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- import { AttributeAction, SelectorType, isTraversal as isTraversalBase, } from "css-what";
- export function isTraversal(token) {
- return token.type === "_flexibleDescendant" || isTraversalBase(token);
- }
- /**
- * 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
- */
- export function sortRules(arr) {
- const ratings = arr.map(getQuality);
- for (let i = 1; i < arr.length; i++) {
- const procNew = ratings[i];
- if (procNew < 0)
- continue;
- // Use insertion sort to move the token to the correct position.
- for (let j = i; j > 0 && procNew < ratings[j - 1]; j--) {
- const token = arr[j];
- arr[j] = arr[j - 1];
- arr[j - 1] = token;
- ratings[j] = ratings[j - 1];
- ratings[j - 1] = procNew;
- }
- }
- }
- function getAttributeQuality(token) {
- switch (token.action) {
- case AttributeAction.Exists: {
- return 10;
- }
- case AttributeAction.Equals: {
- // Prefer ID selectors (eg. #ID)
- return token.name === "id" ? 9 : 8;
- }
- case AttributeAction.Not: {
- return 7;
- }
- case AttributeAction.Start: {
- return 6;
- }
- case AttributeAction.End: {
- return 6;
- }
- case AttributeAction.Any: {
- return 5;
- }
- case AttributeAction.Hyphen: {
- return 4;
- }
- case AttributeAction.Element: {
- return 3;
- }
- }
- }
- /**
- * Determine the quality of the passed token. The higher the number, the
- * faster the token is to execute.
- *
- * @param token Token to get the quality of.
- * @returns The token's quality.
- */
- export function getQuality(token) {
- // eslint-disable-next-line @typescript-eslint/switch-exhaustiveness-check
- switch (token.type) {
- case SelectorType.Universal: {
- return 50;
- }
- case SelectorType.Tag: {
- return 30;
- }
- case SelectorType.Attribute: {
- return Math.floor(getAttributeQuality(token) /
- // `ignoreCase` adds some overhead, half the result if applicable.
- (token.ignoreCase ? 2 : 1));
- }
- case SelectorType.Pseudo: {
- return !token.data
- ? 3
- : token.name === "has" ||
- token.name === "contains" ||
- token.name === "icontains"
- ? // Expensive in any case — run as late as possible.
- 0
- : Array.isArray(token.data)
- ? // Eg. `:is`, `:not`
- Math.max(
- // If we have traversals, try to avoid executing this selector
- 0, Math.min(...token.data.map((d) => Math.min(...d.map(getQuality)))))
- : 2;
- }
- default: {
- return -1;
- }
- }
- }
- export function includesScopePseudo(t) {
- return (t.type === SelectorType.Pseudo &&
- (t.name === "scope" ||
- (Array.isArray(t.data) &&
- t.data.some((data) => data.some(includesScopePseudo)))));
- }
- //# sourceMappingURL=selectors.js.map
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