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import { isTag, hasChildren } from "domhandler";
/**
* Search a node and its children for nodes passing a test function.
*
* @category Querying
* @param test Function to test nodes on.
* @param node Node to search. Will be included in the result set if it matches.
* @param recurse Also consider child nodes.
* @param limit Maximum number of nodes to return.
* @returns All nodes passing `test`.
*/
export function filter(test, node, recurse = true, limit = Infinity) {
if (!Array.isArray(node))
node = [node];
return find(test, node, recurse, limit);
}
/**
* Search an array of node and its children for nodes passing a test function.
*
* @category Querying
* @param test Function to test nodes on.
* @param nodes Array of nodes to search.
* @param recurse Also consider child nodes.
* @param limit Maximum number of nodes to return.
* @returns All nodes passing `test`.
*/
export function find(test, nodes, recurse, limit) {
const result = [];
for (const elem of nodes) {
if (test(elem)) {
result.push(elem);
if (--limit <= 0)
break;
}
if (recurse && hasChildren(elem) && elem.children.length > 0) {
const children = find(test, elem.children, recurse, limit);
result.push(...children);
limit -= children.length;
if (limit <= 0)
break;
}
}
return result;
}
/**
* Finds the first element inside of an array that matches a test function.
*
* @category Querying
* @param test Function to test nodes on.
* @param nodes Array of nodes to search.
* @returns The first node in the array that passes `test`.
* @deprecated Use `Array.prototype.find` directly.
*/
export function findOneChild(test, nodes) {
return nodes.find(test);
}
/**
* Finds one element in a tree that passes a test.
*
* @category Querying
* @param test Function to test nodes on.
* @param nodes Array of nodes to search.
* @param recurse Also consider child nodes.
* @returns The first child node that passes `test`.
*/
export function findOne(test, nodes, recurse = true) {
let elem = null;
for (let i = 0; i < nodes.length && !elem; i++) {
const checked = nodes[i];
if (!isTag(checked)) {
continue;
}
else if (test(checked)) {
elem = checked;
}
else if (recurse && checked.children.length > 0) {
elem = findOne(test, checked.children, true);
}
}
return elem;
}
/**
* @category Querying
* @param test Function to test nodes on.
* @param nodes Array of nodes to search.
* @returns Whether a tree of nodes contains at least one node passing the test.
*/
export function existsOne(test, nodes) {
return nodes.some((checked) => isTag(checked) &&
(test(checked) ||
(checked.children.length > 0 &&
existsOne(test, checked.children))));
}
/**
* Search and array of nodes and its children for elements passing a test function.
*
* Same as `find`, but limited to elements and with less options, leading to reduced complexity.
*
* @category Querying
* @param test Function to test nodes on.
* @param nodes Array of nodes to search.
* @returns All nodes passing `test`.
*/
export function findAll(test, nodes) {
var _a;
const result = [];
const stack = nodes.filter(isTag);
let elem;
while ((elem = stack.shift())) {
const children = (_a = elem.children) === null || _a === void 0 ? void 0 : _a.filter(isTag);
if (children && children.length > 0) {
stack.unshift(...children);
}
if (test(elem))
result.push(elem);
}
return result;
}
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