Asyncify Zotero.Relations.getByObject(), called only from item merge. (#1480)

Use getAsync() to acquire subject in Zotero.Relations.getByObject()

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

@@ -146,7 +146,7 @@ Zotero.Relations = new function () {
 	 * @return {Object[]} - An array of objects with a Zotero.DataObject as 'subject'
 	 *     and a predicate string as 'predicate'
 	 */
-	this.getByObject = function (objectType, object) {
+	this.getByObject = Zotero.Promise.coroutine(function* (objectType, object) {
 		var objectsClass = Zotero.DataObjectUtilities.getObjectsClassForObjectType(objectType);
 		var predicateIDs = [];
 		var o = _subjectPredicatesByObject[objectType]
@@ -156,13 +156,16 @@ Zotero.Relations = new function () {
 		}
 		var toReturn = [];
 		for (let predicateID in o) {
-			o[predicateID].forEach(subjectID => toReturn.push({
+			for (let subjectID of o[predicateID]) {
-				subject: objectsClass.get(subjectID),
+				var subject = yield objectsClass.getAsync(subjectID);
-				predicate: Zotero.RelationPredicates.getName(predicateID)
+				toReturn.push({
-			}));
+					subject: subject,
+					predicate: Zotero.RelationPredicates.getName(predicateID)
+				});
+			};
 		}
 		return toReturn;
-	};
+	});
 	
 	
 	this.updateUser = Zotero.Promise.coroutine(function* (fromUserID, toUserID) {
@@ -179,9 +182,9 @@ Zotero.Relations = new function () {
 			let objects = yield Zotero.DB.columnQueryAsync(
 				sql, 'http://zotero.org/users/' + fromUserID + '/%'
 			);
-			Zotero.DB.addCurrentCallback("commit", function () {
+			Zotero.DB.addCurrentCallback("commit", function* () {
 				for (let object of objects) {
-					let subPrefs = this.getByObject(type, object);
+					let subPrefs = yield this.getByObject(type, object);
 					let newObject = object.replace(
 						new RegExp("^http://zotero.org/users/" + fromUserID + "/(.*)"),
 						"http://zotero.org/users/" + toUserID + "/$1"
@@ -265,4 +268,4 @@ Zotero.Relations = new function () {
 		}
 		throw ("Invalid namespace in URI '" + uri + "' in Zotero.Relations._getPrefixAndValue()");
 	}
-}
+}

test/tests/itemsTest.js

@@ -171,6 +171,55 @@ describe("Zotero.Items", function () {
 			assert.equal(rels[0], item2URI);
 		})
 		
+		it("should merge two items when servant is linked to an item absent from cache", function* () {
+			// two group libraries
+			var groupOneInfo = yield createGroup({
+				id: 25026,
+				name: "Group One"
+			});
+			var libraryOneID = Zotero.Groups.getLibraryIDFromGroupID(groupOneInfo.id);
+
+			var groupTwoInfo = yield createGroup({
+				id: 11592,
+				name: "Group Two"
+			});
+			var libraryTwoID = Zotero.Groups.getLibraryIDFromGroupID(groupTwoInfo.id);
+
+			assert.notEqual(libraryOneID, libraryTwoID);
+
+			// two items in the first library
+			var item1 = yield createDataObject('item', {libraryID: libraryOneID});
+			var item2 = yield createDataObject('item', {libraryID: libraryOneID});
+			var item2URI = Zotero.URI.getItemURI(item2);
+
+			// one item in the second library, linked to item2 as if it dragged and dropped from it
+			var itemX = yield createDataObject('item', {libraryID: libraryTwoID});
+			yield itemX.addLinkedItem(item2);
+
+			// check that the owl:sameAs relation has been registered okay
+			var rels = itemX.getRelationsByPredicate(Zotero.Relations.linkedObjectPredicate);
+			assert.lengthOf(rels, 1);
+			assert.equal(rels[0], item2URI);
+
+			// the freshly minted item is in objectCache, but it might be absent in production,
+			// so we clobber it in this test
+			assert(!!Zotero.Items._objectCache[itemX.id], "itemX is in object cache")
+			delete Zotero.Items._objectCache[itemX.id];
+
+			// merge the two items in the first library
+			yield Zotero.Items.merge(item1, [item2]);
+
+			// check that the merge completed okay
+			assert.isFalse(item1.deleted);
+			assert.isTrue(item2.deleted);
+
+			// Check for merge-tracking relation
+			assert.isFalse(item1.hasChanged());
+			var rels = item1.getRelationsByPredicate(Zotero.Relations.replacedItemPredicate);
+			assert.lengthOf(rels, 1);
+			assert.equal(rels[0], item2URI);
+		})
+
 		it("should move merge-tracking relation from replaced item to master", function* () {
 			var item1 = yield createDataObject('item');
 			var item2 = yield createDataObject('item');