contents() of a zip file package returns incorrect results

Packages (directories) inside .pyz archives seem to confuse importlib_resources 0.1.

importlib_resources.contents() can return content for unrelated directories -- even for directories that aren't packages.
importlib_resources.read() fails to find resources that .contents() found -- even those that are in the archive.

Here is reproducer -- run on a *nix, in an empty directory, with importlib_resources installed:

#! /bin/bash -ex

rm -rf demo.pyz demo unrelated

mkdir demo

echo "
import importlib_resources

def main():
    for resource in sorted(importlib_resources.contents(__name__)):
        print('Resource:', resource)

    for resource in sorted(importlib_resources.contents(__name__)):
        print('Reading:', resource)
        importlib_resources.read(__name__, resource)
" > demo/__init__.py

echo > demo/resource.txt

mkdir unrelated
echo > unrelated/unrelated_resource.txt

python -m zipapp -o demo.pyz . -m demo:main

python demo.pyz

Result:

Resource: __init__.py
Resource: resource.txt
Resource: unrelated_resource.txt
Reading: __init__.py
Traceback (most recent call last):
  ...
FileNotFoundError: '__init__.py' resource not found in 'demo'

Expected (and what I get when I use pkg_resources by “anti-following” the Migration Guide):

Resource: __init__.py
Resource: resource.txt
Reading: __init__.py
357
Reading: resource.txt
1