How to use the bindings.convert function in bindings

it('should work from the native build', function(done) {
    var ttf2woff2 = require('bindings')('addon.node').convert;
    var inputContent = fs.readFileSync(__dirname + '/expected/iconsfont.ttf');
    var outputContent = ttf2woff2(inputContent);

    assert.equal(outputContent.length, 1072);
    assert.equal(outputContent[1071], 0);
    assert.deepEqual(
      outputContent,
      fs.readFileSync(__dirname + '/expected/iconsfont.woff2')
    );
    done();
  });

'use strict';

try {
  module.exports = require('bindings')('addon.node').convert;
} catch (err) {
  module.exports = require('../jssrc/index.js');
}