[Feature Request] Add uv venv --activate to activate virtual environment after creation

[imbev]

I suggest that uv add an --activate option to the uv venv command. This option would automatically activate the virtual environment after creating it.

The following would be mostly equivalent:

uv venv
source .venv/bin/activate # Or shell equivalent

uv venv --activate

Currently, uv venv has the following output:

Using Python 3.12.6 interpreter at: /usr/bin/python3
Creating virtualenv at: .venv
Activate with: source .venv/bin/activate

This should be replaced by the following, but only with --activate:

Using Python 3.12.6 interpreter at: /usr/bin/python3
Creating virtualenv at: .venv
Activating virtualenv at: .venv

[zanieb]

Unfortunately we can't do this because of how shells work. You need to run the activation command from your shell, a subprocess cannot mutate your shell.

[Werni2A]

Something related to this request that is probably not worth creating a separate issue.

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Remembering the activation script location is confusing when switching between Windows and Linux systems. Windows makes it even worse with separate scripts for PowerShell and Command Prompt.

E.g.

• foobar\Scripts\activate.ps1 (Windows PowerShell)
• foobar\Scripts\activate (Windows Command Prompt)
• foobar/bin/activate (Linux)

Sometimes it would be useful get the activation script path directly from uv to call or source it. E.g. with a imaginary argument --activation-script.

source $(uv venv foobar --activation-script)
# Leading to
# source "foobar/bin/activate"

Since uv already provides the exact command to activate the environment it's just copy and paste in an interactive environment. I.e. the benefit would be negligible but could make scripts a bit more consistent across shell implementations.

Nothing I personally require - just something that came to mind while reading this post.

[Ravencentric]

This is also what PDM went with, i.e., a command to print the activate command for your current OS and shell.

[Kilo59]

@zanieb
Both poetry and pipenv have a shell commands that works equivalent to this proposal.
Why can't uv do something similar?

[Ravencentric]

Poetry is removing their shell command in the next major update. python-poetry/poetry#9136

[zanieb]

See #1910