[perl #126149] use Test; is(Mu, Mu); done-testing;

[Tokuhiro Matsuno]

# New Ticket Created by  "Tokuhiro Matsuno" 
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This code throws exception.
`use Test; is(Mu, Mu); done-testing;`

Output:
Cannot call infix:<===>(Mu, Mu); none of these signatures match:
    ($?)
    ($a, $b)
    (Int:D \a, Int:D \b)
    (int $a, int $b)
    (Num:D \a, Num:D \b)
    (Num $ where { ... }, Num $ where { ... })
    (num $a, num $b --> Bool)
    (Str:D \a, Str:D \b --> Bool)
    (str $a, str $b --> Bool)
    (Rational:D \a, Rational:D \b --> Bool)
    (Complex:D \a, Complex:D \b --> Bool)
  in sub is at lib/Test.pm:119
  in block <unit> at <unknown file>:1

But I guess it shouldn't throw exception(or show more descriptive message).

This is perl6 version 2015.09-55-gc189c7e built on MoarVM version 
2015.09-4-g002edea