Dephell vendor download does not work for single-file modules

[mariusvniekerk]

Short description

It seems as if the vendor dowload does not work for packages that are a single file like appdirs that regularly just install themselves into site-packages directly

Output

$ dephell vendor download

INFO get dependencies (format=poetry, path=pyproject.toml)
INFO build dependencies graph... 
INFO downloading packages... (output=mylib/_vendor)
ERROR cannot find modules (dependency=appdirs, version=1.4.4)
ERROR FileNotFoundError: [Errno 2] No such file or directory: 'mylib/_vendor/__init__.py' 

Expected ERROR cannot find modules (dependency=appdirs, version=1.4.4) to not be there

Steps to reproduce

$ dephell vendor download

INFO get dependencies (format=poetry, path=pyproject.toml)
INFO build dependencies graph... 
INFO downloading packages... (output=mylib/_vendor)
ERROR cannot find modules (dependency=appdirs, version=1.4.4)
ERROR FileNotFoundError: [Errno 2] No such file or directory: 'mylib/_vendor/__init__.py' 

Config

[tool.poetry]
name = "foo"
version = "0.1.0"
description = ""

[tool.poetry.dependencies]
python = "^3.6"
appdirs = "*"

[build-system]
requires = ["poetry>=0.12"]
build-backend = "poetry.masonry.api"

[tool.dephell.main]
from = {format = "poetry", path = "pyproject.toml"}

[tool.dephell.main.vendor]
path = "mylib/_vendor"
exclude = ["setuptools", "pip"]

Versions

{
  "cache": "7.72Mb",
  "path": "/Users/mvanniekerk/miniconda3/lib/python3.7/site-packages/dephell",
  "python": "/Users/mvanniekerk/miniconda3/bin/python3.7",
  "version": "0.8.3",
  "versions": {
    "dephell-archive": "0.1.7",
    "dephell-argparse": "0.1.3",
    "dephell-changelogs": "0.0.1",
    "dephell-discover": "0.2.10",
    "dephell-licenses": "0.1.7",
    "dephell-links": "0.1.5",
    "dephell-markers": "1.0.3",
    "dephell-pythons": "0.1.15",
    "dephell-setuptools": "0.2.4",
    "dephell-shells": "0.1.5",
    "dephell-specifier": "0.2.2",
    "dephell-venvs": "0.1.17",
    "dephell-versioning": "0.1.2"
  }
}