import os
import shutil
import sys

from typing import Optional
from typing import Union

import pytest
import tomlkit

from clikit.io import NullIO

from poetry.core.semver import Version
from poetry.factory import Factory
from poetry.utils._compat import PY2
from poetry.utils._compat import Path
from poetry.utils.env import EnvCommandError
from poetry.utils.env import EnvManager
from poetry.utils.env import NoCompatiblePythonVersionFound
from poetry.utils.env import SystemEnv
from poetry.utils.env import VirtualEnv
from poetry.utils.toml_file import TomlFile


MINIMAL_SCRIPT = """\

print("Minimal Output"),
"""

# Script expected to fail.
ERRORING_SCRIPT = """\
import nullpackage

print("nullpackage loaded"),
"""


class MockVirtualEnv(VirtualEnv):
    def __init__(self, path, base=None, sys_path=None):
        super(MockVirtualEnv, self).__init__(path, base=base)

        self._sys_path = sys_path

    @property
    def sys_path(self):
        if self._sys_path is not None:
            return self._sys_path

        return super(MockVirtualEnv, self).sys_path


@pytest.fixture()
def poetry(config):
    poetry = Factory().create_poetry(
        Path(__file__).parent.parent / "fixtures" / "simple_project"
    )
    poetry.set_config(config)

    return poetry


@pytest.fixture()
def manager(poetry):
    return EnvManager(poetry)


def test_virtualenvs_with_spaces_in_their_path_work_as_expected(tmp_dir, manager):
    venv_path = Path(tmp_dir) / "Virtual Env"

    manager.build_venv(str(venv_path))

    venv = VirtualEnv(venv_path)

    assert venv.run("python", "-V", shell=True).startswith("Python")


def test_env_get_in_project_venv(manager, poetry):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    (poetry.file.parent / ".venv").mkdir()

    venv = manager.get()

    assert venv.path == poetry.file.parent / ".venv"

    shutil.rmtree(str(venv.path))


def build_venv(path, executable=None):  # type: (Union[Path,str], Optional[str]) -> ()
    os.mkdir(str(path))


def check_output_wrapper(version=Version.parse("3.7.1")):
    def check_output(cmd, *args, **kwargs):
        if "sys.version_info[:3]" in cmd:
            return version.text
        elif "sys.version_info[:2]" in cmd:
            return "{}.{}".format(version.major, version.minor)
        else:
            return str(Path("/prefix"))

    return check_output


def test_activate_activates_non_existing_virtualenv_no_envs_file(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None), ("/prefix", None)],
    )
    m = mocker.patch("poetry.utils.env.EnvManager.build_venv", side_effect=build_venv)

    env = manager.activate("python3.7", NullIO())
    venv_name = EnvManager.generate_env_name("simple-project", str(poetry.file.parent))

    m.assert_called_with(
        Path(tmp_dir) / "{}-py3.7".format(venv_name), executable="python3.7"
    )

    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    assert envs_file.exists()
    envs = envs_file.read()
    assert envs[venv_name]["minor"] == "3.7"
    assert envs[venv_name]["patch"] == "3.7.1"

    assert env.path == Path(tmp_dir) / "{}-py3.7".format(venv_name)
    assert env.base == Path("/prefix")


def test_activate_activates_existing_virtualenv_no_envs_file(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    os.mkdir(os.path.join(tmp_dir, "{}-py3.7".format(venv_name)))

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None)],
    )
    m = mocker.patch("poetry.utils.env.EnvManager.build_venv", side_effect=build_venv)

    env = manager.activate("python3.7", NullIO())

    m.assert_not_called()

    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    assert envs_file.exists()
    envs = envs_file.read()
    assert envs[venv_name]["minor"] == "3.7"
    assert envs[venv_name]["patch"] == "3.7.1"

    assert env.path == Path(tmp_dir) / "{}-py3.7".format(venv_name)
    assert env.base == Path("/prefix")


def test_activate_activates_same_virtualenv_with_envs_file(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {"minor": "3.7", "patch": "3.7.1"}
    envs_file.write(doc)

    os.mkdir(os.path.join(tmp_dir, "{}-py3.7".format(venv_name)))

