Fix sync errors from remote item referencing deleted local collection

chrome/content/zotero/bindings/merge.xml

@@ -380,10 +380,15 @@
 					// Store JSON
 					this._data = val;
 					
+					// Create a copy of the JSON that we can clean for display, since the remote object
+					// might reference things that don't exist locally
+					var displayJSON = Object.assign({}, val);
+					displayJSON.collections = [];
+					
 					// Create item from JSON for metadata box
 					var item = new Zotero.Item(val.itemType);
 					item.libraryID = this.libraryID;
-					item.fromJSON(val);
+					item.fromJSON(displayJSON);
 					objbox.item = item;
 				]]>
 				</setter>

chrome/content/zotero/xpcom/data/item.js

@@ -3505,7 +3505,7 @@ Zotero.Item.prototype.setCollections = function (collectionIDsOrKeys) {
 		var id = this.ContainerObjectsClass.getIDFromLibraryAndKey(this.libraryID, val);
 		if (!id) {
 			let e = new Error("Collection " + val + " not found for item " + this.libraryKey);
-			e.name = "ZoteroObjectNotFoundError";
+			e.name = "ZoteroMissingObjectError";
 			throw e;
 		}
 		return id;

chrome/content/zotero/xpcom/sync/syncEngine.js

@@ -694,9 +694,9 @@ Zotero.Sync.Data.Engine.prototype._downloadObjects = async function (objectType,
 		let results = await Zotero.Sync.Data.Local.processConflicts(
 			objectType, this.libraryID, conflicts, this._getOptions()
 		);
-		// Keys can be unprocessed if conflict resolution is cancelled
 		let keys = results.filter(x => x.processed).map(x => x.key);
-		if (!keys.length) {
+		// If all keys are unprocessed and didn't fail from an error, conflict resolution was cancelled
+		if (results.every(x => !x.processed && !x.error)) {
 			throw new Zotero.Sync.UserCancelledException();
 		}
 		await Zotero.Sync.Data.Local.removeObjectsFromSyncQueue(objectType, this.libraryID, keys);

chrome/content/zotero/xpcom/sync/syncExceptions.js

@@ -30,7 +30,7 @@
  *     sync completely
  */
 Zotero.Sync.UserCancelledException = function (advanceToNextLibrary) {
-	this.message = "Sync cancelled";
+	this.message = "User cancelled sync";
 	this.advanceToNextLibrary = advanceToNextLibrary;
 }
 

test/tests/syncEngineTest.js

@@ -2102,6 +2102,130 @@ describe("Zotero.Sync.Data.Engine", function () {
 			assert.isTrue(Zotero.Items.exists(itemID2));
 		})
 		
+		
+		it("should handle new remote item referencing locally deleted collection", async function () {
+			var lastLibraryVersion = 5;
+			var newLibraryVersion = 6;
+			var library = Zotero.Libraries.userLibrary;
+			library.libraryVersion = lastLibraryVersion;
+			await library.saveTx();
+			({ engine, client, caller } = await setup({
+				stopOnError: false
+			}));
+			
+			// Create local deleted collection
+			var collection = await createDataObject('collection');
+			var collectionKey = collection.key;
+			await collection.eraseTx();
+			// Create item JSON
+			var item = await createDataObject('item');
+			var itemResponseJSON = item.toResponseJSON();
+			// Add collection to remote item
+			itemResponseJSON.data.collections = [collectionKey];
+			var itemKey = item.key;
+			await item.eraseTx({
+				skipDeleteLog: true
+			});
+			
+			var headers = {
+				"Last-Modified-Version": newLibraryVersion
+			};
+			setDefaultResponses({
+				lastLibraryVersion,
+				libraryVersion: newLibraryVersion
+			});
+			setResponse({
+				method: "GET",
+				url: `users/1/items?format=versions&since=${lastLibraryVersion}&includeTrashed=1`,
+				status: 200,
+				headers,
+				json: {
+					[itemKey]: newLibraryVersion
+				}
+			});
+			setResponse({
+				method: "GET",
+				url: `users/1/items?format=json&itemKey=${itemKey}&includeTrashed=1`,
+				status: 200,
+				headers,
+				json: [itemResponseJSON]
+			});
+			
+			await engine._startDownload();
+			
+			// Item should be skipped and added to queue, which will allow collection deletion to upload
+			var keys = await Zotero.Sync.Data.Local.getObjectsFromSyncQueue('item', library.id);
+			assert.sameMembers(keys, [itemKey]);
+		});
+		
+		
+		it("should handle conflict with remote item referencing deleted local collection", async function () {
+			var lastLibraryVersion = 5;
+			var newLibraryVersion = 6;
+			var library = Zotero.Libraries.userLibrary;
+			library.libraryVersion = lastLibraryVersion;
+			await library.saveTx();
+			({ engine, client, caller } = await setup({
+				stopOnError: false
+			}));
+			
+			// Create local deleted collection and item
+			var collection = await createDataObject('collection');
+			var collectionKey = collection.key;
+			await collection.eraseTx();
+			var item = await createDataObject('item');
+			var itemResponseJSON = item.toResponseJSON();
+			// Add collection to remote item
+			itemResponseJSON.data.collections = [collectionKey];
+			var itemKey = item.key;
+			await item.eraseTx();
+			
+			var headers = {
+				"Last-Modified-Version": newLibraryVersion
+			};
+			setDefaultResponses({
+				lastLibraryVersion,
+				libraryVersion: newLibraryVersion
+			});
+			setResponse({
+				method: "GET",
+				url: `users/1/items?format=versions&since=${lastLibraryVersion}&includeTrashed=1`,
+				status: 200,
+				headers,
+				json: {
+					[itemKey]: newLibraryVersion
+				}
+			});
+			setResponse({
+				method: "GET",
+				url: `users/1/items?format=json&itemKey=${itemKey}&includeTrashed=1`,
+				status: 200,
+				headers,
+				json: [itemResponseJSON]
+			});
+			
+			// This will trigger a conflict for a remote item that references a collection that doesn't
+			// exist. The collection should be removed for display in the CR window, and then the save
+			// should fail and the item should be added to the queue so that the collection deletion
+			// can upload.
+			waitForWindow('chrome://zotero/content/merge.xul', function (dialog) {
+				var doc = dialog.document;
+				var wizard = doc.documentElement;
+				var mergeGroup = wizard.getElementsByTagName('zoteromergegroup')[0];
+				
+				// 1 (accept remote)
+				//assert.equal(mergeGroup.leftpane.getAttribute('selected'), 'true');
+				mergeGroup.rightpane.click();
+				wizard.getButton('finish').click();
+			});
+			await engine._startDownload();
+			
+			// Item should be skipped and added to queue, which will allow collection deletion to upload
+			var keys = await Zotero.Sync.Data.Local.getObjectsFromSyncQueue('item', library.id);
+			assert.sameMembers(keys, [itemKey]);
+		});
+		
+		
 		it("should handle cancellation of conflict resolution window", function* () {
 			var library = Zotero.Libraries.userLibrary;
 			library.libraryVersion = 5;