Is it possible to reference the python executable of a different environment in pyproject.toml?

[miccoli]

In most use cases I tend to keep the virtualenv in which mypy is installed distinct from the one in which the code to be tested is installed with its dependencies: e.g from a linting env I would run

mypy --python-executable "$(hatch env find default)/bin/python" 〈module path〉

I was wondering if it is possible to automate this setup in pyproject.toml: i.e. have the command hatch run lint:typing run mypy with the --python-executable pointing to a different virtual environment.

[ofek]

Does this not suffice? https://hatch.pypa.io/latest/config/environment/overview/#detached-environments

[miccoli]

The point is that I would like to be able inside a detached environment to pass a --python-executable argument pointing to the python executable of a different environment.
This is because when you get a “Cannot find implementation or library stub” error you cannot run mypy in a detached environment:

For example, if you are running your code in a virtualenv, make sure to install and use mypy within the virtualenv. Alternatively, if you want to use a globally installed mypy, set the --python-executable command line flag to point the Python interpreter containing your installed third party packages.

An easy fix is to simply install mypy in the default environment, but as said above, I usually prefer to keep the virtualenv in which mypy runs distinct from the virtualenv in which the code is installed.

[ofek]

I see, thank you for the explanation!