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

runtime/lib/math_patch.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.
 
 // A VM patch of the dart:math library.
 patch num pow(num x, num exponent) => MathNatives.pow(x, exponent);
 patch double atan2(num a, num b) => MathNatives.atan2(a, b);
 patch double sin(num x) => MathNatives.sin(x);
 patch double cos(num x) => MathNatives.cos(x);
 patch double tan(num x) => MathNatives.tan(x);
@@ skipping 42 matching lines @@
     if ((max & -max) == max) {
       // Fast case for powers of two.
       return _nextInt32() & (max - 1);
     }
 
     var rnd32;
     var result;
     do {
       rnd32 = _nextInt32();
       result = rnd32 % max;
-    } while (rnd32 - result + max >= _POW2_32);
+    } while ((rnd32 - result + max) >= _POW2_32);
     return result;
   }
 
   double nextDouble() {
-    return ((nextInt(1 << (26)) << 27) + nextInt(1 << 27)) / _POW2_53_D;
+    return ((nextInt(1 << 26) << 27) + nextInt(1 << 27)) / _POW2_53_D;
   }
 
   bool nextBool() {
-    return nextInt(1) == 0;
+    return nextInt(2) == 0;

[Ivan Posva, 2012/09/17 21:22:13]

This is the only functional change!

   }
 
   // Constants used by the algorithm or masking.
   static const _MASK_32 = (1 << 32) - 1;
   static const _MASK_64 = (1 << 64) - 1;
   static const _POW2_32 = 1 << 32;
   static const _POW2_53_D = 1.0 * (1 << 53);
 
   static const _A = 0xffffda61;
 
   // Use a singleton Random object to get a new seed if no seed was passed.
   static var _prng = null;
 
   static int _nextSeed() {
     if (_prng == null) {
       // TODO(iposva): Use system to get a random seed.
       _prng = new Random(new Date.now().millisecondsSinceEpoch);
     }
     // Trigger the PRNG once to change the internal state.
     _prng._nextInt32();
     return _prng._state;
   }
 }