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None)],
    )
    m = mocker.patch("poetry.utils.env.EnvManager.create_venv")

    env = manager.activate("python3.7", NullIO())

    m.assert_not_called()

    assert envs_file.exists()
    envs = envs_file.read()
    assert envs[venv_name]["minor"] == "3.7"
    assert envs[venv_name]["patch"] == "3.7.1"

    assert env.path == Path(tmp_dir) / "{}-py3.7".format(venv_name)
    assert env.base == Path("/prefix")


def test_activate_activates_different_virtualenv_with_envs_file(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {"minor": "3.7", "patch": "3.7.1"}
    envs_file.write(doc)

    os.mkdir(os.path.join(tmp_dir, "{}-py3.7".format(venv_name)))

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.6")),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None), ("/prefix", None), ("/prefix", None)],
    )
    m = mocker.patch("poetry.utils.env.EnvManager.build_venv", side_effect=build_venv)

    env = manager.activate("python3.6", NullIO())

    m.assert_called_with(
        Path(tmp_dir) / "{}-py3.6".format(venv_name), executable="python3.6"
    )

    assert envs_file.exists()
    envs = envs_file.read()
    assert envs[venv_name]["minor"] == "3.6"
    assert envs[venv_name]["patch"] == "3.6.6"

    assert env.path == Path(tmp_dir) / "{}-py3.6".format(venv_name)
    assert env.base == Path("/prefix")


def test_activate_activates_recreates_for_different_patch(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {"minor": "3.7", "patch": "3.7.0"}
    envs_file.write(doc)

    os.mkdir(os.path.join(tmp_dir, "{}-py3.7".format(venv_name)))

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[
            ("/prefix", None),
            ('{"version_info": [3, 7, 0]}', None),
            ("/prefix", None),
            ("/prefix", None),
            ("/prefix", None),
        ],
    )
    build_venv_m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=build_venv
    )
    remove_venv_m = mocker.patch(
        "poetry.utils.env.EnvManager.remove_venv", side_effect=EnvManager.remove_venv
    )

    env = manager.activate("python3.7", NullIO())

    build_venv_m.assert_called_with(
        Path(tmp_dir) / "{}-py3.7".format(venv_name), executable="python3.7"
    )
    remove_venv_m.assert_called_with(Path(tmp_dir) / "{}-py3.7".format(venv_name))

    assert envs_file.exists()
    envs = envs_file.read()
    assert envs[venv_name]["minor"] == "3.7"
    assert envs[venv_name]["patch"] == "3.7.1"

    assert env.path == Path(tmp_dir) / "{}-py3.7".format(venv_name)
    assert env.base == Path("/prefix")
    assert (Path(tmp_dir) / "{}-py3.7".format(venv_name)).exists()


def test_activate_does_not_recreate_when_switching_minor(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {"minor": "3.7", "patch": "3.7.0"}
    envs_file.write(doc)

    os.mkdir(os.path.join(tmp_dir, "{}-py3.7".format(venv_name)))
    os.mkdir(os.path.join(tmp_dir, "{}-py3.6".format(venv_name)))

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.6")),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None), ("/prefix", None), ("/prefix", None)],
    )
    build_venv_m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=build_venv
    )
    remove_venv_m = mocker.patch(
        "poetry.utils.env.EnvManager.remove_venv", side_effect=EnvManager.remove_venv
    )

    env = manager.activate("python3.6", NullIO())

    build_venv_m.assert_not_called()
    remove_venv_m.assert_not_called()

    assert envs_file.exists()
    envs = envs_file.read()
    assert envs[venv_name]["minor"] == "3.6"
    assert envs[venv_name]["patch"] == "3.6.6"

    assert env.path == Path(tmp_dir) / "{}-py3.6".format(venv_name)
    assert env.base == Path("/prefix")
    assert (Path(tmp_dir) / "{}-py3.6".format(venv_name)).exists()


def test_deactivate_non_activated_but_existing(
    tmp_dir, manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    (
        Path(tmp_dir)
        / "{}-py{}".format(venv_name, ".".join(str(c) for c in sys.version_info[:2]))
    ).mkdir()

