web-apps/vendor/underscore/test/chaining.js
Maxim Kadushkin 741b10515d webapps added
2016-03-10 21:48:53 -03:00

66 lines
1.9 KiB
JavaScript

$(document).ready(function() {
module("Chaining");
test("map/flatten/reduce", function() {
var lyrics = [
"I'm a lumberjack and I'm okay",
"I sleep all night and I work all day",
"He's a lumberjack and he's okay",
"He sleeps all night and he works all day"
];
var counts = _(lyrics).chain()
.map(function(line) { return line.split(''); })
.flatten()
.reduce(function(hash, l) {
hash[l] = hash[l] || 0;
hash[l]++;
return hash;
}, {}).value();
ok(counts.a == 16 && counts.e == 10, 'counted all the letters in the song');
});
test("select/reject/sortBy", function() {
var numbers = [1,2,3,4,5,6,7,8,9,10];
numbers = _(numbers).chain().select(function(n) {
return n % 2 === 0;
}).reject(function(n) {
return n % 4 === 0;
}).sortBy(function(n) {
return -n;
}).value();
equal(numbers.join(', '), "10, 6, 2", "filtered and reversed the numbers");
});
test("select/reject/sortBy in functional style", function() {
var numbers = [1,2,3,4,5,6,7,8,9,10];
numbers = _.chain(numbers).select(function(n) {
return n % 2 === 0;
}).reject(function(n) {
return n % 4 === 0;
}).sortBy(function(n) {
return -n;
}).value();
equal(numbers.join(', '), "10, 6, 2", "filtered and reversed the numbers");
});
test("reverse/concat/unshift/pop/map", function() {
var numbers = [1,2,3,4,5];
numbers = _(numbers).chain()
.reverse()
.concat([5, 5, 5])
.unshift(17)
.pop()
.map(function(n){ return n * 2; })
.value();
equal(numbers.join(', '), "34, 10, 8, 6, 4, 2, 10, 10", 'can chain together array functions.');
});
test("chaining works in small stages", function() {
var o = _([1, 2, 3, 4]).chain();
deepEqual(o.filter(function(i) { return i < 3; }).value(), [1, 2]);
deepEqual(o.filter(function(i) { return i > 2; }).value(), [3, 4]);
});
});