[MacRuby] #1446: Add additional diagnostic info when assertion fails in RoxorVM::pop_current_exception

[MacRuby]

#1446: Add additional diagnostic info when assertion fails in
RoxorVM::pop_current_exception
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 Reporter:  msabramo@…          |       Owner:  lsansonetti@…        
     Type:  enhancement         |      Status:  new                  
 Priority:  minor               |   Milestone:                       
Component:  MacRuby             |    Keywords:                       
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 I've discovered that it's not difficult to make MacRuby crash by doing
 things that it doesn't like.

 For instance, right now I'm debugging this crash in my app:
 `Assertion failed: ((size_t)pos < current_exceptions.size()), function
 pop_current_exception, file vm.cpp, line 3596.`

 From a little big of digging around, I gather that this is probably coming
 from in `RoxorVM::pop_current_exception` in
 https://github.com/MacRuby/MacRuby/blob/master/vm.cpp#L3600

 I propose to add more information about `current_exceptions` when this
 assertion fails.

 I will work on this and submit a GitHub pull request...

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Ticket URL: <http://www.macruby.org/trac/ticket/1446>
MacRuby <http://macruby.org/>