(null, tree.lastKeyBefore(1));
+  Expect.equals(2, tree.firstKeyAfter(1));
 
-    Expect.equals(null, tree.lastKeyBefore(1));
-    Expect.equals(2, tree.firstKeyAfter(1));
+  Expect.equals(4, tree.lastKeyBefore(5));
+  Expect.equals(7, tree.firstKeyAfter(5));
 
-    Expect.equals(4, tree.lastKeyBefore(5));
-    Expect.equals(7, tree.firstKeyAfter(5));
+  Expect.equals(5, tree.lastKeyBefore(7));
+  Expect.equals(null, tree.firstKeyAfter(7));
 
-    Expect.equals(5, tree.lastKeyBefore(7));
-    Expect.equals(null, tree.firstKeyAfter(7));
+  Expect.equals(5, tree.lastKeyBefore(6));
+  Expect.equals(7, tree.firstKeyAfter(6));
 
-    Expect.equals(5, tree.lastKeyBefore(6));
-    Expect.equals(7, tree.firstKeyAfter(6));
-  }
+  regressRemoveWhere();
 }
 
-main() {
-  SplayTreeMapTest.testMain();
+void regressRemoveWhere() {
+  // Regression test. Fix in https://codereview.chromium.org/148523006/
+  var t = new SplayTreeSet();
+  t.addAll([1,3,5,7,2,4,6,8,0]);
+  var seen = new List<bool>.filled(9, false);
+  t.removeWhere((x) {
+    // Called only once per element.
+    Expect.isFalse(seen[x], "seen $x");
+    seen[x] = true;
+    return x.isOdd;
+  });
 }