text: const mathlib = require('../src');
  const assert = require('assert');
  
  describe('constrain', function() {
    it('should return 5', function() {
      assert.equal(mathlib.constrain(10, 0, 5), 5);
    });
  });
  
  describe('map_constrain', function() {
    it('should return 10', function() {
      assert.equal(mathlib.map_constrain(10, 0, 5, 5, 10), 10);
    });
    it('should return 10', function() {
      assert.equal(mathlib.map_constrain(10, 0, 5, 10, 5), 5);
    });
  });
  
  describe('map', function() {
    it('should return 10', function() {
      assert.equal(mathlib.map(5, 0, 5, 0, 10), 10);
    });
  });
  
  describe('round_dec', function() {
    it('should return 1.2', function() {
      assert.equal(mathlib.round_dec(1.23456, 1), 1.2);
    });
  });
  
  