/**
* @license
* Copyright 2016 Google Inc.
*
* 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.
*/
goog.provide('shaka.util.ArrayUtils');
/**
* @namespace shaka.util.ArrayUtils
* @summary Array utility functions.
*/
/**
* Returns whether the two values contain the same value. This correctly
* handles comparisons involving NaN.
* @param {T} a
* @param {T} b
* @return {boolean}
* @template T
*/
shaka.util.ArrayUtils.defaultEquals = function(a, b) {
// NaN !== NaN, so we need to special case it.
if (typeof a === 'number' && typeof b === 'number' && isNaN(a) && isNaN(b)) {
return true;
}
return a === b;
};
/**
* Remove given element from array (assumes no duplicates).
* @param {!Array.<T>} array
* @param {T} element
* @template T
*/
shaka.util.ArrayUtils.remove = function(array, element) {
let index = array.indexOf(element);
if (index > -1) {
array.splice(index, 1);
}
};
/**
* Count the number of items in the list that pass the check function.
* @param {!Array.<T>} array
* @param {function(T):boolean} check
* @return {number}
* @template T
*/
shaka.util.ArrayUtils.count = function(array, check) {
let count = 0;
array.forEach(function(element) {
count += check(element) ? 1 : 0;
});
return count;
};
/**
* Determines if the given arrays contain equal elements in any order.
*
* @param {!Array.<T>} a
* @param {!Array.<T>} b
* @param {function(T, T):boolean=} compareFn
* @return {boolean}
* @template T
*/
shaka.util.ArrayUtils.hasSameElements = function(a, b, compareFn) {
if (!compareFn) {
compareFn = shaka.util.ArrayUtils.defaultEquals;
}
if (a.length != b.length) {
return false;
}
const copy = b.slice();
for (const item of a) {
const idx = copy.findIndex((other) => compareFn(item, other));
if (idx == -1) {
return false;
}
// Since order doesn't matter, just swap the last element with this one and
// then drop the last element.
copy[idx] = copy[copy.length - 1];
copy.pop();
}
return copy.length == 0;
};
/**
* Determines if the given arrays contain equal elements in the same order.
*
* @param {!Array.<T>} a
* @param {!Array.<T>} b
* @param {function(T, T):boolean=} compareFn
* @return {boolean}
* @template T
*/
shaka.util.ArrayUtils.equal = function(a, b, compareFn) {
if (!compareFn) {
compareFn = shaka.util.ArrayUtils.defaultEquals;
}
if (a.length != b.length) {
return false;
}
for (let i = 0; i < a.length; i++) {
if (!compareFn(a[i], b[i])) {
return false;
}
}
return true;
};