Created attachment 1837 [details]
Example project

The project is structured like this:
  bundle/1/1.txt
  bundle/1/2/2.txt
  source/app.d
  dub.json

dub.json:
{
  "name" : "app",
  "targetPath": "build",
  "copyFiles" : ["bundle/*"]
}

Running DUB should create a `build` folder containing:
  1/1.txt
  1/2/2.txt
  app.exe

Instead, `build` looks like this:
  1/1.txt
  1/2/2.txt
  2/2.txt
  1.txt
  2.txt
  app.exe

I’m using DUB v1.27.0 that ships with DMD v2.098.1.