##### SUMMARY
If you have executable files in your source code they are not kept in the tarball.

Could be related to https://github.com/ansible/ansible/blob/99d7f150873011e7515851db9b44ff486efa9d77/lib/ansible/galaxy/collection.py#L763

This was noticed as I had some auxiliary scripts in my repo.

Need to also consider scripts in `files/` if/when Collections support roles.

This seems to fail the "principal of least suprise"

**Proposal 1: Keep on stripping executable flags**

Add some line to the output
`WARNING: tests/coverage.sh: source file has executable flag, though this will be ignored in generated tar.gz`
Update developing a collection documentation page
Update integration tests to ensure that executable mode is always stripped.
Update code to link to this issue

**Proposal 2: Allow executible flags**

Update developing a collection documentation page
Update integration tests to ensure that executable mode is preserved
Update code to link to this issue
Changelog


##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
ansible-galaxy

##### ANSIBLE VERSION
```paste below
2.10
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml

```

<!--- HINT: You can paste gist.github.com links for larger files -->


collection_path, collection_tar = collection_artifact
    temp_path = os.path.split(collection_tar)[0]
    shutil.rmtree(collection_path)
    mock_display = MagicMock()
    monkeypatch.setattr(Display, 'display', mock_display)
    collection.install_collections([(to_text(collection_tar), '*', None,)], to_text(temp_path),
                                   [u'https://galaxy.ansible.com'], True, False, False, False, False)
    assert os.path.isdir(collection_path)
    actual_files = os.listdir(collection_path)
    actual_files.sort()
    assert actual_files == [b'FILES.json', b'MANIFEST.json', b'README.md', b'docs', b'playbooks', b'plugins', b'roles']
    with open(os.path.join(collection_path, b'MANIFEST.json'), 'rb') as manifest_obj:
        actual_manifest = json.loads(to_text(manifest_obj.read()))
    assert actual_manifest['collection_info']['namespace'] == 'ansible_namespace'
    assert actual_manifest['collection_info']['name'] == 'collection'
    assert actual_manifest['collection_info']['version'] == '0.1.0'
    # Filter out the progress cursor display calls.
    display_msgs = [m[1][0] for m in mock_display.mock_calls if 'newline' not in m[2] and len(m[1]) == 1]
    assert len(display_msgs) == 3
    assert display_msgs[0] == "Process install dependency map"
    assert display_msgs[1] == "Starting collection install process"
    assert display_msgs[2] == "Installing 'ansible_namespace.collection:0.1.0' to '%s'" % to_text(collection_path)
def test_install_collections_existing_without_force(collection_artifact, monkeypatch):