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )

    manager.deactivate(NullIO())
    env = manager.get()

    assert env.path == Path(tmp_dir) / "{}-py{}".format(
        venv_name, ".".join(str(c) for c in sys.version_info[:2])
    )
    assert Path("/prefix")


def test_deactivate_activated(tmp_dir, manager, poetry, config, mocker):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    version = Version.parse(".".join(str(c) for c in sys.version_info[:3]))
    other_version = Version.parse("3.4") if version.major == 2 else version.next_minor
    (
        Path(tmp_dir) / "{}-py{}.{}".format(venv_name, version.major, version.minor)
    ).mkdir()
    (
        Path(tmp_dir)
        / "{}-py{}.{}".format(venv_name, other_version.major, other_version.minor)
    ).mkdir()

    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {
        "minor": "{}.{}".format(other_version.major, other_version.minor),
        "patch": other_version.text,
    }
    envs_file.write(doc)

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )

    manager.deactivate(NullIO())
    env = manager.get()

    assert env.path == Path(tmp_dir) / "{}-py{}.{}".format(
        venv_name, version.major, version.minor
    )
    assert Path("/prefix")

    envs = envs_file.read()
    assert len(envs) == 0


def test_get_prefers_explicitly_activated_virtualenvs_over_env_var(
    tmp_dir, manager, poetry, config, mocker
):
    os.environ["VIRTUAL_ENV"] = "/environment/prefix"

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    config.merge({"virtualenvs": {"path": str(tmp_dir)}})
    (Path(tmp_dir) / "{}-py3.7".format(venv_name)).mkdir()

    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {"minor": "3.7", "patch": "3.7.0"}
    envs_file.write(doc)

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None)],
    )

    env = manager.get()

    assert env.path == Path(tmp_dir) / "{}-py3.7".format(venv_name)
    assert env.base == Path("/prefix")


def test_list(tmp_dir, manager, poetry, config):
    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    (Path(tmp_dir) / "{}-py3.7".format(venv_name)).mkdir()
    (Path(tmp_dir) / "{}-py3.6".format(venv_name)).mkdir()

    venvs = manager.list()

    assert 2 == len(venvs)
    assert (Path(tmp_dir) / "{}-py3.6".format(venv_name)) == venvs[0].path
    assert (Path(tmp_dir) / "{}-py3.7".format(venv_name)) == venvs[1].path


def test_remove_by_python_version(tmp_dir, manager, poetry, config, mocker):
    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    (Path(tmp_dir) / "{}-py3.7".format(venv_name)).mkdir()
    (Path(tmp_dir) / "{}-py3.6".format(venv_name)).mkdir()

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.6")),
    )

    venv = manager.remove("3.6")

    assert (Path(tmp_dir) / "{}-py3.6".format(venv_name)) == venv.path
    assert not (Path(tmp_dir) / "{}-py3.6".format(venv_name)).exists()


def test_remove_by_name(tmp_dir, manager, poetry, config, mocker):
    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    (Path(tmp_dir) / "{}-py3.7".format(venv_name)).mkdir()
    (Path(tmp_dir) / "{}-py3.6".format(venv_name)).mkdir()

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.6")),
    )

    venv = manager.remove("{}-py3.6".format(venv_name))

    assert (Path(tmp_dir) / "{}-py3.6".format(venv_name)) == venv.path
    assert not (Path(tmp_dir) / "{}-py3.6".format(venv_name)).exists()


def test_remove_also_deactivates(tmp_dir, manager, poetry, config, mocker):
    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    (Path(tmp_dir) / "{}-py3.7".format(venv_name)).mkdir()
    (Path(tmp_dir) / "{}-py3.6".format(venv_name)).mkdir()

