1 /* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 const { setTimeout } = require('sdk/timers');
7 const utils = require('sdk/lang/functional');
8 const { invoke, defer, partial, compose, memoize, once, is, isnt,
9 delay, wrap, curry, chainable, field, query, isInstance, debounce, throttle
11 const { LoaderWithHookedConsole } = require('sdk/test/loader');
13 exports['test forwardApply'] = function(assert) {
14 function sum(b, c) { return this.a + b + c; }
15 assert.equal(invoke(sum, [2, 3], { a: 1 }), 6,
16 'passed arguments and pseoude-variable are used');
18 assert.equal(invoke(sum.bind({ a: 2 }), [2, 3], { a: 1 }), 7,
19 'bounded `this` pseoudo variable is used');
22 exports['test deferred function'] = function(assert, done) {
25 assert.ok(nextTurn, 'enqueued is called in next turn of event loop');
26 assert.equal(this.a + b + c, 6,
27 'passed arguments an pseoude-variable are used');
31 let fixture = { a: 1, method: defer(sum) };
36 exports['test partial function'] = function(assert) {
37 function sum(b, c) { return this.a + b + c; }
41 foo.sum7 = partial(sum, 7);
42 foo.sum8and4 = partial(sum, 8, 4);
44 assert.equal(foo.sum7(2), 14, 'partial one arguments works');
46 assert.equal(foo.sum8and4(), 17, 'partial both arguments works');
49 exports["test curry defined numeber of arguments"] = function(assert) {
50 var sum = curry(function(a, b, c) {
54 assert.equal(sum(2, 2, 1), 5, "sum(2, 2, 1) => 5");
55 assert.equal(sum(2, 4)(1), 7, "sum(2, 4)(1) => 7");
56 assert.equal(sum(2)(4, 2), 8, "sum(2)(4, 2) => 8");
57 assert.equal(sum(2)(4)(3), 9, "sum(2)(4)(3) => 9");
60 exports['test compose'] = function(assert) {
61 let greet = function(name) { return 'hi: ' + name; };
62 let exclaim = function(sentence) { return sentence + '!'; };
64 assert.equal(compose(exclaim, greet)('moe'), 'hi: moe!',
65 'can compose a function that takes another');
67 assert.equal(compose(greet, exclaim)('moe'), 'hi: moe!',
68 'in this case, the functions are also commutative');
72 greet: compose(function exclaim(sentence) {
73 return sentence + '!';
75 return 'hi : ' + title + ' ' + this.name;
79 assert.equal(target.greet('Mr'), 'hi : Mr Joe!',
80 'this can be passed in');
81 assert.equal(target.greet.call({ name: 'Alex' }, 'Dr'), 'hi : Dr Alex!',
82 'this can be applied');
84 let single = compose(function(value) {
85 return value + ':suffix';
88 assert.equal(single('text'), 'text:suffix', 'works with single function');
90 let identity = compose();
91 assert.equal(identity('bla'), 'bla', 'works with zero functions');
94 exports['test wrap'] = function(assert) {
95 let greet = function(name) { return 'hi: ' + name; };
96 let backwards = wrap(greet, function(f, name) {
97 return f(name) + ' ' + name.split('').reverse().join('');
100 assert.equal(backwards('moe'), 'hi: moe eom',
101 'wrapped the saluation function');
103 let inner = function () { return 'Hello '; };
106 hi: wrap(inner, function(f) { return f() + this.name; })
109 assert.equal(target.hi(), 'Hello Matteo', 'works with this');
112 let wrapped = wrap(noop, function(f) {
113 return Array.slice(arguments);
116 let actual = wrapped([ 'whats', 'your' ], 'vector', 'victor');
117 assert.deepEqual(actual, [ noop, ['whats', 'your'], 'vector', 'victor' ],
118 'works with fancy stuff');
121 exports['test memoize'] = function(assert) {
122 const fib = n => n < 2 ? n : fib(n - 1) + fib(n - 2);
123 let fibnitro = memoize(fib);
125 assert.equal(fib(10), 55,
126 'a memoized version of fibonacci produces identical results');
127 assert.equal(fibnitro(10), 55,
128 'a memoized version of fibonacci produces identical results');
130 function o(key, value) { return value; }
131 let oo = memoize(o), v1 = {}, v2 = {};
134 assert.equal(oo(1, v1), v1, 'returns value back');
135 assert.equal(oo(1, v2), v1, 'memoized by a first argument');
