mathjs/test/function/arithmetic/equal.test.js

// test equal
var assert = require('assert'),
    math = require('../../../index')(),
    error = require('../../../lib/error/index'),
    bignumber = math.bignumber,
    complex = math.complex,
    matrix = math.matrix,
    unit = math.unit,
    equal = math.equal;

describe('equal', function() {

  it('should compare two numbers correctly', function() {
    assert.equal(equal(2, 3), false);
    assert.equal(equal(2, 2), true);
    assert.equal(equal(0, 0), true);
    assert.equal(equal(-2, 2), false);
  });

  it('should compare two floating point numbers correctly', function() {
    // NaN
    assert.equal(equal(Number.NaN, Number.NaN), false);
    // Infinity
    assert.equal(equal(Number.POSITIVE_INFINITY, Number.POSITIVE_INFINITY), true);
    assert.equal(equal(Number.NEGATIVE_INFINITY, Number.NEGATIVE_INFINITY), true);
    assert.equal(equal(Number.POSITIVE_INFINITY, Number.NEGATIVE_INFINITY), false);
    assert.equal(equal(Number.NEGATIVE_INFINITY, Number.POSITIVE_INFINITY), false);
    assert.equal(equal(Number.POSITIVE_INFINITY, 2.0), false);
    assert.equal(equal(2.0, Number.POSITIVE_INFINITY), false);
    assert.equal(equal(Number.NEGATIVE_INFINITY, 2.0), false);
    assert.equal(equal(2.0, Number.NEGATIVE_INFINITY), false);
    assert.equal(equal(Number.NaN, Number.POSITIVE_INFINITY), false);
    assert.equal(equal(Number.POSITIVE_INFINITY, Number.NaN), false);
    assert.equal(equal(Number.NaN, Number.NEGATIVE_INFINITY), false);
    assert.equal(equal(Number.NEGATIVE_INFINITY, Number.NaN), false);
    // floating point numbers
    assert.equal(equal(0.3 - 0.2, 0.1), true);
  });

  it('should compare two booleans', function() {
    assert.equal(equal(true, true), true);
    assert.equal(equal(true, false), false);
    assert.equal(equal(false, true), false);
    assert.equal(equal(false, false), true);
  });

  it('should compare mixed numbers and booleans', function() {
    assert.equal(equal(2, true), false);
    assert.equal(equal(1, true), true);
    assert.equal(equal(0, true), false);
    assert.equal(equal(true, 2), false);
    assert.equal(equal(true, 1), true);
    assert.equal(equal(false, 2), false);
    assert.equal(equal(false, 0), true);
  });

  it('should compare bignumbers', function() {
    assert.equal(equal(bignumber(2), bignumber(3)), false);
    assert.equal(equal(bignumber(2), bignumber(2)), true);
    assert.equal(equal(bignumber(3), bignumber(2)), false);
    assert.equal(equal(bignumber(0), bignumber(0)), true);
    assert.equal(equal(bignumber(-2), bignumber(2)), false);
  });

  it('should compare mixed numbers and bignumbers', function() {
    assert.deepEqual(equal(bignumber(2), 3), false);
    assert.deepEqual(equal(2, bignumber(2)), true);

    assert.equal(equal(1/3, bignumber(1).div(3)), true);
    assert.equal(equal(bignumber(1).div(3), 1/3), true);
  });

  it('should compare mixed booleans and bignumbers', function() {
    assert.equal(equal(bignumber(0.1), true), false);
    assert.equal(equal(bignumber(1), true), true);
    assert.equal(equal(bignumber(1), false), false);
    assert.equal(equal(false, bignumber(0)), true);
    assert.equal(equal(true, bignumber(0)), false);
  });

  it('should compare two complex numbers correctly', function() {
    assert.equal(equal(complex(2,3), complex(2,4)), false);
    assert.equal(equal(complex(2,3), complex(2,3)), true);
    assert.equal(equal(complex(1,3), complex(2,3)), false);
    assert.equal(equal(complex(1,3), complex(2,4)), false);
    assert.equal(equal(complex(2,0), 2), true);
    assert.equal(equal(complex(2,1), 2), false);
    assert.equal(equal(2, complex(2, 0)), true);
    assert.equal(equal(2, complex(2, 1)), false);
    assert.equal(equal(complex(2,0), 3), false);
  });

  it('should compare mixed complex numbers and bignumbers (downgrades to numbers)', function() {
    assert.deepEqual(equal(math.complex(6, 0), bignumber(6)), true);
    assert.deepEqual(equal(math.complex(6, -2), bignumber(6)), false);
    assert.deepEqual(equal(bignumber(6), math.complex(6, 0)), true);
    assert.deepEqual(equal(bignumber(6), math.complex(6, 4)), false);
  });

  it('should compare two units correctly', function() {
    assert.equal(equal(unit('100cm'), unit('10inch')), false);
    assert.equal(equal(unit('100cm'), unit('1m')), true);
    //assert.equal(equal(unit('12inch'), unit('1foot')), true); // round-off error :(
    //assert.equal(equal(unit('2.54cm'), unit('1inch')), true); // round-off error :(
  });

  it('should throw an error when comparing a unit with a big number', function() {
    assert.throws( function () {equal(math.unit('5 m'), bignumber(10)).toString() });
  });

  it('should throw an error when comparing a unit with a number', function() {
    assert.throws(function () {equal(unit('100cm'), 22)});
  });

  it('should throw an error for two measures of different units', function() {
    assert.throws(function () {equal(math.unit(5, 'km'), math.unit(100, 'gram'));});
  });

  it('should compare two strings correctly', function() {
    assert.equal(equal('0', 0), true);
    assert.equal(equal('Hello', 'hello'), false);
    assert.equal(equal('hello', 'hello'), true);
  });

  it('should compare a string an matrix elementwise', function() {
    assert.deepEqual(equal('B', ['A', 'B', 'C']), [false, true, false]);
    assert.deepEqual(equal(['A', 'B', 'C'], 'B'), [false, true, false]);
  });

  it('should compare two matrices correctly', function() {
    assert.deepEqual(equal([1,4,5], [3,4,5]), [false, true, true]);
    assert.deepEqual(equal([1,4,5], matrix([3,4,5])), matrix([false, true, true]));
  });

  it('should throw an error if matrices have different sizes', function() {
    assert.throws(function () {equal([1,4,5], [3,4])});
  });

  it('should throw an error in case of invalid number of arguments', function() {
    assert.throws(function () {equal(1)}, error.ArgumentsError);
    assert.throws(function () {equal(1, 2, 3)}, error.ArgumentsError);
  });

});