Bug 15965 - Random.Next([maxValue == zero]) throws DivideByZeroException
Summary: Random.Next([maxValue == zero]) throws DivideByZeroException
Status: RESOLVED FIXED
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: 3.2.x
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2013-11-06 09:45 UTC by Gabriël van der Kruijk
Modified: 2014-01-22 21:26 UTC (History)
2 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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Status:
RESOLVED FIXED

Description Gabriël van der Kruijk 2013-11-06 09:45:36 UTC
When you call:

Random r = new Random();
r.Next(0);

You'll get an exception (division by zero), should return 0:


Return Value
Type: System.Int32
A 32-bit signed integer greater than or equal to zero, and less than maxValue; that is, the range of return values ordinarily includes zero but not maxValue. However, if maxValue equals zero, maxValue is returned.

Source: http://msdn.microsoft.com/en-us/library/zd1bc8e5%28v=vs.110%29.aspx


Btw: Is it still possible to look at the source of MonoTouch somewhere? Or is that now closed?
Comment 1 Sebastien Pouliot 2014-01-22 21:26:57 UTC
That should already be fixed [1] but maybe it was not released in the version of Mono[Touch] you're using. It's hard to say without knowing the exact version numbers (in doubt please provide them* and I'll double check).

* The easiest way to get exact version information is to use the "Xamarin Studio" menu, "About Xamarin Studio" item, "Show Details" button and copy/paste the version informations (you can use the "Copy Information" button).

> Btw: Is it still possible to look at the source of MonoTouch somewhere? 

MonoTouch source code was never open/public. However a large part of the BCL (including Random [2] from mscorlib.dll) comes from the Mono project - which is open source and publicly visible on github.

[1] https://github.com/mono/mono/commit/edbcf074ce6cb21301a1a43d72f5c5b44694ac84
[2] https://github.com/mono/mono/blob/master/mcs/class/corlib/System/Random.cs