Support creating stub-only packages

• I have searched the issues of this repo and believe that this is not a duplicate.

Issue

MyPy documentation explains how to create stub-only packages. It would be nice if Poetry supported stub-only packages. Current behaviour:

$ fd
ordered_set-stubs
pyproject.toml
LICENSE
README.md
ordered_set-stubs/__init__.pyi
$ poetry build
Skipping virtualenv creation, as specified in config file.
Building ordered_set-stubs (0.1.0)
                                                      
[ValueError]                           
No file/folder found for package ordered-set-stubs  
                                                      
build [-f|--format FORMAT]

[fsenart]

@sdispater right after version 1.0.0, in version 1.0.1, stub-only packages are no longer supported. One gets an ... is not a package. error. @rominf this issue should be reopened.

[sdispater]

It’s already supported. Just add the following to the [tool.poetry] section.

[tool.poetry]
# Basic package information

packages = [
    {include = "ordered_set-stubs"}
]

Then, if you run poetry build you should have stub-only distributions.