136 assert.equal(oo(2, v2), v2, 'returns back value if not memoized');
137 assert.equal(oo(2), v2, 'memoized new value');
138 assert.notEqual(oo(1), oo(2), 'values do not override');
139 assert.equal(o(3, v2), oo(2, 3), 'returns same value as un-memoized');
141 let get = memoize(function(attribute) { return this[attribute]; });
142 let target = { name: 'Bob', get: get };
144 assert.equal(target.get('name'), 'Bob', 'has correct `this`');
145 assert.equal(target.get.call({ name: 'Jack' }, 'name'), 'Bob',
147 assert.equal(get('name'), 'Bob', 'once memoized can be called without this');
150 exports['test delay'] = function(assert, done) {
153 assert.ok(delayed, 'delayed the function');
159 exports['test delay with this'] = function(assert, done) {
161 delay.call(context, function(name) {
162 assert.equal(this, context, 'this was passed in');
163 assert.equal(name, 'Tom', 'argument was passed in');
168 exports['test once'] = function(assert) {
170 let increment = once(function() { n ++; });
175 assert.equal(n, 1, 'only incremented once');
179 update: once(function() {
180 return this.state ++;
187 assert.equal(target.state, 1, 'this was passed in and called only once');
190 exports['test once with argument'] = function(assert) {
192 let increment = once(a => n++);
197 assert.equal(n, 1, 'only incremented once');
202 assert.equal(n, 1, 'only incremented once');
205 exports['test complement'] = assert => {
206 let { complement } = require("sdk/lang/functional");
208 let isOdd = x => Boolean(x % 2);
210 assert.equal(isOdd(1), true);
211 assert.equal(isOdd(2), false);
213 let isEven = complement(isOdd);
215 assert.equal(isEven(1), false);
216 assert.equal(isEven(2), true);
219 let isFoo = function() { return this === foo; };
220 let insntFoo = complement(isFoo);
222 assert.equal(insntFoo.call(foo), false);
223 assert.equal(insntFoo.call({}), true);
226 exports['test constant'] = assert => {
227 let { constant } = require("sdk/lang/functional");
229 let one = constant(1);
231 assert.equal(one(1), 1);
232 assert.equal(one(2), 1);
235 exports['test apply'] = assert => {
236 let { apply } = require("sdk/lang/functional");
238 let dashify = (...args) => args.join("-");
240 assert.equal(apply(dashify, 1, [2, 3]), "1-2-3");
241 assert.equal(apply(dashify, "a"), "a");
242 assert.equal(apply(dashify, ["a", "b"]), "a-b");
243 assert.equal(apply(dashify, ["a", "b"], "c"), "a,b-c");
244 assert.equal(apply(dashify, [1, 2], [3, 4]), "1,2-3-4");
247 exports['test flip'] = assert => {
248 let { flip } = require("sdk/lang/functional");
250 let append = (left, right) => left + " " + right;
251 let prepend = flip(append);
253 assert.equal(append("hello", "world"), "hello world");
254 assert.equal(prepend("hello", "world"), "world hello");
256 let wrap = function(left, right) {
257 return left + " " + this + " " + right;
259 let invertWrap = flip(wrap);
261 assert.equal(wrap.call("@", "hello", "world"), "hello @ world");
262 assert.equal(invertWrap.call("@", "hello", "world"), "world @ hello");
264 let reverse = flip((...args) => args);
266 assert.deepEqual(reverse(1, 2, 3, 4), [4, 3, 2, 1]);
267 assert.deepEqual(reverse(1), [1]);
268 assert.deepEqual(reverse(), []);
270 // currying still works
271 let prependr = curry(prepend);
273 assert.equal(prependr("hello", "world"), "world hello");
274 assert.equal(prependr("hello")("world"), "world hello");
277 exports["test when"] = assert => {
278 let { when } = require("sdk/lang/functional");
280 let areNums = (...xs) => xs.every(x => typeof(x) === "number");
282 let sum = when(areNums, (...xs) => xs.reduce((y, x) => x + y, 0));
284 assert.equal(sum(1, 2, 3), 6);
285 assert.equal(sum(1, 2, "3"), undefined);
287 let multiply = when(areNums,
288 (...xs) => xs.reduce((y, x) => x * y, 1),
291 assert.equal(multiply(2), 2);
292 assert.equal(multiply(2, 3), 6);
