diff options
Diffstat (limited to 'node_modules/css-select/lib/sort.js')
-rw-r--r-- | node_modules/css-select/lib/sort.js | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/node_modules/css-select/lib/sort.js b/node_modules/css-select/lib/sort.js new file mode 100644 index 0000000..ae01830 --- /dev/null +++ b/node_modules/css-select/lib/sort.js @@ -0,0 +1,84 @@ +"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; +} |