diff --git a/src/nodes/code/CodeNode.js b/src/nodes/code/CodeNode.js
index b878972e67c85a..1d731e7f55e9c1 100644
--- a/src/nodes/code/CodeNode.js
+++ b/src/nodes/code/CodeNode.js
@@ -120,6 +120,8 @@ class CodeNode extends Node {
 		data.code = this.code;
 		data.language = this.language;
 
+    	return data;
+
 	}
 
 	deserialize( data ) {
@@ -128,6 +130,9 @@ class CodeNode extends Node {
 
 		this.code = data.code;
 		this.language = data.language;
+		this.includes = data.includes || [];
+
+		return this;
 
 	}
 
diff --git a/src/nodes/code/FunctionNode.js b/src/nodes/code/FunctionNode.js
index d54602064aae0c..87dbe34ee93024 100644
--- a/src/nodes/code/FunctionNode.js
+++ b/src/nodes/code/FunctionNode.js
@@ -105,6 +105,14 @@ class FunctionNode extends CodeNode {
 
 			nodeFunction = builder.parser.parseFunction( this.code );
 
+			if ( ! nodeFunction ) {
+
+				throw new Error(
+					'TSL: Failed to parse function in FunctionNode. Check the shader syntax:\n' + this.code
+				);
+
+			}
+
 			nodeData.nodeFunction = nodeFunction;
 
 		}
@@ -113,6 +121,7 @@ class FunctionNode extends CodeNode {
 
 	}
 
+
 	generate( builder, output ) {
 
 		super.generate( builder );