Turning on test coverage rebuilds all packages

If I call `stack test --coverage ` in a repository with many packages, all packages (or at least dependencies of "some-package") will be reinstalled with a coverage flag passed to it. This causes a lot of rebuilding (46 packages in my case) and probably generate coverage reports for all of them. In my case, I'm only interested of the coverage of the package I'm testing. Is there a way to tell stack this? If not, would it be possible to add?