Fixes feed sync bugs after conflicts. (#1074)

SyncedSettings.set() caches values. If an object passed to set() is
modified after the call then get() returns that modified object.

chrome/content/zotero/xpcom/syncedSettings.js

@@ -177,6 +177,14 @@ Zotero.SyncedSettings = (function () {
 				throw new Error("Value not provided");
 			}
 			
+			// Prevents a whole bunch of headache if you continue modifying the object after calling #set()
+			if (value instanceof Array) {
+				value = Array.from(value);
+			}
+			else if (typeof value == 'object') {
+				value = Object.assign({}, value);
+			}
+			
 			var currentValue = this.get(libraryID, setting);
 			var hasCurrentValue = currentValue !== null;
 			

chrome/content/zotero/xpcom/zotero.js

@@ -643,9 +643,11 @@ Components.utils.import("resource://gre/modules/osfile.jsm");
 				yield Zotero.Promise.each(
 					Zotero.Libraries.getAll(),
 					library => Zotero.Promise.coroutine(function* () {
-						yield Zotero.SyncedSettings.loadAll(library.libraryID);
-						yield Zotero.Collections.loadAll(library.libraryID);
-						yield Zotero.Searches.loadAll(library.libraryID);
+						if (library.libraryType != 'feed') {
+							yield Zotero.SyncedSettings.loadAll(library.libraryID);
+							yield Zotero.Collections.loadAll(library.libraryID);
+							yield Zotero.Searches.loadAll(library.libraryID);
+						}
 					})()
 				);
 			}

test/tests/syncedSettingsTest.js

@@ -0,0 +1,10 @@
+describe('Zotero.SyncedSettings', function() {
+	it('should not affect cached value when modifying the setting after #set() call', function* () {
+		let setting = {athing: 1};
+		yield Zotero.SyncedSettings.set(Zotero.Libraries.userLibraryID, 'setting', setting);
+		
+		setting.athing = 2;
+		let storedSetting = Zotero.SyncedSettings.get(Zotero.Libraries.userLibraryID, 'setting');
+		assert.notDeepEqual(setting, storedSetting);
+	});
+});