Fix delaying if remote library version changes during downloads

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

@@ -154,7 +154,7 @@ Zotero.Sync.Data.Engine.prototype.start = Zotero.Promise.coroutine(function* ()
 			
 			if (!gen) {
 				var gen = Zotero.Utilities.Internal.delayGenerator(
-					Zotero.Sync.Data.delayIntervals, 60 * 1000
+					Zotero.Sync.Data.conflictDelayIntervals, 60 * 1000
 				);
 			}
 			// After the first upload version conflict (which is expected after remote changes),
@@ -211,7 +211,7 @@ Zotero.Sync.Data.Engine.prototype._startDownload = Zotero.Promise.coroutine(func
 	var newLibraryVersion;
 	
 	this.downloadDelayGenerator = Zotero.Utilities.Internal.delayGenerator(
-		Zotero.Sync.Data.delayIntervals, 60 * 60 * 1000
+		Zotero.Sync.Data.conflictDelayIntervals, 60 * 60 * 1000
 	);
 	
 	loop:
@@ -740,7 +740,7 @@ Zotero.Sync.Data.Engine.prototype._downloadDeletions = Zotero.Promise.coroutine(
  */
 Zotero.Sync.Data.Engine.prototype._onLibraryVersionChange = Zotero.Promise.coroutine(function* (mode) {
 	Zotero.logError("Library version changed since last download -- restarting sync");
-	let keepGoing = yield this.downloadDelayGenerator.next();
+	let keepGoing = yield this.downloadDelayGenerator.next().value;
 	if (!keepGoing) {
 		throw new Error("Could not update " + this.library.name + " -- library in use");
 	}

test/tests/syncEngineTest.js

@@ -1905,6 +1905,68 @@ describe("Zotero.Sync.Data.Engine", function () {
 			// Library version should not have advanced
 			assert.equal(library.libraryVersion, 5);
 		});
+		
+		it("should restart if remote library version changes", function* () {
+			var library = Zotero.Libraries.userLibrary;
+			library.libraryVersion = 5;
+			yield library.saveTx();
+			({ engine, client, caller } = yield setup());
+			
+			var lastLibraryVersion = 5;
+			var calls = 0;
+			var t;
+			server.respond(function (req) {
+				if (req.url.startsWith(baseURL + "users/1/settings")) {
+					calls++;
+					if (calls == 2) {
+						assert.isAbove(new Date() - t, 50);
+					}
+					t = new Date();
+					req.respond(
+						200,
+						{
+							"Last-Modified-Version": ++lastLibraryVersion
+						},
+						JSON.stringify({})
+					);
+					return;
+				}
+				else if (req.url.startsWith(baseURL + "users/1/searches")) {
+					if (calls == 1) {
+						t = new Date();
+						req.respond(
+							200,
+							{
+								// On the first pass, return a later library version to simulate data
+								// being updated by a concurrent upload
+								"Last-Modified-Version": lastLibraryVersion + 1
+							},
+							JSON.stringify([])
+						);
+						return;
+					}
+				}
+				else if (req.url.startsWith(baseURL + "users/1/items")) {
+					// Since /searches is called before /items and it should cause a reset,
+					// /items shouldn't be called until the second pass
+					if (calls < 1) {
+						throw new Error("/users/1/items called in first pass");
+					}
+				}
+				
+				t = new Date();
+				req.respond(
+					200,
+					{
+						"Last-Modified-Version": lastLibraryVersion
+					},
+					JSON.stringify([])
+				);
+			});
+			
+			Zotero.Sync.Data.conflictDelayIntervals = [50, 70000];
+			yield engine._startDownload();
+		});
 	});