texmath-0.12.5: test/writer/mml/mi1.test

<<< native
[ EIdentifier "x"
, ESymbol Bin "+"
, EGrouped [ EIdentifier "a" , ESymbol Ord "/" , EIdentifier "b" ]
]
>>> mml
<?xml version='1.0' ?>
<math display="block" xmlns="http://www.w3.org/1998/Math/MathML">
  <mrow>
    <mi>x</mi>
    <mo>+</mo>
    <mrow>
      <mi>a</mi>
      <mi>/</mi>
      <mi>b</mi>
    </mrow>
  </mrow>
</math>