commit

node_modules/css-select/lib/sort.js

@@ -0,0 +1,85 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+var css_what_1 = require("css-what");
+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 === css_what_1.SelectorType.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 === css_what_1.SelectorType.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;
+}