From 47aeff8943bdb0abd654e035952318558c8ea302 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adomas=20Ven=C4=8Dkauskas?= <adomas.ven@gmail.com>
Date: Mon, 28 Sep 2026 10:02:57 +0300
Subject: [PATCH] Do not scroll tree on attachment reparent

---
 chrome/content/zotero/itemTree.jsx       | 20 ++++++-----
 test/tests/collectionViewItemTreeTest.js | 42 +++++++++---------------
 2 files changed, 27 insertions(+), 35 deletions(-)

diff --git a/chrome/content/zotero/itemTree.jsx b/chrome/content/zotero/itemTree.jsx
index 515ceaee17..f24da90f72 100644
--- a/chrome/content/zotero/itemTree.jsx
+++ b/chrome/content/zotero/itemTree.jsx
@@ -1232,7 +1232,7 @@ var ItemTree = class ItemTree extends LibraryTree {
 
 	/**
 	 * Capture selection and scroll position before changing rows. Preserve the first
-	 * visible row by default; single-item edits and reparenting preserve selection scroll.
+	 * visible row by default; single-item edits preserve selection scroll.
 	 * The update's restoreSelection and restoreScroll flags independently apply this state.
 	 *
 	 * @param {Object} [options]
@@ -1360,16 +1360,18 @@ var ItemTree = class ItemTree extends LibraryTree {
 			return;
 		}
 		
-		// Preserve selection scroll for single-item edits and reparenting, including
-		// moves of multiple items. Other bulk changes preserve the first visible row.
-		let preserveSelectionScroll = action == 'modify' && type == 'item'
-			&& (ids.length == 1 || ids.some(id => {
-				let row = this._rowMap[id];
-				if (row === undefined) return false;
+		// Preserve selection scroll for single-item edits (e.g. if a change makes the
+		// item resort and move somewhere else in the tree)
+		// Other changes preserve the first visible row.
+		let preserveSelectionScroll = false;
+		if (action == 'modify' && type == 'item' && ids.length == 1) {
+			let row = this._rowMap[ids[0]];
+			if (row !== undefined) {
 				let parentIndex = this.getParentIndex(row);
 				let oldParentID = parentIndex == -1 ? null : this.getRow(parentIndex).ref.id;
-				return oldParentID != (this.getRow(row).ref.parentItemID || null);
-			}));
+				preserveSelectionScroll = oldParentID == (this.getRow(row).ref.parentItemID || null);
+			}
+		}
 		this._cacheState({ preserveSelectionScroll });
 
 		await this.rowProvider.notify(action, type, ids, extraData);
diff --git a/test/tests/collectionViewItemTreeTest.js b/test/tests/collectionViewItemTreeTest.js
index 8d7e1c9308..95ef347011 100644
--- a/test/tests/collectionViewItemTreeTest.js
+++ b/test/tests/collectionViewItemTreeTest.js
@@ -1210,34 +1210,24 @@ describe("CollectionViewItemTree", function () {
 				assert.equal(treebox.scrollOffset, 0);
 			});
 
-			for (let count of [1, 2]) {
-				it(`should preserve selection scroll position when moving ${count} child item(s) to another parent`, async function () {
-					let attachments = [];
-					for (let i = 0; i < count; i++) {
-						attachments.push(await importFileAttachment('test.png', { parentItemID: items[0].id }));
-					}
-					itemsView.expandAllRows(true);
-					await itemsView.selectItems(attachments.map(item => item.id));
-					treebox.scrollTo(7);
-					let firstSelected = itemsView.getRow(itemsView.getRowIndexByID(items[0].id) + 1).ref;
-					let offset = treebox.getRowPosition(itemsView.getRowIndexByID(firstSelected.id)) - treebox.scrollOffset;
+			it("shouldn't scroll when a selected child item is moved to a parent further down", async function () {
+				let attachment = await importFileAttachment('test.png', { parentItemID: items[0].id });
+				itemsView.expandAllRows(true);
+				await itemsView.selectItem(attachment.id);
+				// Scroll partway into a row, which should be preserved as is
+				treebox.scrollTo(7);
 
-					await Zotero.DB.executeTransaction(async function () {
-						for (let attachment of attachments) {
-							attachment.parentItemID = items[3].id;
-							await attachment.save();
-						}
-					});
-					await itemsView.waitForLoad();
+				attachment.parentItemID = items[3].id;
+				await attachment.saveTx();
+				await itemsView.waitForLoad();
 
-					assert.sameMembers(itemsView.getSelectedItems(true), attachments.map(item => item.id));
-					assert.equal(
-						treebox.getRowPosition(itemsView.getRowIndexByID(firstSelected.id)) - treebox.scrollOffset,
-						offset
-					);
-					assert.isAbove(treebox.scrollOffset, 7);
-				});
-			}
+				assert.sameMembers(itemsView.getSelectedItems(true), [attachment.id]);
+				assert.equal(
+					itemsView.getRowIndexByID(attachment.id),
+					itemsView.getRowIndexByID(items[3].id) + 1
+				);
+				assert.equal(treebox.scrollOffset, 7);
+			});
 		});
 
 		it("should update search results when items are added", async function () {