domutils/lib/querying.js

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.findAll = exports.existsOne = exports.findOne = exports.findOneChild = exports.find = exports.filter = void 0;
var domhandler_1 = require("domhandler");
/**
 * Search a node and its children for nodes passing a test function.
 *
 * @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`.
 */
function filter(test, node, recurse, limit) {
    if (recurse === void 0) { recurse = true; }
    if (limit === void 0) { limit = Infinity; }
    if (!Array.isArray(node))
        node = [node];
    return find(test, node, recurse, limit);
}
exports.filter = filter;
/**
 * Search an array of node and its children for nodes passing a test function.
 *
 * @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`.
 */
function find(test, nodes, recurse, limit) {
    var result = [];
    for (var _i = 0, nodes_1 = nodes; _i < nodes_1.length; _i++) {
        var elem = nodes_1[_i];
        if (test(elem)) {
            result.push(elem);
            if (--limit <= 0)
                break;
        }
        if (recurse && (0, domhandler_1.hasChildren)(elem) && elem.children.length > 0) {
            var children = find(test, elem.children, recurse, limit);
            result.push.apply(result, children);
            limit -= children.length;
            if (limit <= 0)
                break;
        }
    }
    return result;
}
exports.find = find;
/**
 * Finds the first element inside of an array that matches a test function.
 *
 * @param test Function to test nodes on.
 * @param nodes Array of nodes to search.
 * @returns The first node in the array that passes `test`.
 */
function findOneChild(test, nodes) {
    return nodes.find(test);
}
exports.findOneChild = findOneChild;
/**
 * Finds one element in a tree that passes a test.
 *
 * @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`.
 */
function findOne(test, nodes, recurse) {
    if (recurse === void 0) { recurse = true; }
    var elem = null;
    for (var i = 0; i < nodes.length && !elem; i++) {
        var checked = nodes[i];
        if (!(0, domhandler_1.isTag)(checked)) {
            continue;
        }
        else if (test(checked)) {
            elem = checked;
        }
        else if (recurse && checked.children.length > 0) {
            elem = findOne(test, checked.children);
        }
    }
    return elem;
}
exports.findOne = findOne;
/**
 * @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 a test.
 */
function existsOne(test, nodes) {
    return nodes.some(function (checked) {
        return (0, domhandler_1.isTag)(checked) &&
            (test(checked) ||
                (checked.children.length > 0 &&
                    existsOne(test, checked.children)));
    });
}
exports.existsOne = existsOne;
/**
 * Search and array of nodes and its children for nodes passing a test function.
 *
 * Same as `find`, only with less options, leading to reduced complexity.
 *
 * @param test Function to test nodes on.
 * @param nodes Array of nodes to search.
 * @returns All nodes passing `test`.
 */
function findAll(test, nodes) {
    var _a;
    var result = [];
    var stack = nodes.filter(domhandler_1.isTag);
    var elem;
    while ((elem = stack.shift())) {
        var children = (_a = elem.children) === null || _a === void 0 ? void 0 : _a.filter(domhandler_1.isTag);
        if (children && children.length > 0) {
            stack.unshift.apply(stack, children);
        }
        if (test(elem))
            result.push(elem);
    }
    return result;
}
exports.findAll = findAll;