Example in the Documentation does not work for Torch and TorchVision

Description

My pyproject.toml file (based on documentation )

[project]
authors = [{ name = "rohanmohapatra", email = "censored" }]
description = ""
name = "censored"
readme = "README.md"
requires-python = ">=3.10,<3.13"
version = "0.0.1"

[tool.poetry]
package-mode = false

[project.optional-dependencies]
cpu = ["torch (==2.4.1+cpu)", "torchvision (==0.19.1+cpu)"]
cuda = ["torch (==2.4.1+cu124)", "torchvision (==0.19.1+cu124)"]

[[tool.poetry.source]]
name = "pytorch-cpu"
priority = "explicit"
url = "https://download.pytorch.org/whl/cpu"

[[tool.poetry.source]]
name = "pytorch-cu124"
priority = "explicit"
url = "https://download.pytorch.org/whl/cu124"


[tool.poetry.dependencies]
torch = [
    { markers = "extra == 'cpu' and extra != 'cuda'", version = "2.4.1+cpu", source = "pytorch-cpu" },
    { markers = "extra == 'cuda' and extra != 'cpu'", version = "2.4.1+cu124", source = "pytorch-cu124" },
]
torchvision = [
    { markers = "extra == 'cpu' and extra != 'cuda'", version = "0.19.1+cpu", source = "pytorch-cpu" },
    { markers = "extra == 'cuda' and extra != 'cpu'", version = "0.19.1+cu124", source = "pytorch-cu124" },
]

When I run poetry install --extras "cuda", It shows 2 updates which is exactly what I want

Package operations: 0 installs, 2 updates, 0 removals

  - Updating torch (2.4.1+cpu -> 2.4.1+cu124)
  - Updating torchvision (0.19.1+cpu -> 0.19.1+cu124)

But when I run poetry install --extras "cpu", it shows only 1 update

Package operations: 0 installs, 1 update, 0 removals

  - Downgrading torch (2.4.1+cu124 -> 2.4.1+cpu)

This does not makes sense? Am I doing something wrong?

Workarounds

No workaround yet.

Poetry Installation Method

pip

Operating System

Ubuntu 22.04

Poetry Version

2.1.2

Poetry Configuration

cache-dir = "~/.cache/pypoetry"
data-dir = "~/.local/share/pypoetry"
installer.max-workers = null
installer.no-binary = null
installer.only-binary = null
installer.parallel = true
installer.re-resolve = true
keyring.enabled = true
python.installation-dir = "{data-dir}/python" 
repositories.pytorch-cpu.url = "https://download.pytorch.org/whl/cpu"
repositories.pytorch-cu124.url = "https://download.pytorch.org/whl/cu124"
requests.max-retries = 0
solver.lazy-wheel = true
system-git-client = false
virtualenvs.create = true
virtualenvs.in-project = null
virtualenvs.options.always-copy = false
virtualenvs.options.no-pip = false
virtualenvs.options.system-site-packages = false
virtualenvs.path = "{cache-dir}/virtualenvs"
virtualenvs.prompt = "{project_name}-py{python_version}"
virtualenvs.use-poetry-python = false

Python Sysconfig

Paste the output of 'python -m sysconfig', over this line.

Example pyproject.toml

[project]
authors = [{ name = "rohanmohapatra", email = "censored" }]
description = ""
name = "censored"
readme = "README.md"
requires-python = ">=3.10,<3.13"
version = "0.0.1"

[tool.poetry]
package-mode = false

[project.optional-dependencies]
cpu = ["torch (==2.4.1+cpu)", "torchvision (==0.19.1+cpu)"]
cuda = ["torch (==2.4.1+cu124)", "torchvision (==0.19.1+cu124)"]

[[tool.poetry.source]]
name = "pytorch-cpu"
priority = "explicit"
url = "https://download.pytorch.org/whl/cpu"

[[tool.poetry.source]]
name = "pytorch-cu124"
priority = "explicit"
url = "https://download.pytorch.org/whl/cu124"


