// Copyright 2014 The Closure Library Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS-IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**
* @fileoverview Tests for goog.labs.iterable
*/
goog.module('goog.labs.iterableTest');
goog.setTestOnly('goog.labs.iterableTest');
const iterables = goog.require('goog.labs.collections.iterables');
const recordFunction = goog.require('goog.testing.recordFunction');
const testSuite = goog.require('goog.testing.testSuite');
/**
* Create an iterator starting at "start" and increments up to
* (but not including) "stop".
*/
function createRangeIterator(start, stop) {
let value = start;
const next = () => {
if (value < stop) {
return {value: value++, done: false};
}
return {value: undefined, done: true};
};
return {next: next};
}
function createRangeIterable(start, stop) {
const obj = {};
// Refer to goog.global['Symbol'] because otherwise this
// is a parse error in earlier IEs.
obj[goog.global['Symbol'].iterator] = () => createRangeIterator(start, stop);
return obj;
}
function isSymbolDefined() {
return !!goog.global['Symbol'];
}
testSuite({
testCreateRangeIterable() {
// Do not run if Symbol does not exist in this browser.
if (!isSymbolDefined()) {
return;
}
const rangeIterator = createRangeIterator(0, 3);
for (let i = 0; i < 3; i++) {
assertObjectEquals({value: i, done: false}, rangeIterator.next());
}
for (let i = 0; i < 3; i++) {
assertObjectEquals({value: undefined, done: true}, rangeIterator.next());
}
},
testForEach() {
// Do not run if Symbol does not exist in this browser.
if (!isSymbolDefined()) {
return;
}
const range = createRangeIterable(0, 3);
const callback = recordFunction();
iterables.forEach(range, callback);
callback.assertCallCount(3);
const calls = callback.getCalls();
for (let i = 0; i < calls.length; i++) {
const call = calls[i];
assertArrayEquals([i], call.getArguments());
}
},
testMap() {
// Do not run if Symbol does not exist in this browser.
if (!isSymbolDefined()) {
return;
}
const range = createRangeIterable(0, 3);
function addTwo(i) {
return i + 2;
}
const newIterable = iterables.map(range, addTwo);
const newIterator = iterables.getIterator(newIterable);
let nextObj = newIterator.next();
assertEquals(2, nextObj.value);
assertFalse(nextObj.done);
nextObj = newIterator.next();
assertEquals(3, nextObj.value);
assertFalse(nextObj.done);
nextObj = newIterator.next();
assertEquals(4, nextObj.value);
assertFalse(nextObj.done);
// Check that the iterator repeatedly signals done.
for (let i = 0; i < 3; i++) {
nextObj = newIterator.next();
assertUndefined(nextObj.value);
assertTrue(nextObj.done);
}
},
testFilter() {
function isEven(val) {
return val % 2 == 0;
}
const range = createRangeIterable(0, 6);
const newIterable = iterables.filter(range, isEven);
const newIterator = iterables.getIterator(newIterable);
let nextObj = newIterator.next();
assertEquals(0, nextObj.value);
assertFalse(nextObj.done);
nextObj = newIterator.next();
assertEquals(2, nextObj.value);
assertFalse(nextObj.done);
nextObj = newIterator.next();
assertEquals(4, nextObj.value);
assertFalse(nextObj.done);
// Check that the iterator repeatedly signals done.
for (let i = 0; i < 3; i++) {
nextObj = newIterator.next();
assertUndefined(nextObj.value);
assertTrue(nextObj.done);
}
}
});