Poetry: Exact inequality specifiers break sdist installation

[connorbrinton]

• [x] I am on the latest Poetry version.
• [x] I have searched the issues of this repo and believe that this is not a duplicate.
• [x] If an exception occurs when executing a command, I executed it again in debug mode (-vvv option).

• OS version and name: macOS Mojave 10.14.6
• Poetry version: 0.12.17
• Link of a Gist with the contents of your pyproject.toml file: https://gist.github.com/connorbrinton/c10dec54c67639099da1959fdb9942f9 (add empty src/example/__init__.py next to pyproject.toml for full repro)

Issue

Hi there! I'm having some trouble with the dependency specifiers generated for setup.py files when I use a version inequality in the pyproject.toml file. For example, I want to exclude torch = "!=1.1.0.post2" from being chosen as a concrete requirement, since it was never released on Linux (there's probably a better way to do this, but for discussion's sake 😅). Adding this to pyproject.toml, everything initially works fine:

❯ poetry update torch
Creating virtualenv example-py3.7 in /Users/.../project/.venv
Updating dependencies
Resolving dependencies... (1.8s)

Writing lock file


Package operations: 3 installs, 0 updates, 0 removals

  - Installing future (0.18.1)
  - Installing numpy (1.17.3)
  - Installing torch (1.3.0)

However, after I add code to the project, I get the following error:

❯ mkdir -p src/example
❯ touch src/example/__init__.py
❯ poetry -vvv install
Using virtualenv: /Users/.../project/.venv
Installing dependencies from lock file

Nothing to install or update

  - Skipping future (0.18.1) Already installed
  - Skipping numpy (1.17.3) Already installed
  - Skipping torch (1.3.0) Already installed
  - Installing example (0.1.0)

[EnvCommandError]                                                                                   
Command ['/Users/.../project/.venv/bin/python', '-m', 'pip', 'install', '-e', '                                           
/Users/.../project'] errored with the following return code 1, and output:       
Obtaining file:///Users/.../project                                              
Collecting torch<1.1.0.post2,>1.1.0.post2 (from example==0.1.0)                                                  
  Could not find a version that satisfies the requirement torch<1.1.0.post2,>1.1.0.post2 (from example==0.1.0)   
(from versions: 0.1.2, 0.1.2.post1, 0.1.2.post2, 0.4.1, 1.0.0, 1.0.1, 1.0.1.post2, 1.1.0, 1.1.0.post2, 1.2.0, 1  
.3.0)                                                                                                            
No matching distribution found for torch<1.1.0.post2,>1.1.0.post2 (from example==0.1.0)                          
You are using pip version 19.0.3, however version 19.3 is available.                                             
You should consider upgrading via the 'pip install --upgrade pip' command.                                       

Exception trace:
 /Users/connor/.poetry/lib/poetry/_vendor/py3.7/cleo/application.py in run() at line 94
   status_code = self.do_run(input_, output_)
 /Users/connor/.poetry/lib/poetry/console/application.py in do_run() at line 88
   return super(Application, self).do_run(i, o)
 /Users/connor/.poetry/lib/poetry/_vendor/py3.7/cleo/application.py in do_run() at line 197
   status_code = command.run(input_, output_)
 /Users/connor/.poetry/lib/poetry/console/commands/command.py in run() at line 77
   return super(BaseCommand, self).run(i, o)
 /Users/connor/.poetry/lib/poetry/_vendor/py3.7/cleo/commands/base_command.py in run() at line 146
   status_code = self.execute(input_, output_)
 /Users/connor/.poetry/lib/poetry/_vendor/py3.7/cleo/commands/command.py in execute() at line 107
   return self.handle()
 /Users/connor/.poetry/lib/poetry/console/commands/install.py in handle() at line 77
   builder.build()
 /Users/connor/.poetry/lib/poetry/masonry/builders/editable.py in build() at line 17
   return self._setup_build()
 /Users/connor/.poetry/lib/poetry/masonry/builders/editable.py in _setup_build() at line 42
   "python", "-m", "pip", "install", "-e", str(self._path)
 /Users/connor/.poetry/lib/poetry/utils/env.py in run() at line 539
   return super(VirtualEnv, self).run(bin, *args, **kwargs)
 /Users/connor/.poetry/lib/poetry/utils/env.py in run() at line 388
   raise EnvCommandError(e, input=input_)

install [--no-dev] [--dry-run] [-E|--extras EXTRAS] [--develop DEVELOP]

I verified that Dependency.to_pep_508() returns a good version string (I think):

In [1]: from poetry.packages.dependency import Dependency                                                          

In [2]: dep = Dependency('torch', '!=1.1.0.post2')                                                                 

In [3]: dep.to_pep_508()                                                                                           
Out[3]: 'torch (<1.1.0.post2,>1.1.0.post2)'

But it seems like along the path to setup.py, it gets turned into:

install_requires = \
[...
 'torch<1.1.0.post2,>1.1.0.post2',
 ...]

I think the issue has to do with this part of the SDist builder, which I think ends up removing the parentheses around the version specifier. I don't totally understand the pip/install_requires syntax though, so I could be totally off 😅

Any advice on how to get inequality specifiers to work would be greatly appreciated 😄

[charmasaur]

FWIW I'm having a somewhat similar issue with tensorflow = "^1.14,!=1.15.0", which may or may not be relevant. The difference is I'm using dephell to generate setup.py, which seems to go through correctly (I end up with 'tensorflow!=1.15.0,==1.*,>=1.14.0' in setup.py), but then somewhere during a subsequent pip install that specifier is getting translated to tensorflow>=1.14,<1.15.0,>1.15.0,<2, which obviously doesn't work.

[charmasaur]

OK, I think our issues are the same. Unless I'm missing something, in PEP440 there's no way to specify a union (disjunction) of version ranges -- according to PEP440, the comma always means "and" [1].

Assuming that's correct, the to_pep_508 of a !=x specifier should not be <x,>x, it should simply remain as !=x.

[1] https://www.python.org/dev/peps/pep-0440/#id53

[kleschenko]

I have a similar problem – poetry can not parse a version with inequality specifier trafaret>=0.9,<2.0,!=1.1.0 and fails to install a package with:

[SolverProblemError]                                                                                     
Because my-package (0.1.0) depends on both trafaret (<empty>) and trafaret (<empty>), my-package is forbidden. 

[connorbrinton]

Looks like this was just fixed nine hours ago and released in version 1.0.0b3! 🚀 I tested with the example I gave in my original post and was able to successfully install a package with an exact inequality requirement:

❯ poetry --version
Poetry version 1.0.0b3
❯ poetry install
Installing dependencies from lock file

Nothing to install or update

  - Installing example (0.1.0)
❯

I'm going to close this issue since my original problem has been resolved. @charmasaur @kleschenko Hopefully installing 1.0.0b3 solves your problems too! 🙂