[tool.poetry.dependencies]
torch = [
    { markers = "extra == 'cpu' and extra != 'cuda'", version = "2.4.1+cpu", source = "pytorch-cpu" },
    { markers = "extra == 'cuda' and extra != 'cpu'", version = "2.4.1+cu124", source = "pytorch-cu124" },
]
torchvision = [
    { markers = "extra == 'cpu' and extra != 'cuda'", version = "0.19.1+cpu", source = "pytorch-cpu" },
    { markers = "extra == 'cuda' and extra != 'cpu'", version = "0.19.1+cu124", source = "pytorch-cu124" },
]

Poetry Runtime Logs

Checking keyring availability: Checking if keyring is available
[keyring:keyring.backend] Loading KWallet
[keyring:keyring.backend] Loading SecretService
[keyring:keyring.backend] Loading Windows
[keyring:keyring.backend] Loading chainer
[keyring:keyring.backend] Loading libsecret
[keyring:keyring.backend] Loading macOS
Backend 'fail Keyring' is not suitable
No valid keyring backend was found
Unavailable
Installing dependencies from lock file

Finding the necessary packages for the current system

Package operations: 0 installs, 1 update, 0 removals, 11 skipped

- Downgrading torch (2.4.1+cu124 -> 2.4.1+cpu): Pending...
Multiple source configurations found for download.pytorch.org - pytorch-cpu, pytorch-cu124
Creating new session for download.pytorch.org
Multiple source configurations found for download.pytorch.org - pytorch-cpu, pytorch-cu124
[urllib3:urllib3.connectionpool] Starting new HTTPS connection (1): download.pytorch.org:443
[urllib3:urllib3.connectionpool] https://download.pytorch.org:443 "GET /whl/cpu/torch/ HTTP/1.1" 200 162168
Skipping wheel torch-2.4.1+cpu-cp310-cp310-win_amd64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp311-cp311-linux_x86_64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp311-cp311-win_amd64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp312-cp312-linux_x86_64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp312-cp312-win_amd64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp38-cp38-linux_x86_64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp38-cp38-win_amd64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp39-cp39-linux_x86_64.whl as this is not supported by the current environment
Skipping wheel torch-2.4.1+cpu-cp39-cp39-win_amd64.whl as this is not supported by the current environment
- Downgrading torch (2.4.1+cu124 -> 2.4.1+cpu): Installing...
- Downgrading torch (2.4.1+cu124 -> 2.4.1+cpu)
- Installing filelock (3.18.0): Pending...
- Installing filelock (3.18.0): Skipped for the following reason: Already installed
- Installing fsspec (2025.3.2): Pending...
- Installing fsspec (2025.3.2): Skipped for the following reason: Already installed
- Installing jinja2 (3.1.6): Pending...
- Installing jinja2 (3.1.6): Skipped for the following reason: Already installed
- Installing mpmath (1.3.0): Pending...
- Installing mpmath (1.3.0): Skipped for the following reason: Already installed
- Installing networkx (3.4.2): Pending...
- Installing networkx (3.4.2): Skipped for the following reason: Already installed
- Installing numpy (2.2.4): Pending...
- Installing numpy (2.2.4): Skipped for the following reason: Already installed
- Installing sympy (1.13.3): Pending...
- Installing sympy (1.13.3): Skipped for the following reason: Already installed
- Installing markupsafe (3.0.2): Pending...
- Installing markupsafe (3.0.2): Skipped for the following reason: Already installed
- Installing pillow (11.2.1): Pending...
- Installing pillow (11.2.1): Skipped for the following reason: Already installed
- Installing typing-extensions (4.13.2): Pending...
- Installing typing-extensions (4.13.2): Skipped for the following reason: Already installed
- Installing torchvision (0.19.1+cpu): Pending...
- Installing torchvision (0.19.1+cpu): Skipped for the following reason: Already installed

Start with the dependency specification documentation linked in the issue and reproduce the listed poetry install --extras "cpu" and cuda commands using the provided pyproject.toml. Compare the lock-file operations for torch and torchvision; done means the documented example selects and installs the matching CPU or CUDA variants consistently.