Fix tests

core/modules/filterrunprefixes/let.js

@@ -16,6 +16,7 @@ Assign a value to a variable
 Export our filter prefix function
 */
 exports.let = function(operationSubFunction,options) {
+	if(options.suffixes[0] && options.suffixes[0][0]) {
 		// Save the variable name
 		var name = options.suffixes[0][0];
 		// Return the filter run prefix function
@@ -32,6 +33,12 @@ exports.let = function(operationSubFunction,options) {
 				variables: variables
 			};
 		};
+	} else {
+		// Return nothing if there is no variable name
+		return function(results,source,widget) {
+		};
+
+	}
 };
 
 })();

editions/test/tiddlers/tests/data/let-filter-prefix/UseInput.tid

@@ -5,7 +5,7 @@ tags: [[$:/tags/wiki-test-spec]]
 
 title: Output
 
-<$text text={{{ [[colossus]] :let:another[addprefix[something]] [<another>] +[join[-]] }}}/>
+<$text text={{{ [[colossus]] :let:another[all[]] [<another>] +[join[-]] }}}/>
 +
 title: ExpectedResult