angular/packages/core/src/util/comparison.ts

32 lines
1.0 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {areIterablesEqual, isListLikeIterable} from './iterable';
// JS has NaN !== NaN
export function looseIdentical(a: any, b: any): boolean {
return a === b || typeof a === 'number' && typeof b === 'number' && isNaN(a) && isNaN(b);
}
export function devModeEqual(a: any, b: any): boolean {
const isListLikeIterableA = isListLikeIterable(a);
const isListLikeIterableB = isListLikeIterable(b);
if (isListLikeIterableA && isListLikeIterableB) {
return areIterablesEqual(a, b, devModeEqual);
} else {
const isAObject = a && (typeof a === 'object' || typeof a === 'function');
const isBObject = b && (typeof b === 'object' || typeof b === 'function');
if (!isListLikeIterableA && isAObject && !isListLikeIterableB && isBObject) {
return true;
} else {
return looseIdentical(a, b);
}
}
}