python-poetry/poetry · warning · ValueError

<warning>Environment "{python}" does not exist.</warning>

Error message

<warning>Environment "{python}" does not exist.</warning>

What it means

Raised as ValueError in EnvManager.remove when the given name passes the project-ownership check (it starts with base_env_name) but none of the venvs returned by self.list() has a matching path.name. I.e., the env name looks like it belongs to this project but no such virtualenv is registered.

Source

Thrown at src/poetry/utils/env/env_manager.py:308

                ):
                    raise IncorrectEnvError(env_name)
            except CalledProcessError as e:
                raise EnvCommandError(e)

        if self.check_env_is_for_current_project(python, self.base_env_name):
            venvs = self.list()
            for venv in venvs:
                if venv.path.name == python:
                    # Exact virtualenv name
                    if self.envs_file.exists():
                        venv_minor = ".".join(str(v) for v in venv.version_info[:2])
                        self.envs_file.remove_section(self.base_env_name, venv_minor)

                    self.remove_venv(venv.path)

                    return venv

            raise ValueError(
                f'<warning>Environment "{python}" does not exist.</warning>'
            )
        else:
            venv_path = self._poetry.config.virtualenvs_path
            # Get all the poetry envs, even for other projects
            env_names = [p.name for p in sorted(venv_path.glob("*-*-py*"))]
            if python in env_names:
                raise IncorrectEnvError(python)

        try:
            python_version = Version.parse(python)
            python = f"python{python_version.major}"
            if python_version.precision > 1:
                python += f".{python_version.minor}"
        except ValueError:
            # Executable in PATH or full executable path
            pass

View on GitHub (pinned to 92b74dcfe3)

Solutions

1. List actual envs for this project: 'poetry env list' and remove one that appears there.
2. If the env dir was deleted by hand, the message is effectively a no-op - nothing to remove; ignore it.
3. Check that virtualenvs_path in config still points where the env was created.
4. Recreate the env with 'poetry install' if you still need it.

Example fix

// before
manager.remove("myproject-py3.99")  # never created -> ValueError

// after - remove an env that actually exists
manager.remove("myproject-py3.11")

def env_exists_for_project(manager, name: str) -> bool:
    if not manager.check_env_is_for_current_project(name, manager.base_env_name):
        return False
    return any(venv.path.name == name for venv in manager.list())

def is_missing_env_value_error(e: Exception) -> bool:
    return isinstance(e, ValueError) and 'does not exist' in str(e)

try:
    manager.remove(name)
except ValueError as e:
    if 'does not exist' in str(e):
        # already gone - nothing to do
        pass
    else:
        raise

When it happens

Trigger: Calling 'poetry env remove <name>' where <name> matches the project prefix but the concrete venv was already deleted, never created, or lives outside the discovered virtualenvs_path. Exact branch: env_manager.py:295-310.

Common situations: The venv directory was deleted by hand (rm -rf) but the user still references it; the virtualenvs_path changed between invocations; a typo in the env name that still happens to share the prefix; running after a cache cleanup tool removed envs.

Related errors

• <warning>Environment "{name}" does not exist.</warning>
• Env {env_name} doesn't belong to this project.
• Discovered shell '{shell}' doesn't have an activator in virt
• embedded {distribution} wheel not found
• Command {e.cmd} errored with the following return code {e.re

AI-assisted analysis of python-poetry/poetry@92b74dcfe3 (2026-08-04). Data as JSON: /data/errors/ae6beb83da876954.json. Report an issue: GitHub.