- Fix the implementation of Random.nextBool() and add test.

tests/lib/math/coin_test.dart

Index: tests/lib/math/coin_test.dart
===================================================================
--- tests/lib/math/coin_test.dart	(revision 0)
+++ tests/lib/math/coin_test.dart	(revision 0)
@@ -0,0 +1,30 @@
+// 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.
+
+// Test that the default PRNG does converge towards Pi when doing a Monte Carlo

[kasperl, 2012/09/18 06:24:30]

Update comment?

[Ivan Posva, 2012/09/18 12:49:16]

https://codereview.chromium.org/10948008

+// simulation.
+
+// Library tag to allow Dartium to run the test.
+#library("coin_test");
+
+#import("dart:math");
+
+main() {
+  var seed = new Random().nextInt((1<<32) - 1);
+  print("coin_test seed: $seed");
+  var rnd = new Random();
+  var heads = 0;
+  var tails = 0;
+  for (var i = 0; i < 10000; i++) {
+    if (rnd.nextBool()) {
+      heads++;
+    } else {
+      tails++;
+    }
+  }
+  print("Heads: $heads\n"
+        "Tails: $tails\n"
+        "Ratio: ${heads/tails}\n");
+  Expect.approxEquals(1.0, heads/tails, tolerance:0.1);
+}