pypa/pip · error · InstallationError

Editable requirements are not allowed as constraints

Error message

Editable requirements are not allowed as constraints

What it means

Raised by install_req_from_editable() when an editable requirement is also flagged as a constraint (constraint=True). pip's constraint files (-c constraints.txt) may only pin versions of regular requirements; editable installs are fundamentally unversioned source checkouts, so combining -e with -c is nonsensical and rejected at constructors.py:265.

Source

Thrown at src/pip/_internal/req/constructors.py:265

    return RequirementParts(req, link, None, extras_override)


# ---- The actual constructors follow ----


def install_req_from_editable(
    editable_req: str,
    comes_from: InstallRequirement | str | None = None,
    *,
    isolated: bool = False,
    hash_options: dict[str, list[str]] | None = None,
    constraint: bool = False,
    user_supplied: bool = False,
    config_settings: dict[str, str | list[str]] | None = None,
) -> InstallRequirement:
    if constraint:
        raise InstallationError("Editable requirements are not allowed as constraints")

    parts = parse_req_from_editable(editable_req)
    return InstallRequirement(
        parts.requirement,
        comes_from=comes_from,
        user_supplied=user_supplied,
        editable=True,
        link=parts.link,
        constraint=constraint,
        isolated=isolated,
        hash_options=hash_options,
        config_settings=config_settings,
        extras=parts.extras,
    )


def _looks_like_path(name: str) -> bool:
    """Checks whether the string "looks like" a path on the filesystem.

View on GitHub (pinned to d7d0d0a394)

Solutions

1. Remove the `-e` prefix from any line inside a constraints file; constraints must be plain version-pinning specifiers.
2. If you need the editable install, move that line into the main requirements file (passed with -r), not the constraints file (-c).
3. If you meant to constrain a normal dependency, drop -e and specify a version, e.g. `package==1.2.3`.

Example fix

# before (constraints.txt)
-e ./local_project
# after (move to requirements.txt)
-e ./local_project
# constraints.txt should only contain version pins like:
# somepackage==1.2.3

def assert_not_editable_constraint(spec: str, is_constraint: bool) -> None:
    if is_constraint and spec.startswith("-e "):
        raise ValueError("Editable requirements cannot be used as constraints")

null

null

When it happens

Trigger: Putting a `-e ./path` or `-e git+...` line inside a constraints file passed via `pip install -c constraints.txt`. Or programmatically calling install_req_from_editable(..., constraint=True).

Common situations: Attempting to pin a local checkout's version via a constraints file. Migrating a requirements file to constraints and forgetting to remove -e lines. Misunderstanding that constraints constrain versions, not source locations.

Related errors

• {editable_req} is not a valid editable requirement. It shoul
• Could not detect requirement name for '{editable_req}', plea
• Invalid requirement: {name!r}: {exc}
• Directory {name!r} is not installable. Neither 'setup.py' no
• Invalid requirement: {req_as_string!r}: {exc}

AI-assisted analysis of pypa/pip@d7d0d0a394 (2026-08-04). Data as JSON: /data/errors/14335efc1ae48df2.json. Report an issue: GitHub.