Add Zotero.Utilities.processAsync(sets, callbacks, onDone) -- this can be used from translators to make it easier to correctly chain sets of asynchronous callbacks, since most translators that require multiple callbacks currently do it incorrectly.

This function definition will be automatically prepended to translators sent to older clients from the repo.

chrome/content/zotero/xpcom/utilities.js

@@ -535,6 +535,42 @@ Zotero.Utilities.prototype.capitalizeTitle = function(string, force) {
 	return string;
 }
 
+
+/**
+ * Run sets of data through multiple asynchronous callbacks
+ *
+ * Each callback is passed the current set and a callback to call when done
+ *
+ * @param	{Object[]}		sets			Sets of data
+ * @param	{Function[]}	callbacks
+ * @param	{Function}		onDone			Function to call when done
+ */
+Zotero.Utilities.prototype.processAsync = function (sets, callbacks, onDone) {
+	var currentSet;
+	var index = 0;
+	
+	var nextSet = function () {
+		if (!sets.length) {
+			onDone();
+			return;
+		}
+		index = 0;
+		currentSet = sets.shift();
+		callbacks[0](currentSet, nextCallback);
+	};
+	var nextCallback = function () {
+		callbacks[index](currentSet, nextCallback);
+		index++;
+	};
+	
+	// Add a final callback to proceed to the next set
+	callbacks[callbacks.length] = function () {
+		nextSet();
+	}
+	nextSet();
+}
+
+
 /**
  * @class All functions accessible from within Zotero.Utilities namespace inside sandboxed
  * translators
@@ -666,6 +702,7 @@ Zotero.Utilities.Translate.prototype.getItemArray = function(doc, inHere, urlRe,
 	return availableItems;
 }
 
+
 /**
  * Load a single document in a hidden browser
  *