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/**
* @license
* Copyright 2020 Google Inc.
* SPDX-License-Identifier: Apache-2.0
*/
import type {ElementHandle} from '../api/ElementHandle.js';
import {QueryHandler, type QuerySelector} from '../common/QueryHandler.js';
import type {AwaitableIterable} from '../common/types.js';
import {assert} from '../util/assert.js';
import {AsyncIterableUtil} from '../util/AsyncIterableUtil.js';
interface ARIASelector {
name?: string;
role?: string;
}
const isKnownAttribute = (
attribute: string
): attribute is keyof ARIASelector => {
return ['name', 'role'].includes(attribute);
};
/**
* The selectors consist of an accessible name to query for and optionally
* further aria attributes on the form `[<attribute>=<value>]`.
* Currently, we only support the `name` and `role` attribute.
* The following examples showcase how the syntax works wrt. querying:
*
* - 'title[role="heading"]' queries for elements with name 'title' and role 'heading'.
* - '[role="image"]' queries for elements with role 'image' and any name.
* - 'label' queries for elements with name 'label' and any role.
* - '[name=""][role="button"]' queries for elements with no name and role 'button'.
*/
const ATTRIBUTE_REGEXP =
/\[\s*(?<attribute>\w+)\s*=\s*(?<quote>"|')(?<value>\\.|.*?(?=\k<quote>))\k<quote>\s*\]/g;
const parseARIASelector = (selector: string): ARIASelector => {
const queryOptions: ARIASelector = {};
const defaultName = selector.replace(
ATTRIBUTE_REGEXP,
(_, attribute, __, value) => {
assert(
isKnownAttribute(attribute),
`Unknown aria attribute "${attribute}" in selector`
);
queryOptions[attribute] = value;
return '';
}
);
if (defaultName && !queryOptions.name) {
queryOptions.name = defaultName;
}
return queryOptions;
};
/**
* @internal
*/
export class ARIAQueryHandler extends QueryHandler {
static override querySelector: QuerySelector = async (
node,
selector,
{ariaQuerySelector}
) => {
return await ariaQuerySelector(node, selector);
};
static override async *queryAll(
element: ElementHandle<Node>,
selector: string
): AwaitableIterable<ElementHandle<Node>> {
const {name, role} = parseARIASelector(selector);
yield* element.queryAXTree(name, role);
}
static override queryOne = async (
element: ElementHandle<Node>,
selector: string
): Promise<ElementHandle<Node> | null> => {
return (
(await AsyncIterableUtil.first(this.queryAll(element, selector))) ?? null
);
};
}