Fixes a regression in correctly evaluating default param values for functions (#9614)

* Fix: bug in multivalue default params

* Enhance release notes for version 5.4.0

Updated GitHub links and contributors for release notes.

* Add FunctionDefaultValues test for default parameters

* Update function default values in FunctionDefaultValues.tid

* Update #8972.tid

* fix: correctly resolve default values for functions

* Update #8972.tid

core/modules/widgets/widget.js

@@ -160,7 +160,7 @@ Widget.prototype.getVariableInfo = function(name,options) {
 			});
 			// Parameters are an array of {name:, value:, multivalue:} pairs (name and multivalue are optional)
 			$tw.utils.each(params,function(param) {
-				if(param.multiValue) {
+				if(param.multiValue && param.multiValue.length) {
 					variables[param.name] = param.multiValue;
 				} else {
 					variables[param.name] = param.value || "";
@@ -233,8 +233,10 @@ Widget.prototype.resolveVariableParameters = function(formalParams,actualParams)
 			paramMultiValue = typeof param === "string" ? [param] : (param.multiValue || [paramValue]);
 		}
 		// If we've still not got a value, use the default, if any
-		paramValue = paramValue || paramInfo["default"] || "";
-		paramMultiValue = paramMultiValue || [paramValue];
+		if(!paramValue) {
+			paramValue = paramInfo["default"] || "";
+			paramMultiValue = [paramValue];
+		}
 		// Store the parameter name and value
 		results.push({name: paramInfo.name, value: paramValue, multiValue: paramMultiValue});
 	}

editions/test/tiddlers/tests/data/functions/FunctionDefaultValues.tid

@@ -0,0 +1,16 @@
+title: Functions/FunctionDefaultValues
+description: Use defaults for missing parameters in functions in filters
+type: text/vnd.tiddlywiki-multiple
+tags: [[$:/tags/wiki-test-spec]]
+
+title: Output
+
+\whitespace trim
+\function .test(prefix:Default) [[ Content]addprefix<prefix>]
+
+<$text text={{{ [.test[Special]] }}}/>,<$text text={{{ [.test[]] }}}/>
+
++
+title: ExpectedResult
+
+<p>Special Content,Default Content</p>

editions/tw5.com/tiddlers/releasenotes/5.4.0/#8972.tid

@@ -4,8 +4,8 @@ release: 5.4.0
 tags: $:/tags/ChangeNote
 change-type: enhancement
 change-category: hackability
-github-links: https://github.com/TiddlyWiki/TiddlyWiki5/pull/8972
-github-contributors: Jermolene
+github-links: https://github.com/TiddlyWiki/TiddlyWiki5/pull/8972 https://github.com/TiddlyWiki/TiddlyWiki5/pull/9614
+github-contributors: Jermolene saqimtiaz
 
 This PR introduces a new filter run prefix `:let` that assigns the result of the filter run to a variable that is made available for the remaining filter runs of the filter expression. It solves the problem that previously it was impossible to compute values for filter operator parameters; parameters could only be a literal string, text reference or variable reference.