WebUI: filter array elements in-place

Currently JS `Array` have no method to filter element in-place so we provide one which result
in better performance and less memory allocations.

Author: Chocobo1

src/webui/www/private/rename_files.html

@@ -254,9 +254,11 @@
                 document.getElementById("renameOptions").disabled = false;
 
                 // Recreate table
-                let selectedRows = bulkRenameFilesTable.getSelectedRows().map(row => row.rowId.toString());
-                for (const renamedRow of rows)
-                    selectedRows = selectedRows.filter(selectedRow => selectedRow !== renamedRow.rowId.toString());
+                const selectedRows = bulkRenameFilesTable.getSelectedRows().map(row => row.rowId.toString());
+                for (const renamedRow of rows) {
+                    const id = renamedRow.rowId.toString();
+                    window.qBittorrent.Misc.filterInPlace(selectedRows, (row => row !== id));
+                }
                 bulkRenameFilesTable.clear();
 
                 // Adjust file enumeration count by 1 when replacing single files to prevent naming conflicts

src/webui/www/private/scripts/dynamicTable.js

@@ -871,13 +871,7 @@ window.qBittorrent.DynamicTable ??= (() => {
 
         updateTable(fullUpdate = false) {
             const rows = this.getFilteredAndSortedRows();
-
-            for (let i = 0; i < this.selectedRows.length; ++i) {
-                if (!(this.selectedRows[i] in rows)) {
-                    this.selectedRows.splice(i, 1);
-                    --i;
-                }
-            }
+            window.qBittorrent.Misc.filterInPlace(this.selectedRows, (selectedRow => selectedRow in rows));
 
             if (this.useVirtualList) {
                 // rerender on table update
@@ -2832,7 +2826,8 @@ window.qBittorrent.DynamicTable ??= (() => {
 
         getSelectedRows() {
             const nodes = this.fileTree.toArray();
-            return nodes.filter(x => x.checked === 0);
+            window.qBittorrent.Misc.filterInPlace(nodes, (node => node.checked === 0));
+            return nodes;
         }
 
         initColumns() {

src/webui/www/private/scripts/misc.js

@@ -34,6 +34,7 @@ window.qBittorrent.Misc ??= (() => {
         return {
             getHost: getHost,
             createDebounceHandler: createDebounceHandler,
+            filterInPlace: filterInPlace,
             friendlyUnit: friendlyUnit,
             friendlyDuration: friendlyDuration,
             friendlyPercentage: friendlyPercentage,
@@ -90,6 +91,18 @@ window.qBittorrent.Misc ??= (() => {
         };
     };
 
+    const filterInPlace = (array, predicate) => {
+        let j = 0;
+        for (let i = 0; i < array.length; ++i) {
+            if (predicate(array[i])) {
+                if (i > j)
+                    array[j] = array[i];
+                ++j;
+            }
+        }
+        array.splice(j, (array.length - j));
+    };
+
     /*
      * JS counterpart of the function in src/misc.cpp
      */

src/webui/www/private/views/rss.html

@@ -275,7 +275,7 @@
                             .map((rowID) => rssFeedTable.getRow(rowID).full_data.dataPath);
                         // filter children
                         const reducedDatapaths = selectedDatapaths.filter((path) =>
-                            selectedDatapaths.filter((innerPath) => path.slice(0, innerPath.length) === innerPath).length === 1
+                            selectedDatapaths.filter(path.startsWith).length === 1
                         );
                         removeItem(reducedDatapaths);
                     },
@@ -428,7 +428,7 @@
                     childFeeds.add(row.full_data.dataUid);
             }
 
-            let visibleArticles = [];
+            const visibleArticles = [];
             for (const feedEntry in feedData) {
                 if (childFeeds.has(feedEntry)) {
                     visibleArticles.append(feedData[feedEntry]
@@ -440,12 +440,12 @@
             }
             // filter read articles if "Unread" feed is selected
             if (path === "")
-                visibleArticles = visibleArticles.filter((a) => !a.isRead);
+                window.qBittorrent.Misc.filterInPlace(visibleArticles, (article => !article.isRead));
 
             const rssFilterInput = document.getElementById("rssFilterInput");
             if (rssFilterInput.value.length > 0) {
                 const lowerFilter = rssFilterInput.value.toLowerCase();
-                visibleArticles = visibleArticles.filter((a) => a.title.toLowerCase().includes(lowerFilter));
+                window.qBittorrent.Misc.filterInPlace(visibleArticles, (article => article.title.toLowerCase().includes(lowerFilter)));
             }
 
             let rowID = -1;

src/webui/www/test/private/misc.test.js

@@ -30,6 +30,19 @@ import { expect, test, vi } from "vitest";
 
 import "../../private/scripts/misc.js";
 
+test("Test filterInPlace()", () => {
+    const filterInPlace = (array, predicate) => {
+        window.qBittorrent.Misc.filterInPlace(array, predicate);
+        return array;
+    };
+
+    expect(filterInPlace([], (() => true))).toStrictEqual([]);
+    expect(filterInPlace([], (() => false))).toStrictEqual([]);
+    expect(filterInPlace([1, 2, 3, 4], (() => true))).toStrictEqual([1, 2, 3, 4]);
+    expect(filterInPlace([1, 2, 3, 4], (() => false))).toStrictEqual([]);
+    expect(filterInPlace([1, 2, 3, 4], (x) => { return (x % 2) === 0; })).toStrictEqual([2, 4]);
+});
+
 test("Test toFixedPointString()", () => {
     const toFixedPointString = window.qBittorrent.Misc.toFixedPointString;