jssm/src/js/tests/weighted_rand_select.js

A Javascript state machine with a simple API. Well tested, and typed with Flowtype. MIT License.

/* eslint-disable fp/no-loops */

import {describe} from 'ava-spec';

const jssm = require('../../../build/jssm.es5.js');





describe('weighted_rand_select/2', async it => {

  const fruit = [ { label: 'apple',  probability: 0.1 },
                  { label: 'orange', probability: 0.4 },
                  { label: 'banana', probability: 0.5 } ];

  const acc = {};
  for (let i=0; i<10000; ++i) {
      acc[jssm.weighted_rand_select(fruit).label] = (acc[jssm.weighted_rand_select(fruit).label] || 0) + 1;
  }

  it('banana baseline', t => t.deepEqual(true, acc.banana > 3000 ));

  it('requires an array',              t => t.throws(() => jssm.weighted_rand_select( 'not_an_array' )));
  it('requires members to be objects', t => t.throws(() => jssm.weighted_rand_select( ['not_an_obj'] )));

});

// stochable