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/**
* @license
* Copyright (C) 2020 The Android Open Source Project
*
* 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 Functions in this file contains some widely used
* code patterns. If you noticed a repeated code and none of the existing util
* files are appropriate for it - you can wrap the code in a function and put it
* here. If you notice that several functions can be group together - create
* a separate util file for them.
*/
/**
* Wrapper for the Object.prototype.hasOwnProperty method
*/
// eslint-disable-next-line @typescript-eslint/no-explicit-any
export function hasOwnProperty(obj: any, prop: PropertyKey) {
// Typescript rules don't allow to use obj.hasOwnProperty directly
return Object.prototype.hasOwnProperty.call(obj, prop);
}
// TODO(TS): move to common types once we have type utils
// Required for constructor signature.
// eslint-disable-next-line @typescript-eslint/no-explicit-any
export type Constructor<T> = new (...args: any[]) => T;
/**
* Use the function for compile-time checking that all possible input
* values are processed
*/
export function assertNever(obj: never, msg: string): never {
console.error(msg, obj);
throw new Error(msg);
}
/**
* Throws an error with the provided error message if the condition is false.
*/
export function check(
condition: boolean,
errorMessage: string
): asserts condition {
if (!condition) throw new Error(errorMessage);
}
/**
* Throws an error if the property is not defined.
*/
export function checkProperty(
condition: boolean,
propertyName: string
): asserts condition {
check(condition, `missing required property '${propertyName}'`);
}
/**
* Throws an error if the property is not defined.
*/
export function checkRequiredProperty<T>(
property: T,
propertyName: string
): asserts property is NonNullable<T> {
if (property === undefined || property === null) {
throw new Error(`Required property '${propertyName}' not set.`);
}
}
/**
* Throws an error if the property is not defined.
*/
export function assertIsDefined<T>(
val: T,
variableName = 'variable'
): asserts val is NonNullable<T> {
if (val === undefined || val === null) {
throw new Error(`${variableName} is not defined`);
}
}
export function queryAll<E extends Element = Element>(
el: Element,
selector: string
): NodeListOf<E> {
if (!el) throw new Error('element not defined');
const root = el.shadowRoot ?? el;
return root.querySelectorAll<E>(selector);
}
export function query<E extends Element = Element>(
el: Element | null | undefined,
selector: string
): E | undefined {
if (!el) return undefined;
if (el.shadowRoot) {
const r = el.shadowRoot.querySelector<E>(selector);
if (r) return r;
}
return el.querySelector<E>(selector) ?? undefined;
}
export function queryAndAssert<E extends Element = Element>(
el: Element | null | undefined,
selector: string
): E {
const found = query<E>(el, selector);
if (!found) throw new Error(`selector '${selector}' did not match anything'`);
return found;
}
/**
* Returns true, if both sets contain the same members.
*/
export function areSetsEqual<T>(a: Set<T>, b: Set<T>): boolean {
if (a.size !== b.size) {
return false;
}
return containsAll(a, b);
}
/**
* Returns true, if 'set' contains 'subset'.
*/
export function containsAll<T>(set: Set<T>, subSet: Set<T>): boolean {
for (const value of subSet) {
if (!set.has(value)) {
return false;
}
}
return true;
}
/**
* Add value, if the set does not contain it. Otherwise remove it.
*/
export function toggleSetMembership<T>(set: Set<T>, value: T): void {
if (set.has(value)) {
set.delete(value);
} else {
set.add(value);
}
}
export function unique<T>(item: T, index: number, array: T[]) {
return array.indexOf(item) === index;
}