Program: 124494
Project: 124494
Buggy source:
public Canvas<Element> render(final VisualTextField<Object> visualTextField){
  Canvas<Element> canvas=ServiceLocator.getInstance().getTemplateManager().getCanvasFactory().createCanvas();
  canvas.setContent(new MergeableElement(){
    public void mergeWith(    final Element textFieldElement){
      final String id=DragomeEntityManager.add(visualTextField);
      visualTextField.addValueChangeHandler(new ValueChangeHandler<Object>(){
        public void onValueChange(        ValueChangeEvent<Object> event){
          String value=(String)event.getValue();
          textFieldElement.setAttribute("String_Node_Str",value);
          ScriptHelper.put("String_Node_Str",textFieldElement,this);
          ScriptHelper.put("String_Node_Str",value,this);
          ScriptHelper.evalNoResult("String_Node_Str",this);
        }
      }
);
      visualTextField.addListener(InputListener.class,new InputListener(){
        public void inputPerformed(        VisualComponent visualComponent){
          ScriptHelper.put("String_Node_Str",textFieldElement,this);
          String value=(String)ScriptHelper.eval("String_Node_Str",this);
          visualTextField.setValue(value);
        }
      }
);
      visualTextField.addListener(FocusListener.class,new FocusListener(){
        public void focusGained(        VisualComponent component){
          ScriptHelper.put("String_Node_Str",textFieldElement,this);
          ScriptHelper.evalNoResult("String_Node_Str",this);
        }
        public void focusLost(        VisualComponent component){
        }
      }
);
      String value=visualTextField.getRenderer().render(visualTextField.getValue());
      textFieldElement.setAttribute("String_Node_Str","String_Node_Str");
      textFieldElement.setAttribute("String_Node_Str",value);
      textFieldElement.setAttribute(COMPONENT_ID_ATTRIBUTE,id);
      ScriptHelper.put("String_Node_Str",value == null ? "String_Node_Str" : value,this);
      ScriptHelper.put("String_Node_Str",textFieldElement,this);
      ScriptHelper.evalNoResult("String_Node_Str",this);
      addListeners(visualTextField,textFieldElement);
    }
  }
);
  return canvas;
}

Fixed version (ground truth):
public Canvas<Element> render(final VisualTextField<Object> visualTextField){
  Canvas<Element> canvas=ServiceLocator.getInstance().getTemplateManager().getCanvasFactory().createCanvas();
  canvas.setContent(new MergeableElement(){
    public void mergeWith(    final Element textFieldElement){
      final String id=DragomeEntityManager.add(visualTextField);
      visualTextField.addValueChangeHandler(new ValueChangeHandler<Object>(){
        public void onValueChange(        ValueChangeEvent<Object> event){
          String value=visualTextField.getRenderer().render(event.getValue());
          textFieldElement.setAttribute("String_Node_Str",value);
          ScriptHelper.put("String_Node_Str",textFieldElement,this);
          ScriptHelper.put("String_Node_Str",value,this);
          ScriptHelper.evalNoResult("String_Node_Str",this);
        }
      }
);
      visualTextField.addListener(InputListener.class,new InputListener(){
        public void inputPerformed(        VisualComponent visualComponent){
          ScriptHelper.put("String_Node_Str",textFieldElement,this);
          String value=(String)ScriptHelper.eval("String_Node_Str",this);
          visualTextField.setValue(value);
        }
      }
);
      visualTextField.addListener(FocusListener.class,new FocusListener(){
        public void focusGained(        VisualComponent component){
          ScriptHelper.put("String_Node_Str",textFieldElement,this);
          ScriptHelper.evalNoResult("String_Node_Str",this);
        }
        public void focusLost(        VisualComponent component){
        }
      }
);
      String value=visualTextField.getRenderer().render(visualTextField.getValue());
      textFieldElement.setAttribute("String_Node_Str","String_Node_Str");
      textFieldElement.setAttribute("String_Node_Str",value);
      textFieldElement.setAttribute(COMPONENT_ID_ATTRIBUTE,id);
      ScriptHelper.put("String_Node_Str",value == null ? "String_Node_Str" : value,this);
      ScriptHelper.put("String_Node_Str",textFieldElement,this);
      ScriptHelper.evalNoResult("String_Node_Str",this);
      addListeners(visualTextField,textFieldElement);
    }
  }
);
  return canvas;
}