Do not leave action implementation blank

Let's look at the action edit in a controller.

def edit
end

In the above method, it is not clear whether that method's implementation is complete or not, since developers sometimes forget to complete the method.

Here is a way to remove that ambiguity.

If the implementation is complete, then just add the word render.

def edit
  render
end

Now, when one looks at the method, it's clear that the developer did not forget anything. The developer is explicitly saying that the only thing this method does is render the view.