CPU package depends on non-CPU torch package

🐛 Bug

The torch-vision CPU wheel depends on the non-CPU torch wheel

Evidence: torchvision-0.6.0+cpu-cp36-cp36m-linux_x86_64.whl\torchvision-0.6.0+cpu.dist-info\METADATA:

Metadata-Version: 2.1
Name: torchvision
Version: 0.6.0+cpu
Summary: image and video datasets and models for torch deep learning
Home-page: https://github.com/pytorch/vision
Author: PyTorch Core Team
Author-email: [e-mail]
License: BSD
Platform: UNKNOWN
Requires-Dist: numpy
Requires-Dist: torch (==1.5.0)           <<<==== PROBLEM ====
Requires-Dist: pillow (>=4.1.1)
Provides-Extra: scipy
Requires-Dist: scipy ; extra == 'scipy'

To Reproduce

I’ve run into this with the poetry package manager for version 1.4.0 and 0.5.0, but the issue is also present in newer versions as can be seen in the previous snippet.

λ poetry lock -vvv                                                                         
Using virtualenv: C:\Users\korij_000\AppData\Local\pypoetry\Cache\virtualenvs\bla-8bWMJ8mE-
py3.6                                                                                      
Updating dependencies                                                                      
Resolving dependencies...                                                                  
   1: fact: bla is 0.1.0                                                                   
   1: derived: bla                                                                         
   1: fact: bla depends on torch (1.4.0+cpu)                                               
   1: fact: bla depends on torchvision (0.5.0+cpu)                                         
   1: selecting bla (0.1.0)                                                                
   1: derived: torchvision (0.5.0+cpu)                                                     
   1: derived: torch (1.4.0+cpu)                                                           
torch: 1 packages found for torchvision 0.5.0+cpu                                          
torch: 1 packages found for torch 1.4.0+cpu                                                
torch: Downloading wheel: torchvision-0.5.0%2Bcpu-cp27-cp27m-linux_x86_64.whl              
   1: fact: torchvision (0.5.0+cpu) depends on numpy (*)                                   
   1: fact: torchvision (0.5.0+cpu) depends on six (*)                                     
   1: fact: torchvision (0.5.0+cpu) depends on torch (1.4.0)                               
   1: fact: torchvision (0.5.0+cpu) depends on pillow (>=4.1.1)                            
   1: derived: pillow (>=4.1.1)                                                            
   1: conflict: torchvision (0.5.0+cpu) depends on torch (1.4.0)      <<<==== PROBLEM ====
   1: ! not torch (1.4.0) is satisfied by torch (1.4.0+cpu)                                
   1: ! which is caused by "bla depends on torch (1.4.0+cpu)"                              
   1: ! thus: torchvision is forbidden                                                     
   1: ! torchvision (0.5.0+cpu) is satisfied by torchvision (0.5.0+cpu)                    
   1: ! which is caused by "bla depends on torchvision (0.5.0+cpu)"                        
   1: ! thus: version solving failed                                                       
   1: Version solving took 1.964 seconds.                                                  
   1: Tried 1 solutions.                                                                   
                                                                                           
[SolverProblemError]                                                                       
Because torchvision (0.5.0+cpu) depends on torch (1.4.0)                                   
 and bla depends on torch (1.4.0+cpu), torchvision is forbidden.                           
So, because bla depends on torchvision (0.5.0+cpu), version solving failed.                

Note that I also had to work around another issue just to get poetry to find these packages since they are not on PyPI. See https://github.com/pytorch/pytorch/issues/39779

Expected behavior

I would expect the CPU wheel for torchvision to depend on the CPU version for torch.

[Korijn]

I’ve reached the conclusion that the problem lies with poetry’s dependency resolver which appears not to be fully compliant with PEP440. Check out https://github.com/python-poetry/poetry/issues/2543

[seemethere]

This may also be related to pytorch/pytorch#39779

Related yes but a separate problem. I opened pytorch/pytorch#39779 for that

oh haha,I guess I should’ve noticed that you also filed that originally!