293 assert.deepEqual(multiply(2, "4"), [2, "4"]);
295 function Point(x, y) {
300 let isPoint = x => x instanceof Point;
302 let inc = when(isPoint, ({x, y}) => new Point(x + 1, y + 1));
304 assert.equal(inc({}), undefined);
305 assert.deepEqual(inc(new Point(0, 0)), { x: 1, y: 1 });
307 let axis = when(isPoint,
308 ({ x, y }) => [x, y],
311 assert.deepEqual(axis(new Point(1, 4)), [1, 4]);
312 assert.deepEqual(axis({ foo: "bar" }), [0, 0]);
315 exports["test chainable"] = function(assert) {
316 let Player = function () { this.volume = 5; };
318 setBand: chainable(function (band) { return (this.band = band); }),
319 incVolume: chainable(function () { return this.volume++; })
321 let player = new Player();
323 .setBand('Animals As Leaders')
324 .incVolume().incVolume().incVolume().incVolume().incVolume().incVolume();
326 assert.equal(player.band, 'Animals As Leaders', 'passes arguments into chained');
327 assert.equal(player.volume, 11, 'accepts no arguments in chain');
330 exports["test field"] = assert => {
331 let Num = field("constructor", 0);
332 assert.equal(Num.name, Number.name);
333 assert.ok(typeof(Num), "function");
338 [field("foo", { foo: 1 }), 1],
339 [field("foo")({ foo: 1 }), 1],
340 [field("bar", {}), undefined],
341 [field("bar")({}), undefined],
342 [field("hey", undefined), undefined],
343 [field("hey")(undefined), undefined],
344 [field("how", null), null],
345 [field("how")(null), null],
347 [x(undefined), undefined],
351 ].forEach(([actual, expected]) => assert.equal(actual, expected));
354 exports["test query"] = assert => {
355 let Num = query("constructor", 0);
356 assert.equal(Num.name, Number.name);
357 assert.ok(typeof(Num), "function");
360 let xy = query("x.y");
363 [query("foo", { foo: 1 }), 1],
364 [query("foo")({ foo: 1 }), 1],
365 [query("foo.bar", { foo: { bar: 2 } }), 2],
366 [query("foo.bar")({ foo: { bar: 2 } }), 2],
367 [query("foo.bar", { foo: 1 }), undefined],
368 [query("foo.bar")({ foo: 1 }), undefined],
370 [x(undefined), undefined],
375 [xy(undefined), undefined],
377 [xy({ x: 1 }), undefined],
378 [xy({ x: 2 }), undefined],
379 [xy({ x: { y: 1 } }), 1],
380 [xy({ x: { y: 2 } }), 2]
381 ].forEach(([actual, expected]) => assert.equal(actual, expected));
384 exports["test isInstance"] = assert => {
387 let isX = isInstance(X);
390 isInstance(X, new X()),
391 isInstance(X)(new X()),
392 !isInstance(X, new Y()),
393 !isInstance(X)(new Y()),
396 ].forEach(x => assert.ok(x));
399 exports["test is"] = assert => {
401 assert.deepEqual([ 1, 0, 1, 0, 1 ].map(is(1)),
402 [ true, false, true, false, true ],
403 "is can be partially applied");
406 assert.ok(!is({}, {}));
407 assert.ok(is()(1)()(1), "is is curried");
408 assert.ok(!is()(1)()(2));
411 exports["test isnt"] = assert => {
413 assert.deepEqual([ 1, 0, 1, 0, 1 ].map(isnt(0)),
414 [ true, false, true, false, true ],
415 "is can be partially applied");
417 assert.ok(!isnt(1, 1));
418 assert.ok(isnt({}, {}));
419 assert.ok(!isnt()(1)()(1));
420 assert.ok(isnt()(1)()(2));
423 exports["test debounce"] = (assert, done) => {
425 let fn = debounce(() => counter++, 100);
427 new Array(10).join(0).split("").forEach(fn);
429 assert.equal(counter, 0, "debounce does not fire immediately");
431 assert.equal(counter, 1, "function called after wait time");
434 assert.equal(counter, 2, "function able to be called again after wait");
440 exports["test throttle"] = (assert, done) => {
443 let atleast100ms = false;
444 let throttledFn = throttle(() => {
447 assert.equal(attempt, 10, "called twice, but attempted 10 times");
451 assert.ok(atleast100ms, "atleast 100ms have passed");
452 assert.equal(attempt, 11, "called third, waits for delay to happen");
456 let fn = () => ++attempt && throttledFn();
458 setTimeout(() => atleast100ms = true, 100);
460 new Array(11).join(0).split("").forEach(fn);
463 require('test').run(exports);