Musique/node_modules/css-select/lib/sort.js

84 lines
2.4 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var procedure_1 = require("./procedure");
var attributes = {
exists: 10,
equals: 8,
not: 7,
start: 6,
end: 6,
any: 5,
hyphen: 4,
element: 4,
};
/**
* Sort the parts of the passed selector,
* as there is potential for optimization
* (some types of selectors are faster than others)
*
* @param arr Selector to sort
*/
function sortByProcedure(arr) {
var procs = arr.map(getProcedure);
for (var i = 1; i < arr.length; i++) {
var procNew = procs[i];
if (procNew < 0)
continue;
for (var j = i - 1; j >= 0 && procNew < procs[j]; j--) {
var token = arr[j + 1];
arr[j + 1] = arr[j];
arr[j] = token;
procs[j + 1] = procs[j];
procs[j] = procNew;
}
}
}
exports.default = sortByProcedure;
function getProcedure(token) {
var proc = procedure_1.procedure[token.type];
if (token.type === "attribute") {
proc = attributes[token.action];
if (proc === attributes.equals && token.name === "id") {
// Prefer ID selectors (eg. #ID)
proc = 9;
}
if (token.ignoreCase) {
/*
* IgnoreCase adds some overhead, prefer "normal" token
* this is a binary operation, to ensure it's still an int
*/
proc >>= 1;
}
}
else if (token.type === "pseudo") {
if (!token.data) {
proc = 3;
}
else if (token.name === "has" || token.name === "contains") {
proc = 0; // Expensive in any case
}
else if (Array.isArray(token.data)) {
// "matches" and "not"
proc = 0;
for (var i = 0; i < token.data.length; i++) {
// TODO better handling of complex selectors
if (token.data[i].length !== 1)
continue;
var cur = getProcedure(token.data[i][0]);
// Avoid executing :has or :contains
if (cur === 0) {
proc = 0;
break;
}
if (cur > proc)
proc = cur;
}
if (token.data.length > 1 && proc > 0)
proc -= 1;
}
else {
proc = 1;
}
}
return proc;
}