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.6")),
    )

    envs_file = TomlFile(Path(tmp_dir) / "envs.toml")
    doc = tomlkit.document()
    doc[venv_name] = {"minor": "3.6", "patch": "3.6.6"}
    envs_file.write(doc)

    venv = manager.remove("python3.6")

    assert (Path(tmp_dir) / "{}-py3.6".format(venv_name)) == venv.path
    assert not (Path(tmp_dir) / "{}-py3.6".format(venv_name)).exists()

    envs = envs_file.read()
    assert venv_name not in envs


def test_remove_keeps_dir_if_not_deleteable(tmp_dir, manager, poetry, config, mocker):
    # Ensure we empty rather than delete folder if its is an active mount point.
    # See https://github.com/python-poetry/poetry/pull/2064
    config.merge({"virtualenvs": {"path": str(tmp_dir)}})

    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))
    venv_path = Path(tmp_dir) / "{}-py3.6".format(venv_name)
    venv_path.mkdir()

    folder1_path = venv_path / "folder1"
    folder1_path.mkdir()

    file1_path = folder1_path / "file1"
    file1_path.touch(exist_ok=False)

    file2_path = venv_path / "file2"
    file2_path.touch(exist_ok=False)

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.6")),
    )

    original_rmtree = shutil.rmtree

    def err_on_rm_venv_only(path, *args, **kwargs):
        if path == str(venv_path):
            raise OSError(16, "Test error")  # ERRNO 16: Device or resource busy
        else:
            original_rmtree(path)

    m = mocker.patch("shutil.rmtree", side_effect=err_on_rm_venv_only)

    venv = manager.remove("{}-py3.6".format(venv_name))

    m.assert_any_call(str(venv_path))

    assert venv_path == venv.path
    assert venv_path.exists()

    assert not folder1_path.exists()
    assert not file1_path.exists()
    assert not file2_path.exists()

    m.side_effect = original_rmtree  # Avoid teardown using `err_on_rm_venv_only`


@pytest.mark.skipif(
    os.name == "nt" or PY2, reason="Symlinks are not support for Windows"
)
def test_env_has_symlinks_on_nix(tmp_dir, tmp_venv):
    assert os.path.islink(tmp_venv.python)


def test_run_with_input(tmp_dir, tmp_venv):
    result = tmp_venv.run("python", "-", input_=MINIMAL_SCRIPT)

    assert result == "Minimal Output" + os.linesep


def test_run_with_input_non_zero_return(tmp_dir, tmp_venv):

    with pytest.raises(EnvCommandError) as processError:
        # Test command that will return non-zero returncode.
        tmp_venv.run("python", "-", input_=ERRORING_SCRIPT)

    assert processError.value.e.returncode == 1


def test_create_venv_tries_to_find_a_compatible_python_executable_using_generic_ones_first(
    manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    poetry.package.python_versions = "^3.6"
    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    mocker.patch("sys.version_info", (2, 7, 16))
    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.7.5")),
    )
    m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=lambda *args, **kwargs: ""
    )

    manager.create_venv(NullIO())

    m.assert_called_with(
        Path("/foo/virtualenvs/{}-py3.7".format(venv_name)), executable="python3"
    )


def test_create_venv_tries_to_find_a_compatible_python_executable_using_specific_ones(
    manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    poetry.package.python_versions = "^3.6"
    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    mocker.patch("sys.version_info", (2, 7, 16))
    mocker.patch(
        "poetry.utils._compat.subprocess.check_output", side_effect=["3.5.3", "3.9.0"]
    )
    m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=lambda *args, **kwargs: ""
    )

    manager.create_venv(NullIO())

    m.assert_called_with(
        Path("/foo/virtualenvs/{}-py3.9".format(venv_name)), executable="python3.9"
    )


def test_create_venv_fails_if_no_compatible_python_version_could_be_found(
    manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    poetry.package.python_versions = "^4.8"

