Add dedicated error message for dependencies with relative paths

[charliermarsh]

Given:

[project]
name = "foo"
version = "0.1.0"
description = "Add your description here"
readme = "README.md"
requires-python = ">=3.13.0"
dependencies = ["foo @ ./scripts/path"]

Running uv pip install -r pyproject.toml gives you:

error: Failed to parse metadata from built wheel
  Caused by: relative path without a working directory: ./scripts/path
foo@ ./scripts/path
     ^^^^^^^^^^^^^^

I think this is common enough that we should map the error to something that explains that you can't have relative paths here.

[Avasam]

Why can't one have a relative package?
pip understands it:

[dependency-groups]
dev = [
    # Utilities for typeshed infrastructure scripts.
    "ts_utils @ file:lib",
]

Running pip install --group=dev (yes I'm using a development build of pip):

Processing e:\users\avasam\documents\git\typeshed\lib
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Preparing metadata (pyproject.toml) ... done
Building wheels for collected packages: ts_utils
  Building wheel for ts_utils (pyproject.toml) ... done
  Created wheel for ts_utils: filename=ts_utils-0.0.0-py3-none-any.whl size=9799 sha256=71500cdf89a1076acc39d0b1230e7eba715e30263fbcc4f761e4365415d1776c
  Stored in directory: C:\Users\Avasam\AppData\Local\Temp\pip-ephem-wheel-cache-arsvhtxw\wheels\00\2d\32\d7e3a21f208c4a8070a33090d86b7d4485b97c106ecbd54e91
Successfully built ts_utils
Installing collected packages: ts_utils
  Attempting uninstall: ts_utils
    Found existing installation: ts_utils 0.0.0
    Uninstalling ts_utils-0.0.0:
      Successfully uninstalled ts_utils-0.0.0
Successfully installed ts_utils-0.0.0

One could do this to work on uv:

[dependency-groups]
dev = [
    # Utilities for typeshed infrastructure scripts.
    "ts_utils @ file:${PROJECT_ROOT}/lib",
]

uv sync result:

Resolved 2 packages in 3ms
Installed 1 package in 8ms
 + ts-utils==0.0.0 (from file:///E:/Users/Avasam/Documents/Git/typeshed/lib)

But now that's become incompatible with pip:

Processing e:\users\avasam\documents\git\typeshed\${project_root}\lib
ERROR: Could not install packages due to an OSError: [Errno 2] No such file or directory: 'E:\\Users\\Avasam\\Documents\\Git\\typeshed\\${PROJECT_ROOT}\\lib'

Is there a better solution or a config I'm missing ?

uv 0.6.5 (bcbcd0a1e 2025-03-06)