``` black @ git+https://github.com/psf/black ```

We also support editable installs for local directories, like you mentioned:

``` black @ ../black ```

The thing we don't support is using _editable_ installs for Git and direct URL dependencies, like:

``` -e git+https://github.com/psf/black ```

In my experience, these are really rare, and we didn't see a reason to support them.