TSL: Fix expected output if used a.assign( b ), returns a

Author: sunag

examples/jsm/nodes/shadernode/ShaderNode.js

@@ -40,7 +40,13 @@ const shaderNodeHandler = {
 
 			if ( node.isStackNode !== true && prop === 'assign' ) {
 
-				return ( ...params ) => currentStack.assign( nodeObj, ...params );
+				return ( ...params ) => {
+
+					currentStack.assign( nodeObj, ...params );
+
+					return nodeObj;
+
+				};
 
 			} else if ( NodeElements.has( prop ) ) {