mathjs/test/function/construction/select.test.js

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser and offers an integrated solution to work with numbers, big numbers, complex numbers, units, and matrices.

var assert = require('assert'),
    math = require('../../../index'),
    Selector = math.chaining.Selector;

describe('select', function() {

  it ('should construct a selector', function () {
    assert.ok(math.select(45) instanceof Selector);
    assert.ok(math.select(math.complex(2,3)) instanceof Selector);
    assert.ok(math.select() instanceof Selector);
  });

});