pointfree-fantasy/test/monoids.js

Point free wrappers for fantasy land js.

require('../pointfree').expose(global)


var assert = require("assert")
  , quickCheckLaws = require('./helper').quickCheckLaws
  , curry = require('lodash.curry')
  , claire = require('claire')
  , _ = claire.data
  , asGenerator = claire.asGenerator
  , monoids = require('../instances/monoids')
  , forAll = claire.forAll
  ;

var _stubFn = function() { return function() { return _.Str.next().value }; };
var FunGen = asGenerator(_stubFn)

describe('Monoids', function(){
  it('gets the max', function() {
    assert.equal(monoids.getResult(mappend(monoids.Max(12), monoids.Max(20))), 20)
  });

  it('gets the min', function() {
    assert.equal(monoids.getResult(mappend(monoids.Min(12), monoids.Min(20))), 12)
  });

  it('gets the sum', function() {
    assert.equal(monoids.getResult(mappend(monoids.Sum(12), monoids.Sum(20))), 32)
  });

  it('gets the product', function() {
    assert.equal(monoids.getResult(mappend(monoids.Product(2), monoids.Product(20))), 40)
  });

  it('gets the disjunction', function() {
    assert.equal(monoids.getResult(mappend(monoids.Any(true), monoids.Any(false))), true)
    assert.equal(monoids.getResult(mappend(monoids.Any(false), monoids.Any(false))), false)
  });

  it('gets the conjunction', function() {
    assert.equal(monoids.getResult(mconcat([monoids.All(true), monoids.All(false)])), false)
    assert.equal(monoids.getResult(mappend(monoids.All(true), monoids.All(true))), true)
  });

  it('runs the functions then gets the conjuction', function() {
      var f = function(x) { return monoids.Any(x > 1); }
        , g = function(y) { return monoids.Any(y > 2); }
        ;

    // var t = compose(monoids.getResult, monoids.mconcat, fmap(monoids.All), mconcat([f, g]))
    // assert.equal(t(2, 3), false)
    assert.deepEqual(mconcat([f, g])(4, 6), monoids.Any(true))
    assert.deepEqual(mconcat([f, g])(0, 0), monoids.Any(false))
  });

});