`--override` not supported by `uv run`

Using the latest uv:

$ uv --version
uv 0.2.21 (ebfe6d8fc 2024-07-03)

Use-case

I have a test workflow for my click-extra project which boils down to:

$ python -m pip install uv
$ uv venv --system
$ uv pip install --all-extras --requirement pyproject.toml .
$ uv run pytest

Everything's good as it is.

But now I want to override some of the default dependencies specified in pyproject.toml. My use-case is to test unreleased upstream dependencies, so I can anticipate upcoming breaking changes.

What I used to do with Poetry was to locally add these new dependencies as-is:

$ poetry add git+https://github.com/pallets/click.git#main

Migrating to uv, my new workflow looks like this:

$ uv venv --system
$ uv pip install --all-extras --requirement pyproject.toml .
$ uv pip install "git+https://github.com/pallets/click.git#main"
$ uv run pytest

But this doesn't work as I expected. As soon as I call uv run pytest, the locally installed Click is discarded, and replaced by the canonical requirement from pyproject.toml:

$ cat pyproject.toml
[project]
name = "click-extra"
version = "4.8.4"
dependencies = [
    "click ~= 8.1.4",
(...)

See how I installed the click==8.2.0.dev0 version I am looking for:

$ uv pip install --all-extras --requirement pyproject.toml .
Resolved 72 packages in 2.20s
Audited 72 packages in 0.63ms

$ uv pip tree | grep click
click-extra v4.8.4
├── click v8.1.7
│   └── click v8.1.7

$ uv pip install "git+https://github.com/pallets/click.git#main"
 Updated https://github.com/pallets/click.git (14f735c)
Resolved 1 package in 1.86s
Uninstalled 1 package in 4ms
Installed 1 package in 2ms
 - click==8.1.7
 + click==8.2.0.dev0 (from git+https://github.com/pallets/click.git@14f735cf59618941cf2930e633eb77651b1dc7cb)

And then have uv run pytest re-installing back click==8.1.7:

$ uv run pytest
warning: `uv run` is experimental and may change without warning.
Resolved 77 packages in 890ms
   Built click-extra @ file:///Users/kde/click-extra
Prepared 1 package in 1.06s
Uninstalled 2 packages in 3ms
Installed 2 packages in 2ms
 - click==8.2.0.dev0 (from git+https://github.com/pallets/click.git@14f735cf59618941cf2930e633eb77651b1dc7cb)
 + click==8.1.7
 - click-extra==4.8.4 (from file:///Users/kde/click-extra)
 + click-extra==4.8.4 (from file:///Users/kde/click-extra)
================== test session starts ==================
platform darwin -- Python 3.12.4, pytest-8.2.2, pluggy-1.5.0
(...)

--override workaround

Digging into uv help, I stumble upon the --override option, which seems to be the way to do what I want.

So I now have:

$ cat ./overrides.txt
click @ git+https://github.com/pallets/click.git#main

And using it ends up with the right dependencies:

$ uv pip install --all-extras --requirement pyproject.toml --override ./overrides.txt .

 Updated https://github.com/pallets/click.git (14f735c)
Resolved 72 packages in 4.15s
   Built click-extra @ file:///Users/kde/click-extra
Prepared 1 package in 765ms
Uninstalled 2 packages in 3ms
Installed 2 packages in 1ms
 - click==8.1.7
 + click==8.2.0.dev0 (from git+https://github.com/pallets/click.git@14f735cf59618941cf2930e633eb77651b1dc7cb)
 - click-extra==4.8.4 (from file:///Users/kde/click-extra)
 + click-extra==4.8.4 (from file:///Users/kde/click-extra)

$ uv pip tree | grep click
click-extra v4.8.4
├── click v8.2.0.dev0
│   └── click v8.2.0.dev0

Which seems to do the trick. But again, uv run is reverting my override:

$ uv run pytest
warning: `uv run` is experimental and may change without warning.
Resolved 77 packages in 1.00s
   Built click-extra @ file:///Users/kde/click-extra
Prepared 1 package in 558ms
Uninstalled 2 packages in 1ms
Installed 2 packages in 2ms
 - click==8.2.0.dev0 (from git+https://github.com/pallets/click.git@14f735cf59618941cf2930e633eb77651b1dc7cb)
 + click==8.1.7
 - click-extra==4.8.4 (from file:///Users/kde/click-extra)
 + click-extra==4.8.4 (from file:///Users/kde/click-extra)
================== test session starts ==================
platform darwin -- Python 3.12.4, pytest-8.2.2, pluggy-1.5.0
(...)

--override not supported by uv run

So maybe I need to use --override on uv run. But it is not supported:

$ uv run --override ./overrides.txt pytest
error: unexpected argument '--override' found

  tip: a similar argument exists: '--preview'

Usage: uv run [OPTIONS] <COMMAND>

For more information, try '--help'.

$ uv --override ./overrides.txt run pytest
error: unexpected argument '--override' found

  tip: a similar argument exists: '--preview'

Usage: uv <--quiet|--verbose...|--no-color|--color <COLOR_CHOICE>|--native-tls|--no-native-tls|--offline|--no-offline|--toolchain-preference <TOOLCHAIN_PREFERENCE>|--toolchain-fetch <TOOLCHAIN_FETCH>|--preview|--no-preview|--isolated|--show-settings> <COMMAND>

For more information, try '--help'.

Should we requalify this ticket into a feature request to have --override supported by the run subcommand?

New --no-upgrade option for uv run?

Another alternative is maybe to have a --no-upgrade option on uv run to tell it to not make any changes to the currently installed dependencies.

That might be the opposite of the existing -U/--upgrade parameter:

  -U, --upgrade
          Allow package upgrades, ignoring pinned versions in any existing output file