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output", side_effect=["", "", "", ""]
    )
    m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=lambda *args, **kwargs: ""
    )

    with pytest.raises(NoCompatiblePythonVersionFound) as e:
        manager.create_venv(NullIO())

    expected_message = (
        "Poetry was unable to find a compatible version. "
        "If you have one, you can explicitly use it "
        'via the "env use" command.'
    )

    assert expected_message == str(e.value)
    assert 0 == m.call_count


def test_create_venv_does_not_try_to_find_compatible_versions_with_executable(
    manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    poetry.package.python_versions = "^4.8"

    mocker.patch("poetry.utils._compat.subprocess.check_output", side_effect=["3.8.0"])
    m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=lambda *args, **kwargs: ""
    )

    with pytest.raises(NoCompatiblePythonVersionFound) as e:
        manager.create_venv(NullIO(), executable="3.8")

    expected_message = (
        "The specified Python version (3.8.0) is not supported by the project (^4.8).\n"
        "Please choose a compatible version or loosen the python constraint "
        "specified in the pyproject.toml file."
    )

    assert expected_message == str(e.value)
    assert 0 == m.call_count


def test_create_venv_uses_patch_version_to_detect_compatibility(
    manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    version = Version.parse(".".join(str(c) for c in sys.version_info[:3]))
    poetry.package.python_versions = "^{}".format(
        ".".join(str(c) for c in sys.version_info[:3])
    )
    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    mocker.patch("sys.version_info", (version.major, version.minor, version.patch + 1))
    check_output = mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(Version.parse("3.6.9")),
    )
    m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=lambda *args, **kwargs: ""
    )

    manager.create_venv(NullIO())

    assert not check_output.called
    m.assert_called_with(
        Path(
            "/foo/virtualenvs/{}-py{}.{}".format(
                venv_name, version.major, version.minor
            )
        ),
        executable=None,
    )


def test_create_venv_uses_patch_version_to_detect_compatibility_with_executable(
    manager, poetry, config, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    version = Version.parse(".".join(str(c) for c in sys.version_info[:3]))
    poetry.package.python_versions = "~{}".format(
        ".".join(str(c) for c in (version.major, version.minor - 1, 0))
    )
    venv_name = manager.generate_env_name("simple-project", str(poetry.file.parent))

    check_output = mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(
            Version.parse("{}.{}.0".format(version.major, version.minor - 1))
        ),
    )
    m = mocker.patch(
        "poetry.utils.env.EnvManager.build_venv", side_effect=lambda *args, **kwargs: ""
    )

    manager.create_venv(
        NullIO(), executable="python{}.{}".format(version.major, version.minor - 1)
    )

    assert check_output.called
    m.assert_called_with(
        Path(
            "/foo/virtualenvs/{}-py{}.{}".format(
                venv_name, version.major, version.minor - 1
            )
        ),
        executable="python{}.{}".format(version.major, version.minor - 1),
    )


def test_activate_with_in_project_setting_does_not_fail_if_no_venvs_dir(
    manager, poetry, config, tmp_dir, mocker
):
    if "VIRTUAL_ENV" in os.environ:
        del os.environ["VIRTUAL_ENV"]

    config.merge(
        {
            "virtualenvs": {
                "path": str(Path(tmp_dir) / "virtualenvs"),
                "in-project": True,
            }
        }
    )

    mocker.patch(
        "poetry.utils._compat.subprocess.check_output",
        side_effect=check_output_wrapper(),
    )
    mocker.patch(
        "poetry.utils._compat.subprocess.Popen.communicate",
        side_effect=[("/prefix", None), ("/prefix", None)],
    )
    m = mocker.patch("poetry.utils.env.EnvManager.build_venv")

    manager.activate("python3.7", NullIO())

    m.assert_called_with(poetry.file.parent / ".venv", executable="python3.7")

    envs_file = TomlFile(Path(tmp_dir) / "virtualenvs" / "envs.toml")
    assert not envs_file.exists()


def test_system_env_has_correct_paths():
    env = SystemEnv(Path(sys.prefix))

    paths = env.paths

    assert paths.get("purelib") is not None
    assert paths.get("platlib") is not None
    assert paths.get("scripts") is not None
    assert env.site_packages == Path(paths["purelib"])


def test_venv_has_correct_paths(tmp_venv):
    paths = tmp_venv.paths

    assert paths.get("purelib") is not None
    assert paths.get("platlib") is not None
    assert paths.get("scripts") is not None
    assert tmp_venv.site_packages == Path(paths["purelib"])
