Today I created a setup.py-file and found one working script and two none working scenarios.
In the two non working scenarios the package_data after is missing in the build. I created the build with python setup.py sdist.
Why scenario 2 and 3 don't include my package data?
Scenario 1 works:
import os 
from distutils.core import setup
def find_packages(path):
    package_path = os.path.join(os.path.dirname(__file__), path)
    packages = []
    for f in os.walk(package_path):
    directory_name = f[0]
    if directory_name.endswith('egg-info') or directory_name.endswith('path'):
        continue
    directory_name = directory_name.replace(package_path, '').replace('/', '.').strip()
    if not len(directory_name):
        continue
    if directory_name.startswith('.'):
        directory_name = directory_name.replace('.', '', 1)
    packages.append(directory_name)
return packages
setup (
    name = 'mypkg',
    packages = find_packages('src'),
    package_dir = {'mypkg': 'src/mypkg'},
    include_package_data = True,
    package_data = {
        '': ['*.txt'],
        'mypkg': ['data/*.dat'],
    }
)
Scenario 2, doesn't work:
from setuptools import setup #, find_packages
from setuptools.command import sdist
setup (
    name = 'mypkg',
    packages = ['mypkg'],
    package_dir = {'mypkg': 'src/mypkg'},
    include_package_data = True,
    package_data = {
        '': ['*.txt'],
        'mypkg': ['data/*.dat'],
    }
)
Scenario 3 doesn't work either:
from setuptools import find_packages
from setuptools.command import sdist
setup (
    name = 'mypkg',
    packages = find_packages('src'),
    package_dir = {'mypkg': 'src/mypkg'},
    include_package_data = True,
    package_data = {
        '': ['*.txt'],
        'mypkg': ['data/*.dat'],
    }
)
 
     
    