Warning processing copy-to with preprocess step

[jlacour31]

Given the following ditamap:

<map>
    <title>Map</title>
    <topicref href="topic.dita" copy-to="topic_dir.dita"/>
</map>

When I run any transformation using preprocess I get:
==> Debug and filter input files
Warning: Ignoring a copy-to file file:/.../topic_dir.dita

Using preprocess2 I don't have the situation.

[jelovirt]

Not sure about this, but I think preprocess skips a copy-to that is not necessarily needed, but preprocess2 respects the source and processes the copy-to.

[jlacour31]

The thing is I did get the copy-to file in the output dir, in my use-case "topic_dir.html" and the link from index.html did open the copied file.
From my scenario, the copy-to is not necessary as I don't need two copies of my topic but I was expecting either to get the warning and no copied HTML file or no warning and the copied HTML file.