Inf.Rat == Rational bug

[b2gills]

The Problem

The &infix:<==>(Rational:D \a, Rational:D \b) candidate doesn't handle Inf.Rat properly.

1/0 == 1/3; # True
1/3 == 1/0; # True

Since both Inf.Rat and NaN.Rat have zero for a denominator, the following gets to the code marked with # NaN != NaN.

multi sub infix:<==>(Rational:D \a, Rational:D \b) {
    nqp::hllbool(
      nqp::isfalse(a.denominator) || nqp::isfalse(b.denominator)
        ?? nqp::iseq_I(a.numerator, b.numerator)
          && nqp::istrue(a.numerator) # NaN != NaN
        !! nqp::iseq_I(
            nqp::mul_I(a.numerator, b.denominator, Int),
            nqp::mul_I(b.numerator, a.denominator, Int)))
}

[lizmat]

Fixed with c11e7e6 .

[lizmat]

Tests added with Raku/roast@6feffac83c