Document exactly what goes into a wheel

[pfmoore]

When building a project using flit-core (the PEP 517 interface, not flit build), I found it quite hard to establish exactly what gets included in the generated wheel. I was getting some unexpected .pyd files included, which it turns out were hidden by my .gitignore file, but flit includes them anyway. On the other hand, all of the __pycache__ directories in my working project are excluded from the wheel. So clearly flit has some logic for what gets included, but I couldn't find it documented anywhere.

If I've missed a note in the docs, I'm sorry. I was hoping for something at the top level, and while I did look through the rest of the docs, even if I did miss something, maybe it could be "promoted" to a section in its own right?

[takluyver]

Thanks, I agree this should be more clearly documented. There's a brief note in the docs about controlling what goes into an sdist:

everything it needs to build and install your module: the package contents (including non-Python data files, but not .pyc bytecode files)...

If you have a package folder, everything inside that is included by default, on the assumption that it's package data, with the specific exception of Python bytecode files.

The logic for this is here:

flit/flit_core/flit_core/common.py

Lines 95 to 107 in 13792b5

	def _include(path):
	name = os.path.basename(path)
	return name != '__pycache__' and not name.endswith('.pyc')
	if self.is_package:
	# Ensure we sort all files and directories so the order is stable
	for dirpath, dirs, files in os.walk(str(self.path)):
	for file in sorted(files):
	full_path = os.path.join(dirpath, file)
	if _include(full_path):
	yield full_path
	dirs[:] = [d for d in sorted(dirs) if _include(d)]

[pfmoore]

If you have a package folder, everything inside that is included by default

That's what I assumed (and it's a bit short to warrant a headline section in the docs 🙂) but it would still be nice to have it noted somewhere.

Maybe changing the "sdist section" section to be "Content of distribution files" would work? It's a bit awkward as it sits under "The pyproject.toml config file" but it would have been suitable for me when I was looking for the information. If you think this is reasonable, I can create a PR.

[pfmoore]

I've created a PR with the suggested change as #748