GitLab

tools/manifestfile.py: Add support for publishing packages to PyPI.

This adds a new MODE_PYPROJECT, which gives basic support to allow
packaging a small subset of micropython-lib packages to PyPI.

This change allows a package in micropython-lib to:
- Add a "pypi" name to its metadata indicating that it's based on a PyPI
  package.
- Add "stdlib" to its metadata indicating that it's a micropython version
  of a stdlib package.
- Add a "pypi_publish" name to its metadata to indicate that it can be
  published to PyPI (this can be different to the package name, e.g. "foo"
  might want to be published as "micropython-foo").

When a package requires() another one, if it's in MODE_PYPROJECT then if
the package is from pypi then it will record that as a pypi dependency
instead (or no dependency at all if it's from stdlib).

Also allows require() to explicitly specify the pypi name.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>