Running mypy on doctests

Hi!

I am trying to make a custom tool to run mypy on doctests inside my project.
Because I want to be sure that my examples are correct. And since pytest / doctest modules do it with ease I am seeking the similar solution but for types. Examples, where I need this:

• https://github.com/dry-python/classes/blob/master/docs/pages/concept.rst
• https://github.com/dry-python/returns/blob/master/returns/result.py#L135

So, I have started with using api. It works fine, but requires to create temp files with extracted doctest code contents. This is a working solution, but the only ugly part is that it is based on temporary files. And reports incorrect filenames, locations, etc.

I have tried to go deeper and pass just the source code / ast parts. But, it does not look like it works this way. Is there a way to make it work without touching a lot of protected / private APIs?

Maybe this can be implemented in mypy itself at sometime?

Thanks!

Beginne mit mypy/api.py und überprüfe, wie dessen öffentliche API Quelltext akzeptiert und Dateinamen sowie Positionen meldet. Vergleiche dieses Verhalten mit dem im Issue beschriebenen Ansatz mit temporären Dateien; die Arbeit ist abgeschlossen, wenn doctest-Code ohne temporäre Dateien geprüft werden kann und dabei genaue Dateinamen und Positionen erhalten bleiben.